Dissertations / Theses on the topic 'Eucalypt forest'
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Goodwin, Nicholas R. School of Biological Earth & Environmental Sciences UNSW. "Assessing understorey structural characteristics in eucalypt forests: an investigation of LiDAR techniques." Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2006. http://handle.unsw.edu.au/1959.4/28365.
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The potential of airborne LiDAR technology to quantify forest structure within eucalypt forests has been evaluated with a focus on the understorey stratum. To achieve this, three studies have been undertaken using multiple (4) LiDAR datasets acquired over three test areas located in Wedding Bells State Forest, Coffs Harbour, Australia. Initially, the effects of sensor configuration were evaluated using field measurements collected from three structurally and topographically differing field plots (40 x 90 m areas). Results indicated that canopy height profiles derived from LiDAR data at the plot scale were largely unaffected by a change in platform altitude from 1000 to 3000 m (p > 0.05). In addition, the derivation of individual tree attributes was found to be highly sensitive to the density of LiDAR observations whilst higher platform altitudes showed an increased proportion of single returns over forested areas. In the second study, an innovative field based approach was developed to sample the structure of the understorey (horizontally and vertically) for LiDAR validation purposes. Using two separate LiDAR datasets, this research confirmed that mean understorey height and understorey cover can be effectively mapped in areas of low to medium canopy cover whilst no significant relationship (p > 0.05) was identified between field and LiDAR estimates of maximum understorey height. In the third study, an optimised LiDAR beam interception model was developed and validated, and then applied to assess the interaction of extrinsic and intrinsic factors of the LiDAR survey. This demonstrated that the probability of beam interception through the forest canopy can be affected by factors both intrinsic (e.g. crown cover) and extrinsic (e.g. scan angle) to the structure of the canopy. Overall, the results of this research indicate that optimising the sensor configuration is important to the derivation of particular forest structural attributes and significantly, there is potential for LiDAR technology to provide quantitative and spatially detailed estimates of key understorey attributes such as mean height and cover.
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Henry, Joseph Douglas. "Evapotranspiration in a catchment dominated by eucalypt forest and woodland." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12283.
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There is on-going need for reliable estimates of evapotranspiration (ET) at catchment scales to support objective decision-making for managing water supplies, and enhancing understanding of processes and modelling. Without reliable estimates of ET, water supply and catchment management agencies are exposed to significant economic, social and even environmental risks. This thesis focuses on identifying possible methodologies for estimating ET in a catchment dominated by eucalypt forest and woodland. More specifically, this thesis tests the hypothesis that different methods of deriving daily, catchment ET for a headwater in Australia meet underlying assumptions and yield similar results. The hypothesis was tested by using three approaches to estimate catchment ET: soil moisture changes (point scale), satellite imagery of leaf area index (MODIS, hillslope scale), and discharge (streamflow) and the storage-discharge relationship (catchment scale). Data from Corin Catchment, an unregulated catchment vital to the Australian Capital Territory and the surrounding region, is the basis of this study. After the General Introduction (Chapter 1), methods for estimating ET in eucalypt communities throughout Australia at various temporal and spatial scales are systematically reviewed (Chapter 2). Of the 1614 original research papers investigated, 52 were included for further investigation. A clear outcome is that transpiration by the overstorey, measured using sap flow, is the most frequently measured component of ET, and that physiological studies dominate estimates of ET. Very few studies were conducted at the catchment scale. Further, scaling ET from tree to catchment scales was rarely attempted, and the effect of scaling for water resource management is mostly unquantified and requires attention. The first method used to calculate catchment ET is based on up-scaling of soil moisture changes on the basis of a digital soil map (Chapter 4). The data presented here rejects the hypothesis that ET (derived from soil moisture) and overstorey transpiration (derived from sap flow) are well correlated. Instead, the data suggest that soil moisture-derived ET and overstorey transpiration obtained water from different sources. The key findings of this chapter are that this approach is not suitable for estimating ET at catchment scales because it is restricted to drier periods, and because trees did not solely rely on the defined root-zone for water supply. The second method to calculate catchment scale ET (Chapter 5) tests if hillslope-scale satellite imagery (MODIS leaf area index) can be up-scaled to estimate catchment ET. An outcome of this work is that caution is needed when using MODIS leaf area index for water resource planning in evergreen forests across the globe, particularly for forests with significant understorey and a relatively open overstorey canopy at some periods of the year. This method is deemed not suitable for estimating ET over the study area. The third method to calculate catchment scale ET (Chapter 6) is based on integrating discharge using a single non-linear equation to characterise the study area. This method yielded catchment ET far greater (18 times larger) than the largest observed measure of potential ET. As with the method based on soil moisture changes, it was restricted to drier periods. This method was clearly unsuitable for estimating ET over the study area due to relatively quick recession, large range in hourly discharge and significant scattered recession at low discharge. Overall, this thesis rejects the hypothesis that different methods of deriving daily, catchment ET for a headwater in Australia meet underlying assumptions and yield similar results. An important limitation identified through this research is the ability to determine a ‘correct’ estimate of catchment ET. Further research should focus on enhancing understanding of scaling ET within and beyond Australia, generating more daily catchment ET from up-scaled soil moisture changes, further evaluating ET from up-scaled satellite imagery, and identifying catchment characteristics to allow ET to be derived from discharge. Water resource managers must be diligent when selecting and applying a method to estimate catchment ET.
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Sutherland, Elizabeth F. (Elizabeth Fyfe). "Fire, resource limitation and small mammal populations in coastal eucalypt forest." Thesis, School of Biological Sciences, 1999. http://hdl.handle.net/2123/5344.
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Phiri, Darius. "Biomass modelling of selected drought tolerant Eucalypt species in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85739.
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Thesis (MScFor)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The study aims at developing models for predicting aboveground biomass for selected drought tolerant Eucalyptus (E) species (E. cladocalyx, E. gomphocephala and E. grandis x camaldulensis) from the dry west coast. Biomass models were fit for each of the species and a cross-species model was parameterised based on pooled data for all the three species. Data was based on destructive sampling of 28 eucalypt trees which were 20 years of age and additional five five-year old E. gomphocephala trees. Preliminary measurements on diameter at breast height (dbh), height (h) and crown height were recorded in the field. The sampled trees were then felled and samples of discs, branches and foliage were collected. Density of the wood discs and the bark was determined by a water displacement method and computer tomography scanning (CT-scanner). Stem biomass was reconstructed using Smalian’s formula for volume determination and the calculated densities. Upscaling of the crown was carried out by regression equations formulated by employing the sampled branches. Further assessment was carried out on a sub-sample by subjecting the samples to different drying temperatures in a series between 60 and 105ºC. Linear models were parameterised by a simultaneous regression approach based on Seemingly Unrelated Regression (SUR) using the “Systemfit” R statistical package. The predictor variables employed in the study were dbh, d2h and h in which the coefficient of determination (R2), Mean Standard Error (MSE) and Root Mean Standard Error (RMSE) were used to determine the goodness of fit for the models. Akaike Information Criteria (AIC) was also used in the selection of the best fitting model. A system of equations consisting of five models was formulated for each Eucalyptus species. The biomass prediction models had degrees of determination (R2) ranging from 0.65 to 0.98 in which dbh and d2h were the main predictor variable while h improved the model fit. The total biomass models were the best fitting models in most cases while foliage biomass had the least good fit when compared to other models. When the samples were subjected to different drying temperatures, stem wood had the largest percentage change of 6% when drying from 60ºC to 105ºC while foliage had the lowest percentage change of less than 2%.
AFRIKAANSE OPSOMMING: Die doel met hierdie studie is om modelle vir die voorspelling van die bogrondse biomassa van drie droogte-bestande Eucalyptus (E) spesies (E. cladocalyx, E. gomphocephala en E. grandis x camaldulensis), gekweek op die droë kusvlakte in Wes-Kaapland, te ontwikkel. Biomassa modelle vir elk van die spesies is gepas en ’n model gegrond op die gekombineerde data van al drie die spesies, is geparameteriseer. Verder is die biomassa variasie onder verskeie droogingstemperature vasgestel. Die data versameling is uitgevoer gegrond op die destruktiewe mostering van 28 Eucalyptus bome wat 20 jaar oud was en ’n bykomende vyf vyfjarige E. gomphocephala bome. Die aanvanklike mates, naamlik deursnee op borshoogte (dbh), boomhoogte (h) en kroonhoogte is in die veld opgemeet. Die gemonsterde bome is afgesaag en monsters van stamhout skywe, takke en die bas is versamel. Die digtheid van die skywe en die bas is deur die waterverplasing metode, en Rekenaar Tomografie skandering (“CT-scanning”) vasgestel. Stam biomassa is rekonstrukteer deur gebruik te maak van Smalian se formule vir die vasstelling van volume en berekende digtheid. Die opskaal van die kroon biomassa is gedoen met behulp van regressie vergelykings van gekose takmonsters. Submonsters is onderwerp aan ’n reeks van verskillende drogingstemperature tussen 60 en 105ºC. Lineêre modelle is deur ’n gelyktydige regressie benadering gegrond op die Seemingly Unrelated Regression (SUR) wat ’n“Systemfit” R statistiese pakket gebruik, parameteriseer. Die voorspeller veranderlikes wat in hierdie studie gebruik is, is dbh, d2h en h waarin die koëffisient van bepaling (R2), gemiddelde standaardfout (MSE) en vierkantswortel van die gemiddelde standaardfout (RMSE) gebruik is om vas te stel hoe goed die model pas. Akaike Inligting Kriteria is gebruik vir die seleksie van die gepaste model. ’n Reeks vergelykings wat bestaan uit vyf modelle is vir elke Eucalyptus spesie geformuleer. Die biomassa voorspelling model het waardes vir die koëffisiente van bepaling (R2) opgelewer wat strek van 0.65 to 0.98% en waarin dbh en d2h die hoof voorspelling veranderlikes is, terwyl h die pas van die model verbeter. Die totale biomassa model het in die meeste gevalle die beste gepas en die blaarbiomassa die swakste as dit met die ander modelle vergelyk word. Tydens droging vind die grootste persentasie verandering van 6% by stamhout plaas tussen temperature van 60ºC tot 105ºC, en die kleinste persentasie verandering van minder as 2% by blare.
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Walden, Lewis L. "The effects of drought and wildfire on forest structure and carbon storage in a resprouting eucalypt forest." Thesis, Walden, Lewis L. ORCID: 0000-0001-9714-3603 (2020) The effects of drought and wildfire on forest structure and carbon storage in a resprouting eucalypt forest. PhD thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/54971/.
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The frequency and intensity of forest disturbances are projected to increase in many regions as climate changes, with an increased likelihood of multiple disturbance events occurring in short succession. The effects and importance of multiple disturbance events are gaining increasing attention but there is substantial uncertainty regarding the strength of interactions in relation to type, sequence, and relative timing. Forests play an integral role in climate change mitigation efforts, however, multiple disturbances could alter forest carbon dynamics, potentially reducing the storage capacity of impacted stands. Accurate accounting of carbon losses and transformations is thus imperative across forests globally, and particularly in non-conifer dominated types and with different responses such as resprouting.
This study investigated the effects of a global change-type drought (2010-11) and the Waroona Fire (2016), singularly on forest carbon dynamics in the regrowth Northern Jarrah (Eucalyptus marginata) Forest of southwestern Australia. This was followed by an investigation of the additive and interactive effects of these two disturbances on forest structure and recruitment. The affected forest stands were assessed using a plot-based forest inventory method combined with allometric equations and remote sensing metrics to determine carbon transformations and fire severity.
Following the drought die-off there was a significant loss of live standing carbon (49.3 t C ha-1), and a corresponding significant increase in the dead standing carbon pool six months after the drought. The Waroona Fire caused pyrogenic carbon emissions of between 10 and 21 t C ha-1, which corresponded to 5.5-12.2% of the mean pre-fire carbon storage, and the conversion of 59.2 – 72.8 t C ha-1 from the live to dead standing tree pool. This carbon, which comprises another 30-37% of the pre-fire carbon storage will be susceptible to loss over time both from decomposition and from future fires. Total immediate carbon emissions from the 360 km2 wildfire were estimated at 723,113 t C. When the disturbances were examined in combination there was no evidence of linked or compounding effects of these disturbances. Instead a strong effect of wildfire on live basal area (-20.7 ± 7.3 m2 ha-1) overwhelmed pre-existing drought impacts.
Eucalypt resprouting forests are particularly resilient, with focal species able to survive multiple stressors over a short time period. However, the newly regrowing burnt stands are vulnerable to future disturbance until they develop bark thick enough to withstand fire, and carbon stores to maintain resprouts following drought. The drought event preferentially removed large trees and the wildfire smaller trees from the live standing carbon pool. With a continually decreasing rainfall and projections of more frequent and severe fires in this area the trajectory of the regrowth in these stands is likely to be strongly tied to the future disturbance regime. Increases in disturbance frequency and intensity may therefore lessen the chances of these forests recovering to pre-fire structure and therefore carbon storage capacity.
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Turner, Russell Sean School of Biological Earth & Environmental Science UNSW. "An airborne Lidar canopy segmentation approach for estimating above-ground biomass in coastal eucalypt forests." Awarded by:University of New South Wales. School of Biological, Earth and Environmental Science, 2006. http://handle.unsw.edu.au/1959.4/27362.
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There is growing interest in airborne lidar for forest carbon accounting and precision forestry purposes. Airborne lidar systems offer a cost-effective, versatile, operationally flexible and robust sampling tool for forest managers. The objective of this study was to develop and test lidar canopy surface enhancement and segmentation processes for estimating dominant above-ground biomass (DAB) in a harvested eucalypt forest on the Central Coast of New South Wales (Australia). The Crown Infill, Trim and Smooth (CITS) process, incorporating a series of filters, algorithms, and selective multi-stage smoothing, was used to enhance lidar canopy surfaces prior to segmentation. Canopy segmentation was achieved using a vertical crown template approach termed the Spatially and Morphologically Isolated Crest (SMIC) process. SMIC delineates dominant tree crowns by detecting elevated crown crests within a 3D lidar canopy surface. Consolidated crown units constitute the basic sampling, analysis and reporting units for wall-to-wall forest inventory. The performance, sensitivity and limitations of these procedures were evaluated using a combination of simulated forest models and actual lidar forest data. Automated crown polygons were used as a sampling template to extract dominant tree height values which were converted to DAB estimates via height-to-biomass relationships derived from field survey and on-site destructive sampling. Results were compared with field based tree height and biomass estimates. Compared against a manually derived crown map from a 2ha field plot, canopy segmentation results revealed a producer???s accuracy of 76% and overall accuracy of 67%. Results indicated a trend toward greater crown splitting (fragmentation) as trees increase in age, height, stem diameter and crown size. Extracted dominant tree height values were highly correlated with ground survey height estimates (r2 0.95 for precision survey and r2 0.69 for standard survey). There was also no significant difference between SMIC and manual crown height estimates. SMIC units overestimated ground-based DAB by 5%; this increased to 36% with the inclusion of segmentation errors. However, SMIC estimation of total plot above-ground biomass (AGB) was within 9% of the ground-based estimate. Results are encouraging considering the mixed-species, multi-aged composition of the forest, and the combined effects of SMIC segmentation and lidar height errors.
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George, Amy Kathryn. "Eucalypt regeneration on the Lower Murray floodplain, South Australia." Connect to this title online, 2004. http://hdl.handle.net/2440/37706.
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Vegetation along the River Murray floodplains has been shown to be in a severe state of decline. This decline is amplified by the impositions of river regulation. In South Australia, where vegetation losses have been great, regeneration is limited and may result in not only individual tree losses but also widespread population decline. This study aimed to examine the relationship between river flows and the regeneration process in populations of Eucalyptus camaldulensis and Eucalyptus largiflorens. The current structure of the populations was examined to determine if a viable number of varying age-classed trees were present. Tree surveys conducted at Banrock Station determined that while densities were low for both species, E. camaldulensis had a more sustainable population structure than E. largiflorens. Growth stages for both species illustrated highly clumped distribution, which is believed to correspond with river flooding magnitudes and frequencies. To address the potential link between tree distribution and flooding within the River Murray, a hydrological analysis was conducted for Banrock Station using river flows at the South Australian border from 1900 to 2003. The amount of time growth stages for each species were inundated was found to be greatly reduced under regulated flows compared to natural flows. This has resulted in shifted localized regeneration patterns corresponding with E. camaldulensis' greater demand for inundation than E. largiflorens. Moderate magnitude flows have been most impacted by regulation, and consequently these are the very flows needed for floodplain tree population maintenance. Flowering and seed fall for E. camaldulensis and E. largiflorens were monitored at Banrock Station for 22 months to identify losses in reproductive potential resulting from tree decline. While seed viability was not affected by vigour, trees with visually reduced vigour were found to produce less fruit and had reduced seed fall, as well as a reduced rate of fruit development. Dendrochronological techniques were applied to floodplain trees. Age and size relationships could be established, implying that such techniques can be applied in South Australia to high quality sites. Growth responses within cohorts were similar and easily matched between individuals illustrating cyclic, but not necessarily seasonal correlations. This work verified the preferential selection of younger trees for dendroecological studies, and identified a relationship between on moderate flows and measurable girth expansion in both floodplain tree species.Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2004.
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Dore, David William Biological Earth & Environmental Sciences (BEES) UNSW. "Application of simple physiological growth models to coastal eucalypt regrowth forests in New South Wales." Awarded by:University of New South Wales. Biological, Earth and Environmental Sciences (BEES), 2006. http://handle.unsw.edu.au/1959.4/26200.
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This thesis explores issues relating to the application of physiological-process models (???process models???) of forest growth to mixed species, mixed age forests, in particular the coastal blackbutt forests of New South Wales. Using a dataset provided by State Forests of New South Wales (Carter 1994 unpubl.) a numeric description of the forest was developed and stand-level parameters of interest were derived, in particular the plot by plot stemwood volume growth from 1975 to 1999. The amounts of harvested volume, volume that died and volume that grew into the measurement population were identified separately, and several different means of accounting for volume change over time were investigated. A method for quantifying the impact of harvesting and other silvicultural practices on the growth of the forest was developed and programs were written to convert the stand-level summary of the harvest impact into a semi-random selection of trees that would be ???harvested??? from the database under the set of silvicultural assumptions (Dore et al. 1999). A number of process models were investigated and reviewed before selecting one particular model, SUSTAIN (Dewar 1997) for adaption to these forests. This model is a relatively simple process model with a small number of input parameters. The model was adapted so that it could be used to compare the SUSTAIN estimate of growth with the growth of an individual stand of trees in the Kendall Forest Management Area, between Wauchope and Taree on the mid-north coast of NSW. To improve the accuracy of the prediction of growth by SUSTAIN, a method of re-setting the state of the stand to the actual condition at the time of remeasurement was developed. In addition, the SUSTAIN model was extended to enable two separate levels of canopy to be described and grown separately. Ultimately the model was only partially successful in mirroring the growth predicted by the empirical data. Its partial success is attributed primarily to the difficulties associated with correctly determining the allocation parameters used by the model to assign net photosynthate to the roots, foliage and stemwood. The nature of the change in allocation parameters when the forest stand is disturbed by harvest or fire needs further investigation.
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Timo, Thiago Philipe de Camargo e. "Mamíferos de médio e grande porte em áreas de cultivo de eucalipto das bacias do Alto Paranapanema e Médio Tietê, Estado de São Paulo." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-17112009-081119/.
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A região compreendida entre os trechos alto do rio Paranapanema, médio do rio Tietê e o rio Sorocaba possui longo histórico de influência humana na paisagem. Esta influência intensificouse nos dois últimos séculos com a passagem de estradas de ferro e a construção de hidroelétricas, entre outras modificações que implicaram em alterações do uso da terra. Uma das mudanças significativas foi a chegada e expansão rápida da silvicultura de eucalipto. A estrutura desta vegetação cultivada e seu ciclo produtivo têm influência sobre as comunidades vegetais e animais nativas. Neste estudo foi avaliada a influência da conformação geométrica da paisagem e da idade de plantio de áreas de silvicultura de eucalipto sobre padrões de distribuição e abundância de mamíferos de médio e grande porte. Foi possível demonstrar que herbívoros são favorecidos por áreas extensas de vegetação nativa com geometria simples, enquanto onívoros se beneficiam da ausência de grandes predadores e da geometria convoluta da vegetação nativa em áreas onde a matriz de eucalipto domina a paisagem. Onde o eucalipto é a feição dominante da paisagem agrícola, estas espécies utilizam o interior dos talhões em fase intermediária de cultivo, quando existe sub-bosque que ofereça abrigo e recursos alimentares. Tais observações reforçam a importância da manutenção de Áreas de Preservação Permanente e de Reserva Legal em paisagens agrícolas, assim como questionam o conservadorismo na aplicação da legislação que leva ao embargo do corte de eucaliptais com sub-bosque, diminuindo o valor de conservação desta cultura sobre a fauna de médios e grandes mamíferos nativos. Palavras-chaves: mamíferos de médio e grande porte, padrões de distribuição e abundância, paisagem agrícola, eucalipto.The region comprehended amid the high portion of river Paranapanema, mid portion of river Tietê and the river Sorocaba, has a long history of human influence on landscape. This influence was intensified during the past two centuries through the passage of railroads and hydroelectric dam constructions along with other modifications that had implications on land use changes. One of the significant modifications was the arrival and rapid expansion of eucalypt silviculture. The structure and cycle of production of this cultivated vegetation have influence on plant and animal native communities. In this study, geometric conformity and age of planted stands in eucalypt silviculture areas were evaluated on patterns of distribution and abundance of medium to large size mammals. It was possible to demonstrate that herbivores are favored by extensive areas of native vegetation, while omnivores benefit from the absence of large predators and complex geometry of native vegetation in landscapes with dominant eucalypt matrix. Where eucalypt plantations are the commonest landscape features, these species use central areas of silviculture stands in intermediate stages of cultivation, when there is undergrowth that offers shelter and food resources. These observations reinforce the importance of Permanent Preservation Areas and Legal Reserves in agricultural landscapes, as well as they question the conservatism on application of environmental laws that leads to the legal impediment of harvest on eucalypt stands with undergrowth, decreasing conservation value of this culture for medium to large size mammals fauna.
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Smith, Amanda Jessica. "Campsite impact monitoring in the temperate eucalypt forests of Western Australia : an integrated approach /." Access via Murdoch University Digital Theses Project, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040504.151201.
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Thesis (Ph.D.)--Murdoch University, 2003.Thesis submitted to the Division of Science and Engineering. "Supported by CRC for Sustainable Tourism and Dept of Conservation and Land Management (Western Australia)". Bibliography: leaves 334-355.
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Ross, Karen School of Biological Earth & Environmental Sciences UNSW. "Effects of fragmentation and disturbance on a eucalypt open-forest plant community in south-eastern Australia." Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2005. http://handle.unsw.edu.au/1959.4/22454.
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This study documented effects of fragmentation and disturbance on a coastal eucalypt dry open-forest plant community at Port Stephens-Myall Lakes, south-eastern Australia. The study evaluated the relative influence of fragment size (range <1-75ha), fragment or edge age (< 1-25y), time since fire (5-25y) and anthropogenic disturbance (minor, major) on microclimate, native plant species richness and weed invasion. Plots were sampled for native and exotic species richness per 25 m2 and edge transects for light, soil moisture, soil temperature, vegetation structure, native species richness and exotic species richness and cover. Depths of edge influence (DEI) were all < 20m inside the forest edge. Younger edge zones were lighter, had hotter and drier soils and more native species than forest interiors. Older edge zones were shadier, had warmer and moister soils and fewer native species than forest interiors, due to vegetation thickening in the edge zone. Light and soil moisture followed linear or monotonic edge-to-interior gradients in younger edges, but more complex patterns in older edges. Soil-temperature DEI decreased with increasing edge age. Fragment size had little influence on edge effects, but those for light developed more rapidly in smaller fragments, and recent fire was associated with reduced richness in edge zones of smaller fragments. Both anthropogenic disturbance and fire enlarged DEI for native species richness. Major anthropogenic disturbance coupled with fragmentation produced a stronger and more immediate loss of native species than fragmentation alone. Small fragments with minor disturbance had fewer native species per 25 m2 than larger fragments, but only after >10y since fragmentation. Analysis of forest interior portions of transects revealed that edge effects, and possibly disturbance, were largely responsible for this loss of native species with time, rather than effects of area. Despite a viable soil seed bank in fragments and the surrounding matrix, weed invasion in fragments was minimal. Exotic species were concentrated in edge zones, and were promoted by major anthropogenic disturbance within fragments. Results were highly dependent on fragment or edge age, and external influences of fragmentation (edge effects and disturbance), were more important than biogeographic (area-driven) factors. Impacts of fragmentation were compounded when combined with disturbance.
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Botman, Ilse. "Production potential of Eucalypt woodlots for bioenergy in the Winelands region of the Western Cape." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4281.
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Thesis (MScFor (Forest and Wood Science))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: The purpose of the study was to investigate the potential tree taxa that could be grown as a source of biomass in the Cape Winelands region. The trials comprises of two different aspects. The first being the estimation of potential volume, density and biomass of a pair of six year-old stands of E. gomphocephala and E. cladocalyx families at two climatically different sites within the study region. The second part of the study was the early growth assessment of alternative taxa that could be planted in the region compared to the regional mainstay E. cladocalyx. The volume of families was estimated using appropriate volume equations and using the form height were none were available. The best volume yield varied from 4.6 to 11.2 m3 ha-1a-1, at the dry and sub-humid sites, respectively. Wood density, estimated from non-destructive samples at both sites, varied from 620 (sub-humid) to 588 kg m-3 (dry site). The estimated biomass production rate of the top producing families yielded 2.7 and 6.9 t ha -1a -1 at the dry and sub-humid sites, respectively. In terms of estimated biomass and survival, E. gomphocephala was more suited to the dry site, while E. cladocalyx displayed superior yield than E. gomphocephala on the sub-humid site, but not significantly so. Early growth assessment of the trial of alternative taxa found that the hybrid E. grandis × camldulensis and E. grandis × urophylla had superior biomass indices, but were more susceptible to infestation by Thaumastocoris peregrinus and Gonipterus scuttelatus.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om potensiële boom taksa vir gebruik as ’n bron van biomassa in die Kaapse Wynlandstreek te ondersoek. Die proewe behels twee aspekte: eerstens die beraming van die potensiële volume, digtheid en biomassa van sesjaaroue opstande met families van E. gomphocephala en E. cladocalyx by twee klimatologies verskillende groeiplekke in die studiegebied; tweedens die beoordeling van die vroeë groei van alternatiewe taksa wat in die streek geplant kan word in vergelyking met die streek se historiese staatmaker-spesie E. cladocalyx. Die volume van die families is beraam deur gebruik te maak van toepaslike volumevergelykings, en met behulp van ’n vormfaktor waar vergelykings nie beskikbaar was nie. Die volume aanwas by die droë en sub-humiede groeiplekke was onderskeidelik 4.6 en 11.2 m3 ha-1j-1. Houtdigtheid is beraam deur nie-destruktiewe monsters uit die opstand te neem. Gemiddelde digthede het variëer van 588 (sub-humied) tot 620 kg m-3 (droë groeiplek). Die beraamde biomassaproduksie van die top-families beloop onderskeidelik 2.7 en 6.9 t ha -1j -1 vir die droë en sub-humiede groeiplekke. In terme van beraamde biomassa en oorlewing, is E. gomphocephala meer geskik vir droër groeiplekke , terwyl E. cladocalyx by die sub-humiede groeiplek ’n hoër opbrengs as E. gomphocephala getoon het, hoewel nie betekenisvol nie. Beramings van die vroeë groei by die proef met alternatiewe taksa het getoon dat die basters E. grandis × camldulensis en E. grandis × urophylla hoër biomassa-indekse het, maar meer vatbaar is vir besmetting deur Thaumastocoris peregrinus en Gonipterus scuttelatus.
Centre for Renewable and Sustainable Energy Studies
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McElhinny, Chris, and chris mcelhinny@anu edu au. "Quantifying stand structural complexity in woodland and dry Sclerophyll Forest, South-Eastern Australia." The Australian National University. Centre for Resource and Environmental Studies, 2005. http://thesis.anu.edu.au./public/adt-ANU20060322.133914.
Full textAbstract:
In this thesis I present and test a methodology for developing a stand scale index of structural complexity. If properly designed such an index can act as a summary variable for a larger set of stand structural attributes, providing a means of ranking stands in terms of their structural complexity, and by association, their biodiversity and vegetation condition. This type of index can also facilitate the use of alternative policy instruments for biodiversity conservation, such as mitigation banking, auctions and offsets, that rely on a common currency the index value that can be compared or traded between sites. My intention was to establish a clear and documentable methodology for developing a stand scale index of structural complexity, and to test this methodology using data from real stands.¶
As a starting point, I reviewed the literature concerning forest and woodland structure and found there was no clear definition of stand structural complexity, or definitive suite of structural attributes for characterising it. To address this issue, I defined stand structural complexity as a combined measure of the number of different structural attributes present in a stand, and the relative abundance of each of these attributes. This was analogous to approaches that have quantified diversity in terms of the abundance and richness of elements. It was also concluded from the review, that stand structural complexity should be viewed as a relative, rather than absolute concept, because the potential levels of different structural attributes are bound within certain limits determined by the inherent characteristics of the site in question, and the biota of the particular community will have evolved to reflect this range of variation. This implied that vegetation communities with naturally simple structures should have the potential to achieve high scores on an index of structural complexity.¶
I proposed the following five-stage methodology for developing an index of stand structural complexity:
1. Establish a comprehensive suite of stand structural attributes as a starting point for developing the index, by reviewing studies in which there is an established relationship between elements of biodiversity and structural attributes.
2. Develop a measurement system for quantifying the different attributes included in the comprehensive suite.
3. Use this measurement system to collect data from a representative set of stands across the range of vegetation condition (highly modified to unmodified) and developmental stages (regrowth to oldgrowth) occurring in the vegetation communities in which the index is intended to operate.
4. Identify a core set of structural attributes from an analysis of these data.
5. Combine the core attributes in a simple additive index, in which attributes are scored relative to their observed levels in each vegetation community.¶
Stage one of this methodology was addressed by reviewing a representative sample of the literature concerning fauna habitat relationships in temperate Australian forests and woodlands. This review identified fifty-five studies in south-east and south-west Australia, in which the presence or abundance of different fauna were significantly (p<0.05) associated with vegetation structural attributes. The majority of these studies concerned bird, arboreal mammal, and ground mammal habitat requirements, with relatively fewer studies addressing the habitat requirements of reptiles, invertebrates, bats or amphibians. Thirty four key structural attributes were identified from these fifty-five studies, by grouping similar attributes, and then representing each group with a single generic attribute. This set, in combination with structural attributes identified in the earlier review, provided the basis for developing an operational set of stand level attributes for the collection of data from study sites.¶
To address stages two and three of the methodology, data were collected from one woodland community Yellow Box-Red Gum (E. melliodora-E. Blakelyi ) and two dry sclerophyll forest communities Broadleaved Peppermint-Brittle Gum (E. dives-E. mannifera ), Scribbly Gum-Red Stringybark (E. rossii E. macrorhyncha ) in a 15,000 km2 study area in the South eastern Highlands Bioregion of Australia. A representative set of 48 sites was established within this study area, by identifying 24 strata, on the basis of the three vegetation communities, two catchments, two levels of rainfall and two levels of condition, and then locating two sites (replicates) within each stratum. At each site, three plots were systematically established, to provide an unbiased estimate of stand level means for 75 different structural attributes.¶
I applied a three-stage analysis to identify a core set of attributes from these data. The first stage a preliminary analysis indicated that the 48 study sites represented a broad range of condition, and that the two dry sclerophyll communities could be treated as a single community, which was structurally distinct from the woodland community. In the second stage of the analysis, thirteen core attributes were dentified using the criteria that a core attribute should:¶
1. Be either, evenly or approximately normally distributed amongst study sites;
2. Distinguish between woodland and dry sclerophyll communities;
3. Function as a surrogate for other attributes;
4. Be efficient to measure in the field.
The core attributes were: Vegetation cover <0.5m Vegetation cover 0.5-6.0m; Perennial species richness; Lifeform richness; Stand basal area of live trees; Quadratic mean diameter of live stems; ln(number of regenerating stems per ha+1); ln(number of hollow bearing trees per ha+1);ln(number of dead trees per ha+1);sqrt(number of live stems per ha >40cm dbh); sqrt(total log length per ha); sqrt(total largelog length per ha); Litter dry weight per ha. This analysis also demonstrated that the thirteen core attributes could be modelled as continuous variables, and that these variables were indicative of the scale at which the different attributes operated.¶
In the third and final stage of the analysis, Principal Components Analysis was used to test for redundancy amongst the core attributes. Although this analysis highlighted six groupings, within which attributes were correlated to some degree, these relationships were not considered sufficiently robust to justify reducing the number of core attributes.¶
The thirteen core attributes were combined in a simple additive index, in which, each attribute accounted for 10 points in a total index value of 130. Attributes were rescaled as a score from 0-10, using equations that modelled attribute score as a function of the raw attribute data. This maintained a high correlation (r > 0.97, p< 0.0001) between attribute scores and the original attribute data. Sensitivity analysis indicated that the index was not sensitive to attribute weightings, and on this basis attributes carried equal weight. In this form my index was straightforward to apply, and approximately normally distributed amongst study sites.¶
I demonstrated the practical application of the index in a user-friendly spreadsheet, designed to allow landowners and managers to assess the condition of their vegetation, and to identify management options. This spreadsheet calculated an index score from field data, and then used this score to rank the site relative to a set of reference sites. This added a regional context to the operation of the index, and is a potentially useful tool for identifying sites of high conservation value, or for identifying sites where management actions have maintained vegetation quality. The spreadsheet also incorporated the option of calculating an index score using a subset of attributes, and provided a measure of the uncertainty associated with this score.¶
I compared the proposed index with five prominent indices used to quantify vegetation condition or habitat value in temperate Australian ecosystems. These were: Newsome and Catlings (1979) Habitat Complexity Score, Watson et al.s (2001) Habitat Complexity Score, the Site Condition Score component of the Habitat Hectares Index of Parkes et al. (2003), the Vegetation Condition Score component of the Biodiversity Benefits Index of Oliver and Parkes (2003), and the Vegetation Condition Score component of the BioMetric Assessment Tool of Gibbons et al. (2004). I found that my index differentiated between study sites better than each of these indices. However, resource and time constraints precluded the use of a new and independent data set for this testing, so that the superior performance of my index must be interpreted cautiously.¶
As a group, the five indices I tested contained attributes describing compositional diversity, coarse woody debris, regeneration, large trees and hollow trees these were attributes that I also identified as core ones. However, unlike these indices, I quantified weeds indirectly through their effect on indigenous plant diversity, I included the contribution of non-indigenous species to vegetation cover and did not apply a discount to this contribution, I limited the direct assessment of regeneration to long-lived overstorey species, I used stand basal area as a surrogate for canopy cover, I quantified litter in terms of biomass (dry weight) rather than cover, and I included the additional attributes of quadratic mean diameter and the number of dead trees.¶
I also concluded that Parkes et al. (2003), Oliver and Parkes (2003), and Gibbons et al. (2004), misapplied the concept of benchmarking, by characterising attributes in terms of a benchmark range or average level. This ignored processes that underpin variation at the stand level, such as the increased development of some attributes at particular successional stages, and the fact that attributes can respond differently to disturbance agents. It also produced indices that were not particularly sensitive to the differences in attribute levels occurring between stands. I suggested that a more appropriate application of benchmarking would be at the overarching level of stand structural complexity, using a metric such as the index developed in this thesis. These benchmarks could reflect observed levels of structural complexity in unmodified natural stands at different successional stages, or thresholds for structural complexity at which a wide range of biota are present, and would define useful goals for guiding on-ground management.
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Chagas, Thiago Xavier. "Biodegradação de tocos de Eucalyptus sp. pela ação de cupins xilófagos." Universidade Federal de Sergipe, 2016. https://ri.ufs.br/handle/riufs/3025.
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Eucalyptus plantations can be managed under the cutting regime and retirement or coppice. After harvest there is the remnants’ accumulation of hard degradation culture, including the stump. This forest residue can be a micro-habitat and abundant food source for termites. The identification of termites’ species that occur at stumps can be a viable alternative to accelerate the process of degradation, assisting in partial or total removal. The aim of the study was to identify species of termites in stumps of Eucalyptus urograndis and evaluate its biodegradation in areas with two and four years old after cutting. The study was conducted in two areas, with aftercut ages of two and four years, located in the city of Entre Rios, Bahia, Brazil. The stumps were fragmented, with the aid of a cutter, and termites collected and deposited in 15 ml Falcon tubes, containing 80% alcohol. The termites were identified by key taxonomic aid and comparisons among copies from the base collection of Forest Entomology Laboratory of the Federal University of Sergipe, and the Zoology Museum of the University of Sao Paulo. The measurement of the diameter and height of the stumps were performed before and after fragmentation. After this measurement, the initial volume and the final volume of the stumps were calculated, to determine their biodegradation. To evaluate stumps’ biodegradation in the aftercut ages, data were analyzed by SAS 9.0 software, using the ANOVA for comparison. Seven species of termites, which belongs to four genera in the Termitidae family, were collected. Nasutitermes corniger, N. kemneri and Amitermes amifer were dominants. In the stumps biodegradation analysis was verified a significant difference between the afetrcut ages of two and four years. It is possible to find termites in stumps of Eucalyptus urograndis foraging alone or associated with other species. They are able to biodegrade stumps of Eucalyptus urograndis areas aged two and four years after cutting. There is an increasing trend in biodegradation of the stumps in area with higher post-crop age, as observed in the area with four years of age.As plantações de eucalipto podem ser manejadas sob o sistema de alto fuste ou em talhadia, sendo que após a colheita há o acúmulo de restos da cultura de difícil degradação, incluindo o toco. Este resíduo florestal pode representar um micro-habitat e recurso alimentar abundante para cupins. A identificação das espécies de cupins que ocorrem em tocos pode ser uma alternativa viável para acelerar o seu processo de degradação, auxiliando na remoção parcial ou total dos tocos. O objetivo do estudo foi identificar espécies de cupins em tocos de Eucalyptus urograndis e avaliar a sua biodegradação em áreas com dois e quatro anos de idade após o corte do primeiro ciclo de plantação. O estudo foi conduzido em duas áreas, com idades de dois e quatro anos após o corte, localizadas no município de Entre Rios, Bahia, Brasil. Os tocos foram fragmentados, com auxílio de um facão, e os cupins coletados e depositados em tubos Falcon 15 ml, contendo álcool 80%. Os cupins foram identificados com auxílio de chave taxonômica e comparação com exemplares da coleção base do Laboratório de Entomologia Florestal, da Universidade Federal de Sergipe, e do Museu de Zoologia, da Universidade de São Paulo. A medição do diâmetro e altura dos tocos foi realizada, antes e após a sua fragmentação. Após esta medição, foi calculado o volume inicial e o volume final dos tocos. Para avaliar a biodegradação de tocos, os dados foram convertidos para porcentagem e analisados pelo programa SAS 9.0, usando para comparação a ANAVA. Foram coletadas sete espécies de cupins, pertencentes a quatro gêneros, da família Termitidae. Nasutitermes corniger, N. kemneri, e Amitermes amifer foram dominantes. Na análise de biodegradação dos tocos houve diferença significativa entre as idades de dois e quatro anos, sendo a biodegradação maior na área com quatro anos de idade após o corte. É possível encontrar espécies de cupins em tocos de Eucalyptus urograndis, sejam forrageando isoladamente ou associações com outras espécies, sendo elas capazes de biodegradar tocos de Eucalyptus urograndis nas áreas com idade de dois e quatro anos após o corte. Há uma tendência de aumento na biodegradação dos tocos em área com maior idade após o corte, como constatado na área com quatro anos de idade.
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Dovey, Steven Bryan. "Effects of clear felling and residue management on nutrient pools, productivity and sustainability in a clonal eucalypt stand in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71720.
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Thesis (PhD(For))--Stellenbosch University, 2012.The subtropical ecosystem of the Zululand coastal plain is prized by the South African commercial plantation forestry industry for its rapid clonal Eucalyptus growth, short rotations (6 to 7 years) and high yields. This region is typified by sandy soils that are low in clay and organic matter, have small nutrient reserves and are poorly buffered against nutrient loss. The subtropical climate induces rapid decomposition of residues and tree litter resulting in small litter nutrient pools and rapid nutrient release into the soil, particularly after clearfelling. A combination of large nutrient demands through rapid growth, rapid nutrient turnover and small soil nutrient reserves implies that sites in this region are sensitive and may be at risk of nutrient decline under intensive management. The work in this study set out to determine the risk of nutrient depletion through harvesting and residue management on a site within the Zululand region, to assess nutritional sustainability and the risk of yield decline in successive rotations. Some bulk biogeochemical cycling processes of macro-nutrients nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) were assessed, and assessments also included sodium (Na). An existing Eucalyptus stand was clearfelled and treatments were imposed on the residues after broadcasting to simulate various levels of nutrient loss through levels of harvesting intensity and residue management. These included residue burning (Burn), residue retention (No-Burn), fertilisation (stem wood nutrient replacement), whole tree harvesting and residue doubling. Outer blocks of the stand were not felled, but included as replicates of an undisturbed standing crop treatment. Biogeochemical nutrient cycling processes were assessed primarily in the standing crop, Burn and No-Burn treatments, in the assumption that these represented the furthest extremes of nutrient loss. Data collection commenced a year prior to clearfelling and continued to two years and six months after planting with key data collection over a 20.1 month period from clearfelling to canopy closure (one year after planting). Water related nutrient pools and fluxes were assessed as atmospheric deposition (bulk rainfall, throughfall and stemflow) and gravitational leaching to 1m soil depth. Drainage fluxes were predicted using the Hydrus model and real-time soil moisture data. Zero tension lysimeters collected soil solution for chemical analysis. Sequential coring in the 0 to 30cm soil layer was used to determine in situ soil N mineralisation. Soil chemical and physical properties were assessed over the first meter of soil at clearfelling and new crop canopy closure to determine soil nutrient pools sizes. Biomass nutrient fluxes were assessed from litterfall, residue and litter decomposition, and above ground accretion into the tree biomass. Leaching and N mineralisation were monitored in the No-Burn, Burn and standing crop treatments only. Atmospheric deposition, while variable, was shown to be responsible for large quantities of nutrients added to the Eucalyptus stand. Nitrogen and K additions were relatively high, but within ranges reported in previous studies. Rapid tree canopy expansion and subsequent soil water utilisation in the standing crop permitted little water to drain beyond 1m resulting in small leaching losses despite a sandy well drained soil. Further leaching beyond this depth was unlikely under the conditions during the study period. Mineralisation and immobilisation of N also remained low with net immobilisation occurring. The standing crop was shown to be a relatively stable system that, outside of extreme climatic events, had a relatively balanced or positive nutrient budget (i.e. nutrient inputs minus outputs). Large quantities of nutrients were removed with stem-wood-only harvesting in the No-Burn treatment leaving substantial amounts on the soil surface in the harvest residues. Whole tree removal increased losses of all nutrients resulting in the largest losses of P and base cations compared to all other treatments. This was mostly due to high nutrient concentrations in the removed bark. Loss of N in the Burn treatment exceeded whole tree N losses through combustion of N held in the harvest residues and litter layer. The majority of K leached from the residues prior to burning and a relatively small fraction of the base cations were lost from the partially decomposed residues during burning. Ash containing substantial amounts of Ca and relatively large amounts of N and Mg remained after burning. Surface soil Ca and Mg was significantly increased by the ash which moved into the soil with rainfall directly after burning. Rapid soil moisture recharge occurred within a few months after clearfelling, increasing leaching from the upper 50cm of soil. Clearfelling increased net N mineralisation rates, increasing mobile NO3-N ions in the soil surface layers. Nitrate concentration peaked and K concentration dipped in the upper soil layers of the Burn treatment directly after burning. Deep drainage and leaching (beyond 1m depth) over the 20.1 month period was, however, not significantly different between the Burn and No-Burn treatments. Rapid soil moisture depletion and nutrient uptake with new crop growth reduced leaching fluxes to levels similar to the standing crop by six months after planting. Taking the full rotation into account, clearfelling induced a short-lived spike in N and cation leaching compared with the low leaching losses in the undisturbed standing crop. Soil N mineralisation over the 20.1 month period in the burnt treatment was half that of the No-Burn treatment. Growth and nutrient accumulation was significantly higher in the fertilised treatment than in other treatments up to 2.5 years of age. Growth in the Burn treatment was greatest compared to other treatments during the first few months, but slowed thereafter. No significant growth differences were found between all other treatments from a year to 2.5 years after planting. Early growth was therefore apparently not limited by N supply despite large differences in N mineralisation between Burn and No-Burn. Foliar vector analysis indicated that fertilisation improved growth initially through increased foliar N and P at six months after planting followed by Mg and Ca at one year. The Burn treatment was not nutrient limited. These growth results contrasted with similar international research on sandy tropical sites where growth was reduced after residue removal and increased after residue doubling. The combined nutrients released from pools in the litter layer or ash and soil in addition to atmospheric inputs were sufficient to provide most nutrients required to maintain similar growth rates across all treatments. This demonstrated the importance of residue derived nutrients to early growth nutrient supply. Reduced N mineralisation through a lack of substrate may limit N supply later in the rotation where residue had been removed. Construction of a nutrient budget for the system revealed that high levels of atmospheric inputs have the potential to partially replenish a large proportion N, K, and Ca lost during clearfelling, provided losses are constrained to stemwood removal only. However, loss of Mg that occurred primarily through leaching may not be replaced under the low Mg inputs recorded in this study. Larger nutrient removals (i.e. stemwood plus other plant parts) placed a heavier reliance on the small soil nutrient pools at this site which can limit future productivity. More intense harvesting and residue management practices dramatically increased the risk of nutrient depletion. Losses of specific nutrients depended on a combination of clearfelling biomass removal, residue burning and subsequent leaching. Nitrogen losses due to harvesting and burning were more substantial than those due to leaching. Mg and K losses depended most strongly on the time after clearfelling before re-establishment of the new crop and rainfall patterns, while Ca and P losses depended directly on the amount of biomass removed. Depletion risk was the greatest for Mg and K through rapid leaching, even after stem wood only removal. Deep root uptake and deep drainage with associated cation loss needs to be investigated further to quantify ecosystem losses and recovery of cations displaced beyond 1m. Atmospheric deposition is one of major factors countering nutrient losses. However, atmospheric inputs may not be reliable as these may lessen in future through pollution control legislation and climate change. Changes in growth rate under poor nutrient management practices are small and difficult to detect relative to the large impacts of changing weather patterns (drought), wildfire and pest and disease. This makes it difficult to prove nutrient related growth decline. It may be possible that improvements in genetics, silvicultural technologies and atmospheric inputs may also be masking site decline (in general) and in part explain the lack of evidence of a growth reduction in the region. As the poorly buffered sandy soils on the Zululand Coast are at risk of nutrient depletion under the short rotation, high productivity stands, it may be necessary to stipulate more conservative harvesting and residue management practices. A more conservative stem-wood only harvesting regime is recommended, retaining all residues on site. Residue burning should be avoided if N losses become a concern. The length of the inter-rotation period must be kept short to reduce cation leaching losses. Site nutrient pools need to be monitored and cations may eventually need to be replenished through application of fertilisers or ash residues from pulp mills. Management practices therefore need to be chosen based on the specific high risk nutrients in order to maintain a sustainable nutrient supply to current and future plantation grown Eucalyptus.
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Martins, Ruben Jacques. "Efeito do espaçamento e arranjo do plantio do eucalipto na capacidade operacional e custo da colheita com colhedora florestal." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-11032009-142847/.
Full textAbstract:
A escolha do espaçamento de plantio tem como objetivo inicial proporcionar para cada árvore o espaço suficiente para se obter o crescimento máximo com melhor qualidade e menor custo. Do ponto de vista da colheita mecanizada, o aumento da densidade da floresta implica diretamente na redução do volume individual das árvores, ocasionando também uma redução da capacidade produtiva do harvester.O objetivo deste estudo foi avaliar o efeito de diferentes espaçamentos e arranjos do plantio de povoamentos de eucalipto sobre a capacidade e custo operacional da colheita com harvester. A coleta de dados de produtividade do harvester foi feita em condições reais de operação, em dois povoamentos de eucalipto com diferentes espaçamentos: 6,0; 7,5; 9,0; 12; e 18 m2 por árvore, além do uso de um simulador de colheita. Usando-se os valores das variáveis espaçamento (E), volume médio (VM), diâmetro à altura do peito (DAP) e altura (H) aplicou-se um teste de regressão stepwise e se fez uma correlação para medir a participação dessas variáveis na capacidade operacional. Os custos operacionais dos equipamentos foram determinados através de um método contábil proposto pela FAO. O volume médio (VM) por árvore explicou 88 % da capacidade operacional da colhedora florestal e o espaçamento (E) afetou 8,5 %, sendo que o maior espaçamento é a causa do maior volume individual. Conseqüentemente, o custo da operação de colheita de árvores com harvester foi menor naqueles tratamentos com maior espaçamento. Os tratamentos simulados podem ser utilizados como reais para este tipo de comparação, dado que os tratamentos usando o simulador seguem a mesma tendência que a colheita real, ou seja, a maior espaçamento, maior volume individual por árvore e por tanto maior capacidade operacional do harvester. A maior proporção de tempo médio do ciclo de colheita por árvore foi o tempo de traçamento em condições de trabalho real, sendo que no caso da simulação da colhedora o maior tempo do ciclo foi de descasque-desgalhe. O modelo empírico apresentado pode ser uma ferramenta válida para predição de capacidade operacional do harvester.Plantation spacing selection has the primary object of assigning each tree enough space in which maximum growth and best quality can be attained with a minimum cost. From the harvest standpoint, an increase in stand density directly implies a decrease of individual tree volume, reducing also harvester productive capacity. The objective of this research is to assess the effects of several initial spacing and arrangement in eucalypt plantations on production capacity and operational capacity and costs of forest harvester. Real operational data were collected from two eucalypt plantations at different initial spacing, viz. 6.0, 7.5, 9.0, 12 and 18 m2 per tree. Simulation data were obtained from forest harvester simulator. Using spacement (E), mean tree volume (MV), diameter at breast height (DBH) and height (H) values, a stepwise regression test procedure was run, and correlations computed in order to measure their participation in operational capacity. Operational costs were computed with accounting method proposed by FAO. Mean tree volume (MV) explained 88% of forest harvester operational capacity. Spacement (E) affected 8.5% of harvester operational capacity; wider spacements were related to higher individual tree volumes. Harvesting operation costs were lower in wider spaced treatments. Simulated treatments can be used as in field conditions. Treatments under simulated conditions and real conditions had the same results: the wider the spacement, more individual volume tree and higher harvester operational capacity. The higher time of the harvest cycle was the cross-cutting operation in real conditions and the debarked and delimbing in simulated conditions. The empirical model can be a valid tool to predict the harvester operational capacity
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Webb, Garry Anthony. "The effects of logging on populations of small ground-dwelling vertebrates in montane eucalypt forest in South-Eastern New South Wales." Thesis, Canberra, ACT : The Australian National University, 1991. http://hdl.handle.net/1885/140692.
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Silveira, Patrícia Batista da. "Mamiferos de médio e grande porte em florestas de Eucalyptus spp com diferentes densidades de sub-bosque no município de Itatinga, SP." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-07042006-154033/.
Full textAbstract:
Estudos de fauna em florestas homogêneas de plantio comercial são ainda incipientes no país. Essas áreas de reflorestamento apresentam poucos recursos necessários à vida silvestre, quando comparadas às florestas nativas. Entretanto, sub-bosques presentes nessas florestas homogêneas podem fornecer ofertas de alimento, abrigo, proteção, e o estabelecimento de um ambiente favorável à movimentação dos animais - otimizando assim o uso desses locais pela fauna silvestre. Este estudo foi realizado no Horto Florestal de Itatinga, uma área com predomínio de florestas de eucalipto (Eucalyptus spp), e com remanescentes de vegetação nativa (floresta estacional semidecidual, cerrado, cerradão e áreas ripárias), localizada no município de Itatinga, no estado de São Paulo. A fim de verificar se a presença e a densidade do sub-bosque nas florestas de eucaliptos influenciam no uso desses locais pelos mamíferos de médio e grande porte, foram comparados três tipos de ambientes de eucalipto: um talhão de eucalipto sem subbosque, um talhão de eucalipto com sub-bosque intermediário, e um talhão de eucalipto com subbosque denso. Em cada um desses ambientes foram colocadas 24 parcelas de areia (armadilhas de pegadas) com iscas alimentares (banana, bacon e sal), para a observação do número de pegadas dos animais nas mesmas. Foram verificados os números de registros, as freqüências de ocorrência e as abundâncias relativas das espécies de mamíferos em cada ambiente, durante 15 dias do inverno de 2004 (estação seca) e 15 dias do verão de 2005 (estação chuvosa). O número de registros foi maior no ambiente de eucalipto com sub-bosque denso, e a riqueza de espécies foi maior no eucalipto com sub-bosque intermediário. O teste do Qui-quadrado (χ2) mostrou diferença significativa no número de registros entre os três ambientes, e entre os períodos inverno e verão. Foram verificadas as categorias tróficas dos mamíferos levantados nesses locais, e observou-se que os animais encontrados foram, em sua maioria, animais de hábitos mais generalistas e pouco exigentes quanto ao habitat. Foram encontradas no total 10 espécies de mamíferos de médio e grande porte nesses ambientes de eucalipto. A curva do coletor não mostrou estabilização, indicando que ainda havia espécies a serem levantadas nesses três ambientes de eucaliptos. Foi também realizado um levantamento qualitativo dos mamíferos de médio e grande porte na área de estudo em geral. Para isso, foram observados registros diretos e indiretos da mastofauna, como visualização de animais, pegadas, fezes, pêlos, tocas e carcaças; foram efetuadas também entrevistas, e houve a instalação de uma câmera trap (armadilha fotográfica). Este levantamento geral ocorreu durante 75 dias (entre julho de 2004 e abril de 2005). Foram encontradas 27 espécies de mamíferos nesse levantamento, mas a curva do coletor aplicada a esses registros também não se estabilizou. A maioria dos animais levantados são de hábitos alimentares generalistas; entretanto, foram registrados pelo menos quatro espécies de carnívoros (mais exigentes quanto à qualidade do habitat). Foram acusadas as presenças de oito espécies de mamíferos ameaçados de extinção no Horto de Itatinga.Fauna studies in homogeneous forests for commercial plantation purposes are still incipient in the country. These reforestation areas present a few resources necessary to the maintenance of wild life, when compared to the native forests. However, understories present in these homogeneous forests can provide food, shelter, protection and the establishment of a favorable environment to animal movement thus, optimizing the use of these reforestation areas by the wild fauna. This study took place in the Horto Florestal de Itatinga, an area of mostly eucalypts forests (Eucalyptus ssp) and remaining fragments of native vegetation (semideciduous seasonal forests, savannah and riparian forests), located in Itatinga, state of São Paulo, Brazil. In order to verify if the presence and density of the understories in the eucalypt forests influence in the use of these locations by medium and large-sized mammals, three types of eucalypt environment were compared: a stand of eucalypt without understory, a stand of eucalypt with intermediate understory an a stand of eucalypt with dense understory. Each of these environments received 24 sand plots (tracking traps) containing alimentary baits (banana, bacon and salt), for the observation of the number of animal tracks in each one of them. Registry numbers, frequency of occurrence and the relative abundance of mammals species in each environment, throughout 15 winter days in 2004 (dry season) and 15 summer days in 2005 (wet season), were verified. In the eucalypt environment with dense understory record numbers were higher, and in the eucalypt environment with intermediate understory the richness of species was bigger. The chi-square test (χ2) showed significant difference in registry numbers among these three environments, as well as between winter and summer periods. Dietary categories of the mammals observed in these sites were verified, and most of the observed animals belonged to generalist species, and they were not so demanding concerning their habitat. Ten species of medium and large-sized mammals were found in these eucalypts environments all told. The collectors curve was not stabilized, indicating that there were still other species to be surveyed in these three environments with eucalypts. A qualitative survey of medium and large-sized mammals in the study area in general, was also carried out. For this purpose, direct and indirect records of the mammals, as well as the visualization of these animals, their tracks, feces, hairs, burrows and carcasses were observed. Local people were interviewed and one camera trapping installed. This survey took place throughout 75 days (between July, 2004 e April, 2005). Twenty-seven species of mammals were found in this survey, but the collectors curve was not stabilized too. Most of the animals observed in this study belonged to generalist species; but at least four species of carnivores (animals are more demanding concerning their habitat) were recorded. This study also accused the presence of eight endangered species in the Horto de Itatinga.
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Almeida, Julio Cesar Raposo de. "Nutrição, crescimento, eficiência de uso de água e de nutrientes em povoamentos de Eucalyptus grandis fertilizados com potássio e sódio." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-09092009-110849/.
Full textAbstract:
Para avaliar os efeitos da fertilização potássica e sódica sobre a resposta do Eucalyptus grandis em crescimento, estado nutricional, eficiência de uso de água e de nutrientes foi instalado na Estação Experimental de Ciências Florestais de Itatinga (SP) em LVA distrófico (200 g kg-1 de argila) um experimento em blocos ao acaso contendo sete tratamentos: Testemunha, K1,5, K3,0, K4,5, KS3,0, Na3,0 e K1,5+Na1,5 (os valores correspondem à quantidade de K ou Na fornecidos em kmol ha-1, sob as formas de KCl, K2SO4 e NaCl). O nível crítico de K foliar variou de 6,6 a 5,0 g kg-1 e as amostragens realizadas no final da estação de chuvas (maio) sempre proporcionaram melhor avaliação do estado nutricional. A fertilização potássica elevou a resistência e/ou tolerância à ferrugem (Puccini pisidii Winter.). A concentração de Na na idade de 6 meses foliar atingiu 3,4 e 2,3 g kg-1 nos tratamentos Na3,0 e K1,5+Na1,5, mas o crescimento das árvores as concentrações reduziram para valores < 1,0 g kg-1, 36 meses pós-plantio. O Eucalyptus grandis foi capaz de absorver o Na e o transportar até as folhas, mantendo a relação K/Na >1 (elevada), uma característica relacionada às plantas tolerantes ao Na e à salinidade. A resposta do Eucalyptus grandis à fertilização potássica e sódica foi expressiva, enquanto a Testemunha alcançou 8,6 cm de DAP, 13,4 m de altura e 68 m3 ha-1 de madeira, 36 meses pós-plantio, sob a maior dose de potássio (K4,5), o DAP foi de 11,6 cm, a altura de 17,5 m que resultaram em 141 m3 ha-1 de madeira. A fertilização sódica, por sua vez, proporcionou árvores 13% (10,0 cm) mais grossas, 18% (15,7 m) mais altas, e produtividade de madeira 52% (103 m3 ha-1) maior que a Testemunha aos 36 meses pós-plantio. A combinação de K1.5+Na1.5, comparada ao fornecimento de K1,5, aumentou em 12% o volume de madeira. A produção de biomassa do tronco aos 36 meses pós-plantio nos tratamentos K3,0, Na3,0 e Testemunha foi de 55,1, 41,5 e 26,1 Mg ha-1, respectivamente. Os aumentos de produtividade estiveram diretamente relacionado com índices de área foliar (IAF) maiores aos 36 meses pós-plantio: K3,0 (5,4 m2 m-2), Na3,0 (3,2 m2 m-2) e Testemunha (2,7 m2 m-2). O conteúdo de K na parte aérea aos 36 meses pós-plantio foi de 82, 38 e 31 kg ha-1, respectivamente nos tratamentos K3,0, Na3,0 e Testemunha, e os tratamentos Na3,0 e Testemunha não diferiram significativamente. O conteúdo de Na no tratamento Na3,0 (51 kg ha-1) foi maior que nos tratamentos K3,0 e Testemunha (17 e 28kg ha-1). Desses totais, o lenho acumulou cerca de 40% do conteúdo de K e mais de 75% do conteúdo Na. O retorno de K ao 10 solo como folhedo no tratamento K3,0 foi de 14,9, 22,2 e 13,1 kg ha-1 ano-1, consecutivamente nos três anos de avaliação. Nos tratamentos Testemunha e Na3,0, as quantidades de K não ultrapassaram 8,8, 14,3 e 11,9 kg ha-1 ano-1. A ciclagem bioquímica do K foi bastante intensa (>80%) ao contrário do Na em que a retranslocação é menor (27%). A EUK estimada sob fertilização sódica (1356 kg MS kg-1) foi superior às dos tratamentos K3,0 (829 kg MS kg-1) e Testemunha (1042 kg MS kg-1) Os índices de recuperação de K e Na atingiram, respectivamente 44 e 52%, aos 36 meses pós-plantio. Sob fertilização potássica e sódica, a transpiração foi em média 20% maior que na Testemunha (P<0,06) foram respectivamente, 505, 519 e 397 mm. Nestas condições, estima-se que a transpiração diária do Eucalyptus grandis tenha variado de 2,6 a 3,6 mm dia-1. A importância do K para o controle do processo da transpiração pode ser comprovada através do índice de transpiração por unidade de área foliar que foi menor no tratamento K3,0 (0,62 mm dia-1 m-2) que na Testemunha (0,96 mm dia-1 m-2) e em Na3,0 (1,05 mm dia-1 m-2), função que aparentemente o Na não exerceu. Embora a fertilização tenha aumentado o consumo de água, essa prática estimulou o desenvolvimento do Eucalyptus grandis fazendo com que aumentasse a eficiência de uso de água (EUA) e diminuísse a exigência de água (EA). Em termos de biomassa, as estimativas da EUAB, em ordem crescente, foram de 0,0021, 0,0033 e 0,0041 kg L-1, o equivalente à exigência de 500, 304 e 248 L de água por kg-1 de tronco, respectivamente pela Testemunha, K3,3 e Na3,0. Ao considerar a produtividade em volume de madeira, os índice de EUAV estimados para os tratamentos K3,0 (0,0068 dm3 L-1) e Na3,0 (0,0057 dm3 L-1) foram maiores que o da Testemunha (0,0034, dm3 L-1), permitindo reduzir a exigência de água em mais de 100 L dm-3. Nesse contexto, a fertilização potássica é uma prática de manejo essencial que pode elevar a produtividade e aumentar a eficiência no uso de água em plantações de Eucalyptus grandis. A fertilização sódica, além de contribuir para o aumento da produtividade pode ser uma estratégia para elevar a eficiência de uso de potássio.The effects of potassium and sodium fertilizer applications on Eucalyptus grandis tree growth, nutritional status, water use efficiency and nutrients use efficiency were studied at the Itatinga Experimental Station (SP) on a Ferralsol (LVA dystrophic, 200 g kg-1 clay). Seven treatments were established in complete randomized block designs: Control, K1.5, K3.0, K4.5, KS3.0, Na3.0 and K1.5+Na1.5 (the values correspond to rates of Na or K applied as KCl, K2SO4 or NaCl, expressed in kmol ha-1). The critical level of K in leaves ranged from 6.6 g to 5.0 kg-1 and the sampling performed at the end of the rainy season (May) always provided better assessment of nutritional status. The potassium fertilization increased the resistance and / or tolerance to rust (Puccinia pisidii Winter.). The foliar Na concentration was 3.4 and 2.3 g kg-1 in Na3.0 and K1.5+Na1.5 treatments, respectively, six months after planting, but Na concentrations decreased with tree ageing down to 1,0 g kg-1 at age 36 months. Sodium was taken up by Eucalyptus grandis trees and carried up to leaves, keeping the ratio K / Na > 1. This ratio is characteristic of salinity tolerant plant. The response of Eucalyptus grandis trees to K and Na fertilizer applications was significant. While trees in the control treatment reached on average 8.6 cm in DBH, 13.4 m in height and 68 m3 ha-1 of stemwood at age 36 months, under the higher dose of K addition (K4.5), mean values of DBH, height, and stemwood volume were 11.6 cm, 17.5 m, and 141 m3 ha-1 in the K4.5 treatment. Sodium fertilizer application increased tree DBH by 13% (10.0 cm on average at age 36 months), height by 18% (15.7 m on average), and stemwood volume by 52% (103 m3 ha-1) compared to the Control treatment. Stemwood volume in the K1,5+Na1,5 treatment was 12% higher than in the K1,5 treatment. Trunk biomass at age 36 months in treatments K3,0, Na3,0 and Control were 55.1, 41.5 and 26.1 Mg ha-1, respectively. Leaf area index (LAI) at age 36 months were 5.4, 3.2 and 2.7 m2 m-2, in the K3,0, Na3,0 and Control treatments, respectively. The amount of K in the aboveground biomass at age 36 months was 82, 38 and 31 kg ha-1 in treatments K3.0, Na3.0 and Control, respectively, and was not significantly different in the Na3.0 and Control treatments. The Na content at age 36 months was significantly higher in the Na3.0 treatment (51 kg ha-1) than in the control and K3.0 treatments (17 e 28 kg ha-1). About 40% of the total amount of K aboveground and more than 75% of the amount of Na were found in 12 stemwood. The amount of K in litterfall was 14.9, 22.2 and 13.1 kg ha-1 yr-1 in K3.0, the first, second and third years after planting, respectively. In the other treatments, K content in litterfall over the same period was < 14.3 kg ha-1 yr-1. Retranslocations of K during leaf senescence were intense (> 80%) and Na retranslocations were much lower (27% on average). Potassium use efficiency, calculated as the ratio between biomass and K content aboveground at age 36 months, was greater in the Na3.0 treatment (1356 kg kg-1) than in treatments K3.0 (829 kg kg-1) and Control (1042 kg kg-1). The rates of K and Na recovery in aboveground tree components were 44 and 52%, respectively, 36 months after planting. Potassium and sodium fertilizers applications increased stand transpiration (P <0.06) by 20% relatively to the Control treatment, from 30 to 35 months after planting (505, 519 and 397 mm, respectively). The mean daily stand transpiration over the study period ranged from 2.6 mm day-1 in the Control treatment to 3.6 mm day-1 in the K3.0 treatment. The transpiration/LAI ratio was lower in the K3,0 treatment (0.62 mm day-1 m-2) than in the Control (0, 96 mm day-1 m-2) and Na3.0 (1.05 mm day-1 m-2) treatments. This pattern showed that K availability largely influenced tree transpiration control, and Na availability was unlikely to reduce the loss of water per unit of LAI. Potassium and sodium fertilizers applications increased both the growth and the transpiration of Eucalyptus grandis trees and led to an improvement in water use efficiency (WUE) in biomass (B) or wood volume (V). WUEB were 0.0021, 0.0033 and 0.0041 kg L-1 over the study period in treatments Control, K3.0, Na3.0, respectively. WUEV were higher in treatments K3.0 (0.0068 dm3 L-1) and Na3.0 (0.0057 dm3 L-1) than in the Control treatment (0.0034 dm3 L-1). Therefore, K fertilization increased stand productivity and WUE in fast growing Eucalyptus grandis plantations. Sodium fertilization, in addition to K fertilization, also increased productivity and might be a valuable option to increase potassium use efficiency in commercial Eucalyptus plantations.
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Silva, Renato Meulman Leite da. "Resposta à fertilização de plantios comerciais de Eucalyptus e sua correlação com as características edafoclimáticas e silviculturais em diferentes regiões do estado de São Paulo." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-22032012-085139/.
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Os nutrientes são recursos naturais indispensáveis para a produção de madeira, assim o manejo nutricional é essencial para a produtividade sustentável de madeira em florestas plantadas, as quais formam um setor importante na economia nacional, principalmente com as plantações de Eucalyptus, comuns no estado de São Paulo. Essas plantações ocupam extensas áreas, abrangendo sítios com diferentes características edafoclimáticas e podem ter sua produtividade limitada por deficiências nutricionais, causadas por baixa fertilidade dos solos onde são cultivadas e um manejo de fertilizações inadequado. Esse estudo visou identificar a limitação nutricional, avaliar o efeito de características edafoclimáticas e silviculturais na resposta à fertilização e determinar a produtividade atingível em plantações comerciais de Eucalyptus distribuídas por diferentes regiões do estado de São Paulo, representando um total de 52.700 ha. Para isso utilizou-se o delineamento de Parcelas Gêmeas (PGs) que consistiu na instalação de 161 parcelas que receberam adubações extras, em diversos plantios com 2 a 4 anos de idade, de matérias genéticos seminais ou clonais e em primeira rotação ou brotação. Essas parcelas foram pareadas e comparadas durante 2,5 anos com outras que receberam o manejo tradicional da floresta e através de estimativas de crescimento foi determinado à resposta à fertilização (RF) dos diferentes blocos experimentais. O estudo mostrou uma produtividade atingível de 49 m³.ha-1.ano-1 (22 Mg.ha-1.ano-1), sendo 11% superior a atual e com capacidade para chegar a 62 m³.ha-1.ano-1 (28 Mg.ha-1.ano-1) na região ao sul do estado, a mais produtiva. A RF média foi de 11,8 m³.ha-1.ano-1 (5,3 Mg.ha-1.ano-1). Além do incremento na produtividade, o tratamento com adubação potencial aumentou o índice de área Foliar (IAF) e a eficiência de uso da luz. A região sul também foi a mais responsiva ao manejo de fertilização, que teve boa correlação com os fatores climáticos (precipitação e déficit hídrico). O teor de matéria orgânica, argila, areia e a soma de bases (SB) também apresentaram correlação com a RF para a população estudada. Além da diferença entre as regiões, a RF foi diferente para o tipo de solo, textura e materiais genéticos. A análise de cada região apresentou boa correlação entre a RF e a granulometria do solo, SB e os teores de Magnésio (Mg), Potássio (K) e Fósforo (P).The nutrients are essentials resources to wood production, therefore a nutritional management is needful to maintain a sustainable productivity on forests plantations, which contribute as a important sector in the Brazilian economy, mainly due to Eucalyptus plantations, common in São Paulo state. These plantations cover extensive landscapes, over different sites, climate and soil conditions and the productivity can be limited by low soils fertility or a inappropriate fertilization management. This study aimed to identify nutritional limitation, evaluate the effect of the soil, climate and silviculture characteristics on fertilization response and determine the attainable productivity in Eucalyptus plantations widespread around 52,700 ha in different regions in São Paulo state. The Twin Plot design was used in 161 plots which receive additional fertilizations. These plots account stands of 2 to 4 years old, seedling or clonal plantations and establishment or coppice forests. The plots were paired and compared for 2.5 years with others which receive the usual fertilization management and through growth estimates to determine the fertilization response (FR) to each block (pair of plots). The results showed an attainable productivity of 49 m³.ha-1.yr-1 (22 Mg.ha-1.yr-1), 11% greater than the actual and also showed a capacity to reach 62 m³.ha-1.yr-1 (28 Mg.ha-1.yr-1), at the south of state, more productivity local. The average FR was 11,8 m³.ha-1.yr-1 (5,3 Mg.ha- 1.yr-1). Beyond the increment on wood productivity, the treatment with extra fertilizations also increased the leaf area index (LAI) and the light use efficiency. The south region also was the most responsive to the fertilizations management, which was a good correlation with the climate data (rainfall and water deficit). The contents of organic matter, clay, sand and sum of bases was the soil characteristics more correlated to the FR, at the studied forest. Beyond the difference between the regions, FR was different for soil type, texture, and genetic materials. The each local analysis presented good correlations between FR and some soil characteristics: sand, silt, clay, sum of bases, Magnesium (Mg), Potassium (K) and Phosphorous (P) contents.
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Pippen, Brendan Gerard Physical Environmental & Mathematical Sciences Australian Defence Force Academy UNSW. "Fuel moisture and fuel dynamics in woodland and heathland vegetation of the Sydney Basin." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Physical, Environmental and Mathematical Sciences, 2008. http://handle.unsw.edu.au/1959.4/38697.
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The vegetation of the Sydney Basin, Australia, is highly flammable and subject to a wide range of fire regimes. Sclerophyllous shrubs and sedges are common and in some vegetation types up to 70 % of fuel consumed during a fire can be live. Research into fire behaviour and fuel dynamics has been minimal. To address this issue this thesis investigated the principal factor affecting the ease of ignition and rate of combustion of individual fuel particles and fuel beds in bushfires: dead fine fuel moisture (FFM). Two common Sydney Basin vegetation types, eucalypt woodland and heathland, each with a history of problematic fire management, were measured in the field for diurnal fluctuations in FFM following rain, under conditions similar to when prescribed burns are conducted. The FFM components of current operational fire behaviour models were found to be inadequate for predictions of FFM and fire behaviour under these conditions. The equilibrium moisture content (EMC) of five fuel types from the field site was investigated in a laboratory study. An existing function describing EMC as a function of temperature and relative humidity was evaluated and found to be very accurate for these fuels. Two FFM predictive models incorporating this function were evaluated on the field data and the laboratory results were shown to be applicable to the estimation of FFM in the field. One model gave very accurate predictions of FFM below fibre saturation point, but its accuracy was reduced when screen level conditions were used instead of those measured at fuel level. A recent process-based model that accounts for rainfall showed promise for predicting when fuel is < 25 % FFM. Systematic problems with the radiation budget of this model reduced the accuracy of predictions and further refinement is required. Live fine fuel moisture content (LFMC) of common heathland shrubs and sedge was investigated over two years and found to be both seasonal and influenced by phenology. LFMC minima occurred in late winter and spring (August to October), and maxima were in summer (December to February) when new growth was recorded. The dominant near-surface fuel in mature heath was sedge. It was found to have little seasonal variation in its??? percentage dead but the percentage dead maxima occured at the same time as the LFMC minima of shrubs and sedge in both years. Simple instantaneous models for duff moisture content in woodland and heathland and LFMC and the percentage dead sedge in heathland were developed. The information gained by this study will form the basis for future development of fuel moisture models for prescribed burning guidelines and fire spread models specific to the vegetation communities of the Sydney Basin.
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Estrela, Sílvia Regina Marques Faria. "Wildfire effects on forest soil organic matter stocks and losses by runoff." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/19151.
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Doutoramento em Ciências e Engenharia do AmbienteO solo é considerado o maior reservatório de carbono (C) global e, um importante sumidouro de CO2 atmosférico. Os incêndios florestais são um fenómeno frequente nos ecossistemas mediterrânicos, em especial em Portugal. Nas últimas décadas verificou-se um aumento do número de incêndios e os cenários de alterações climáticas sugerem que os regimes de incêndios se poderão intensificar no futuro. Os incêndios florestais podem provocar efeitos importantes a curto e médio prazo em fatores chave da qualidade do solo, tais como a quantidade e qualidade da matéria orgânica (SOM). Devido à grande quantidade de carbono (C) armazenado no solo, mesmo pequenas mudanças na SOM poderão ter um efeito significativo sobre os ciclos biogeoquímicos e, consequentemente, sobre o clima global. Embora existam vários estudos que documentam os efeitos pós-fogo sobre os processos hidrológicos e de erosão, em termos de impactos sobre a quantidade (em termos de stocks e perdas de carbono orgânico (OC) por escorrência superficial), qualidade da SOM e sedimentos exportados, bem como a sua recuperação pós-fogo tem sido pouco estudados. Estes foram os principais objetivos deste estudo, realizado em plantações de eucalipto (Eucalyptus globulus), um dos tipos de vegetação florestal mais suscetíveis ao fogo no centro-norte de Portugal. O efeito dos incêndios florestais na qualidade da SOM do solo foi avaliado na camada superficial do solo (0-2 cm) em 4 períodos de amostragem, imediatamente antes das primeiras chuvas até dois anos após o incêndio. Para tal, foram utilizadas várias técnicas analíticas, tais como a deteção e caraterização de biomarcadores lipídicos por cromatografia gasosa/espetrometria de massa (GC-MS), caraterização de SOM por pirólise acoplada à cromatografia gasosa e à espetrometria de massa (Py-GC/MS) e, por ressonância magnética nuclear 13C de estado sólido (13C NMR). As exportações pós-fogo de OC por escorrência superficial e as respetivas contribuições das frações de carbono orgânico dissolvido (DOC), carbono orgânico particulado (POC) e carbono inorgânico dissolvido (DIC) foram também determinados em amostras de escorrência superficial recolhidas em intervalos de 1 a 2 semanas ao longo do primeiro ano após o incêndio. Os resultados mostraram que o incêndio provocou mudanças consideráveis na quantidade e qualidade da SOM. Estas incluíram a degradação térmica e quebra de compostos de n-alquilo. Aumentaram os rácios das cadeias curto-longo de n-alcanos e das cadeias de n- FAMEs, assim como a alteração dos respetivos índices. Além disso, a abundância relativa de certos biomarcadores específicos de determinadas plantas foram modificados, especialmente diminuição de terpenóides, tais como epiglobulol, ledol e globulol que são característicos do Eucalyptus globulus. Outras diferenças observadas no solo queimado foram a presença de levoglucosano, um marcador típico para a alteração térmica de polissacarídeos, maior abundância relativa de compostos derivados da lenhina (vanilina e metoxifenol) e a presença de estruturas de N-heteroaromáticos. Os espetros de 13C NMR também indicaram que o fogo produziu um aumento considerável na aromaticidade e condensação aromática da SOM. Estas diferenças verificaram-se durante o período de estudo, sugerindo uma lenta recuperação das propriedades do solo, possivelmente influenciadas, quer por uma recuperação limitada da vegetação, quer pela intensificação das perda de solo após o incêndio. O presente trabalho abordou também um tema pouco estudado como são os efeitos pós-fogo nas perdas de OC no solo por escorrência superficial. Os principais resultados apontaram para (i) uma maior quantidades de cinzas na encosta orientada a norte do que na encosta orientada a sul, enquanto que para a quantidade total de carbono orgânico (TOC) nas cinzas, estas não apresentaram diferenças; (ii) quer a perda total de sedimentos, quer a quantidade TOC do solo apresentouse maior na encosta orientada a norte do que a sul; (iii) a fração de OC que apresentou as maiores perdas, para ambas as encostas, foi a particulada. A quantificação das perdas de OC pós-fogo podem contribuir de forma relevante para a proteção dos ecossistemas, nomeadamente em termos da fertilidade do solo.
Soil is considered the largest carbon reservoir and an important global sink for atmospheric CO2. Wildfires are frequent in Mediterranean ecosystems, especially in Portugal. In recent decades there has been an increase in the number of fires and climate change scenarios suggest that the fire regimes are likely to increase in the future. Forest fires can have important short−to long−term implications for key aspects of soil quality, such as the quantity and quality of soil organic matter (SOM). Due to high amount of carbon (C) stored in soil, even slight alterations of SOM can affect significantly biogeochemical cycles, hence, affecting the whole global climate. Although numerous studies have documented the effects of wildfires on hydrological and erosion processes, the effects of fire on the quantity (in terms of stocks and losses of OC content by overland flow) and quality of SOM and in the sediments eroded, as well on postfire SOM recovery, have received considerably less research attention. These were the principal goals of the present study conducted on eucalypt plantations, one of the most fire-prone forest types in northcentral Portugal. The effects of wildfires on quality of SOM was evaluated in topsoil samples (0-2 cm) on four sampling occasions, starting immediately after the first post-fire rain till two years later. It was necessary a combination of multi-analytical techniques, such as lipid-biomarker analysis by gas chromatography-mass spectrometry (GC-MS), SOM characterization by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and solid state 13C nuclear magnetic resonance (13C NMR) spectroscopy. Post-fire OC exports by overland flow and the contributions of the dissolved organic carbon (DOC), particulate organic carbon (POC) and dissolved inorganic carbon (DIC) fractions were measured in runoff samples collected at 1- to 2- weekly intervals during the first year after the wildfire. The results showed that wildfire produced substantial changes in the quantity and quality of SOM. These included the thermal breakdown and cracking of n-alkyl compounds. Ratios of short-to-long n-alkanes and n-fatty acid methyl esters (FAMEs) increased and typical carbon number predominance indexes for n-alkanes (odd-to-even) and n-FAMEs (evento- odd) were altered. Furthermore, the relative abundances of certain markers, which are plantspecies specific were modified, especially by decreasing terpenoids such as epiglobulol, ledol and globulol, which are characteristic of Eucalyptus globulus. Other differences observed in the burnt soil were the appearance of levoglucosan, a typical marker for the thermal alteration of polysaccharides, larger relative abundances of lignin-derived compounds (vanillin and methoxyphenols) and the presence of N-heteroaromatic structures. The 13C NMR spectra also indicated that the wildfire produced a considerable increase in the aromaticity and aromatic condensation of the topsoil SOM. The continuation of these differences in SOM quality during the period of this study, suggested a slow recovery of soil properties, possibly influenced by a limited recovery of the vegetation after the fire combined with the fire-enhanced losses of soil. The present work also evaluated post-fire soil OC losses by overland flow in recently two burnt eucalypt plantations, addressing a topic that has seldom been investigated. The main findings were that: (i) the amount of deposited ashes was higher at the NW slope than at the SE slope, while ashes total organic carbon (TOC) content revealed no differences; (ii) total sediment losses and also the TOC export were higher at the NW slope than at the SE slope; (iii) particulate organic carbon fraction showed the highest loss at the both topsoil sites. In addition, this study provides some insight into post-fire organic carbon losses in the recently burnt areas, which is crucial information for ecosystem management, especially in terms of soil fertility.
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Hakamada, Rodrigo Eiji. "Uso do inventário florestal como ferramenta de monitoramento da qualidade silvicultura em povoamentos clonais de Eucalyptus." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-05072012-100431/.
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A produtividade florestal é definida pelo ambiente de produção em que o povoamento está inserido, pela implantação de materiais genéticos superiores e pelo seu correto manejo silvicultural. A correta prescrição de recomendações silviculturais e a execução das operações de maneira padronizada tem por objetivo eliminar ou minimizar as restrições ao crescimento para cada árvore. Apesar das melhorias silviculturais que ocorreram nas últimas décadas, sabe-se que ainda é possível ganhos em produtividade através do monitoramento, detecção e correção precoce de desvios na qualidade silvicultural. Assim, o objetivo deste trabalho foi investigar um índice para o monitoramento da qualidade silvicultural utilizando uma rede de inventário florestal. Para isto, foram realizadas três etapas de trabalho: i) Definição de índices de uniformidade das variáveis dendrométricas; ii) Padronização dos chamados intervalos ótimos de uniformidade (IOU) e iii) Validação da metodologia via sua aplicação numa rede de inventário florestal para um único clone comercial. Na primeira etapa utilizaram-se três ensaios da rede BEPP (Brasil Eucalyptus Produtividade Potencial) com diferentes níveis de produtividade para estabelecer os índices adequados em caracterizar a uniformidade silvicultural. Na segunda etapa utilizaram-se cinco testes clonais de Eucalyptus no Estado de São Paulo para validar o conceito de Intervalo Ótimo de Uniformidade. Na última etapa, os índices e conceito do IOU foram aplicados em escala comercial em uma rede de parcelas de inventário florestal instalada em 12.000 hectares de plantios clonais de Eucalyptus no Nordeste do Estado de São Paulo, com cerca de 2 anos de idade, e plantados no período de 1995 a 2009. Na fase de definição, o índice que representa a porcentagem do volume total existente em 50% das menores árvores plantadas (o que inclui as falhas de plantio) (PV50) se mostrou como o que melhor se adequou à proposta do trabalho, pois possui limites finitos (50% a 0%), contempla as falhas de plantio como parte do índice de uniformidade do povoamento e, indiretamente, representa a distribuição de classes de crescimento. As uniformidades aos 5, 9, 12 e 24 meses foram fortemente correlacionadas à uniformidade aos 6 anos (r² > 0,74) mostrando a possibilidade de monitoramento precoce para detecção de desvios de qualidade na silvicultura. Além disso, o índice PV50 inicial foi altamente correlacionado com a produtividade final (p < 0,001). Na fase de padronização, não se detectou diferença estatística (Tukey, 5%) do PV50 entre os testes clonais a despeito de suas distintas produtividades, evidenciando que o índice de uniformidade pode ser generalizado, independentemente da produtividade do sítio. O IOU do PV50 foi de 34 a 50 %, ou seja, parcelas amostrais que possuírem o PV50 dentro deste intervalo podem ser consideradas satisfatoriamente uniformes. Na etapa de validação, quando o conceito foi aplicado em escala comercial observou-se uma forte evolução temporal do PV50. Nos plantios realizados em 1995 a média do índice foi de 29% e elevou-se para 42% em 2009. O percentual de parcelas dentro do intervalo ótimo de uniformidade tendeu claramente a se elevar ao longo deste período, devendo estar relacionada com as melhorias nas principais operações silviculturais e seu monitoramento através do controle de qualidade.Forest productivity is defined by the environment the population is inserted, by the implementation of genetically superior material and by the correct silvicultural management applied at this material. The correct prescription of technical recommendations and the execution of those operations according to acceptable quality standard are intended to eliminate or minimized the growth constrains. Despite the silvicultural improvements that have occurred in recent decades, it is known that it is still possible to obtain gains in productivity through monitoring, early detection and correction of deviations in the silviculture. The objective of this study was to investigate an index for monitoring the silvicultural quality using forest inventory networks. For this, there were three stages of work: i) Definition of uniformity indexes of dendrometric variables; ii) Standardization of so-called optimal range of uniformity (ORU) and validation of the methodology through its application in a network of forest inventory for a single commercial clone. In the first stage we used three tests of the network BEPP (Brazil Eucalyptus Potential Productivity) with different levels of productivity to establish the appropriate indexes to characterize the silvicultural uniformity. In the second stage we used five clonal test of Eucalyptus in Sao Paulo state to validate the concept of Optimum Range of Uniformity. In the last step, the indexes and the concept of IOU were applied on a commercial scale in a network of forest inventory plots installed in 12.000 hectares of Eucalyptus clonal plantations in northeastern of São Paulo state, with about 2 years old, and planted within 1995 to 2009. In the definition phase, the index that represents the percentage of the total volume of 50% of smaller trees planted (which includes the planting holes) (PV50) was shown as the best adapted to the purpose of this study because it has finite limits (50% to 0%), includes the holes of planting and indirectly represents the distribution of classes of growth. The uniformity at 5, 9, 12 and 24 months were strongly correlated to uniformity to 6 years (r² > 0.74) showing the possibility of early monitoring for detection of quality deviations in forestry. Furthermore, the initial rate PV50 was highly correlated with the final yield (p <0.001). At the stage of standardization, there was no statistical difference (Tukey, 5%) of PV50 among clonal tests despite their different yields, showing that the uniformity index can be generalized, irrespective of the productivity of the site. The ORU of PV50 was from 37 to 50%, i.e., sample plots which have the PV50 within this range can be considered satisfactory \"uniform\". In the validation phase, when the concept was applied on a commercial scale there was a strong temporal evolution of PV50. In the plantations made in 1995 the average of PV50 was 29% and increased to 42% in 2009. The percentage of plots within the optimal range of uniformity clearly tended to rise over this period and could be related to major improvements in forestry operations and their monitoring through quality control.
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Rodrigues, Fernando Antonio Vieira. "Disponibilidade de cobre e zinco para mudas de eucalipto em solos de Cerrado." Universidade Federal de Viçosa, 2009. http://locus.ufv.br/handle/123456789/5417.
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Previous issue date: 2009-02-18Conselho Nacional de Desenvolvimento Científico e Tecnológico
Brazil is one of the biggest producers of cellulose, paper and vegetal coal of the world, and the activities related to planted forests contribute to 3.5 % of the Gross Domestic Product (PIB) of the country. The eucalypt is the forest essence that stands out, with a planted area of 3.75 millions of hectares, and the state of Minas Gerais has about 28 % of this planted area. In Brazil, with the intensification of the clonal sivilculture, the management of genetic materials that are more productive and more nutritional demanding has increased the appearance of symptoms of micronutrients deficiency, mainly of B, and, more recently, of Cu and Zn, especially in areas of Cerrado. The aim of this study was to evaluate three methods of determining Cu and Zn availability (Mehlich-1, Mehlich-3 and DTPA pH 7.3) to eucalypts seedlings cultivated under greenhouse conditions, in samples of six soils from Minas Gerais state (one sample from João Pinheiro, two from Vazante, one from Três Marias and two from Curvelo) and the influence of the properties of the soil in the efficiency of these extractors. Were realized two experiments, one for each micronutrient. The treatments were arranged in a randomized block design, with four replications, in a factorial scheme of 6 x 5, corresponding to six soils and five doses of micronutrient. The doses were 0, 2, 4, 8 and 16 mg dm-3 of Cu and 0, 2.5, 5, 10 and 20 mg dm-3 of Zn, in the form of Cu and Zn chloride, respectively. After 70 days of growth, the plants were cut into two distinct portions, one being apical (apical third of all the branches of the plant) and the other being basal (the rest of the plant cut down near the ground level). The criticals levels of Cu and Zn in soils from Cerrado, to the growth of eucalypts seedlings, are equal or inferiors to 0.12 and 0.23 mg dm-3 by the Mehlich-1 and are equal or inferiors to 0.09 and 0.05 mg dm-3 by the DTPA, respectively. The concentrations of Cu and Zn in the soil and in the plant, as well as the respectives contents, increase with the elevation of the additional doses of these nutrients. The concentrations and the contents of Cu and Zn in the plant show close relation to the contents extracted by the three extractors. The concentrations of Cu and Zn extracted by Mehlich-1, Mehlich-3 and by DTPA were strongly correlated. The content of organic matter and the P- remanescent are the characteristics of the soils which most negatively influence in the recovering rates of Cu and Zn by the extractors Mehlich-1 and Mehlich-3, while for the DTPA, the recovering rates are more negatively influenced by the pH. The Mehlich-1 is the most recommended extractor to evaluate Cu and Zn availability to eucalypts seedlings. First because the method is easy to handle when compared to other methods, and second because it is a method which has already been used by the great majority of the labs in the country.
O Brasil é um dos maiores produtores de celulose, papel e carvão vegetal do mundo, e as atividades relacionadas às florestas plantadas contribuem com 3,5 % do Produto Interno Bruto (PIB) do país. O eucalipto é a essência florestal que se destaca, com uma área plantada de 3,75 milhões de hectares e o Estado de Minas Gerais possui em torno de 28 % dessa área plantada. No Brasil, com a intensificação da silvicultura clonal e o plantio de materiais genéticos mais produtivos e exigentes nutricionalmente têm aumentado o aparecimento de sintomas de deficiência de micronutrientes, principalmente de B, e, mais recentemente, de Cu e Zn, especialmente em áreas de Cerrado. Este trabalho teve por objetivo avaliar três métodos de determinação da disponibilidade de Cu e de Zn (Mehlich-1, Mehlich-3 e DTPA pH 7,3) para mudas de eucalipto cultivadas em casa de vegetação, em amostras de seis solos do Estado de Minas Gerais (um de João Pinheiro, dois de Vazante, um de Três Marias e dois de Curvelo) e a influência de propriedades do solo na eficiência desses extratores. Foram realizados dois experimentos, um para cada micronutriente. Os tratamentos foram arranjados no esquema fatorial 6 x 5, correspondendo a seis solos e cinco doses do micronutriente, com quatro repetições, em blocos ao acaso. As doses foram de 0, 2, 4, 8 e 16 mg dm-3 de Cu e de 0, 2,5, 5, 10 e 20 mg dm-3 de Zn, na forma de cloreto de Cu e Zn, respectivamente. Após 70 dias de crescimento, as plantas foram cortadas em duas porções distintas, sendo uma apical (terço apical de todos os ramos da planta) e a outra basal (restante da planta cortada rente ao solo). Os níveis críticos de Cu e de Zn em solos de Cerrado, para o crescimento de mudas de eucalipto, são iguais ou inferiores a 0,12 e 0,23 mg dm-3 pelo Mehlich-1 e iguais ou inferiores a 0,09 e 0,05 mg dm-3 pelo DTPA, respectivamente. Os teores de Cu e de Zn no solo e na planta, bem como os respectivos conteúdos, aumentam com a elevação das doses adicionadas desses nutrientes. Os teores e conteúdos de Cu e de Zn na planta mostram estreita relação com os teores extraídos pelos três extratores. Os teores de Cu e de Zn extraídos pelo Mehlich-1, Mehlich-3 e DTPA são altamente correlacionados entre si. O teor de matéria orgânica e o P-remanescente são características dos solos que mais influenciam negativamente nas taxas de recuperação de Cu e de Zn pelos extratores Mehlich-1 e Mehlich-3, enquanto que para o DTPA, as taxas de recuperação são mais influenciadas pelo pH. O Mehlich-1 é o extrator mais recomendado para avaliar a disponibilidade de Cu e de Zn para mudas de eucalipto, pela facilidade operacional deste método frente aos outros e por este já ser usado na grande maioria dos laboratórios do país.
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De, Marchi Tiago Closs. "Influência do gado e da monocultura de eucalyptus sp. em florestas ripárias do sul do Brasil." Universidade do Vale do Rio dos Sinos, 2011. http://www.repositorio.jesuita.org.br/handle/UNISINOS/3969.
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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A mudança do uso da terra decorrente de atividades agrícolas provoca uma modificação na paisagem que leva à criação de fragmentos florestais isolados que se mantém imersos em uma matriz que pode apresentar uma maior ou menor agressividade de acordo com o seu uso. Este estudo foi realizado em duas fazendas vizinhas localizadas no município de Eldorado do Sul, RS. A Fazenda Terra Dura, pertence à empresa Celulose Riograndense S/A e a maior parte da área é utilizada para a monocultura de eucalipto (Eucalyptus spp.). Os remanescentes de floresta nativa estão exclusivamente associados aos diversos cursos d’água que cruzam a área e cercados pelo plantio de eucalipto de diversas idades e estágios de produção. A área é utilizada para o plantio de eucalipto há cerca de 30 anos e há 20 foi isolada do gado. A Fazenda Eldorado destina-se à criação extensiva de gado e sua cobertura vegetal é caracterizada por um predomínio de campo com fragmentos de florestas ripárias que o gado utiliza como local de pastejo e desedentação. Em cada uma das dez áreas selecionadas foram alocados dois transectos paralelos ao curso d’água a 20 metros de distância um do outro nos quais foram aleatorizadas cinco unidades amostrais de 10 x 10m para amostragem do componente arbóreo dos fragmentos. Em cada unidade amostral foram registradas a circunferência de todos os indivíduos com diâmetro a altura do peito maior ou igual a 5 cm (DAP ≥ 5cm). O componente juvenil foi amostrado em unidades amostrais de 5 x 5m concêntricas em cada parcela de 10 x 10m, onde foram amostrados todos os indivíduos com mais de um metro de altura e com menos de 5 cm de diâmetro e estimou-se sua altura total e seu diâmetro à altura do solo (DAS). A densidade e composição do estrato herbáceo foi amostrada em parcelas de 1 x 1 m concêntricas às unidades amostrais de 5 x 5 m. Nestas unidades amostrais foi removida toda vegetação de até 1 m de altura e identificadas taxonômicamente as espécies e separadas em formas de vida (árvore, arbusto, erva, gramíneas, pteridófita, trepadeiras, epífitos). Para avaliação do sub-bosque nos plantios de eucalipto foram selecionados quatro talhões onde foram alocados três transectos de 100 m de comprimento em diferentes distâncias da borda (5, 25 e 50 m) e dois transectos (5 e 25 m) para o interior da mata ciliar. Em cada transecto foram sorteadas cinco unidades amostrais de 5 x 5 m e amostrados todos os indivíduos juvenis utilizando os mesmos critérios anteriormente citados para este estrato. Nos fragmentos adjacentes aos plantios de eucalipto, foram encontradas 61 espécies para os adultos e 77 para os juvenis e o estoque de carbono estimado foi de 106 Mg.ha-1 para os indivíduos adultos e de 4,3 Mg.ha-1 para os herbáceos. Nas áreas com presença de gado foram amostradas 62 espécies para os adultos e 48 para juvenis, com um estoque de carbono de 85,5 Mg.ha-1 para adultos e 0,9 Mg.ha-1 para herbáceo. No sub-bosque dos plantios de eucalipto foram amostradas 32 espécies, sendo 16 exclusivas e 71 no interior da floresta ripária, com 55 exclusivas. Os resultados mostraram que florestas em pequenos fragmentos incorporados em plantações de eucalipto parecem ser melhor preservadas do que aqueles expostos à pecuária. Além disso, áreas com presença de gado apresentaram uma redução no estoque de carbono de 23,8% para o estrato arbóreo e de 79,4% no estrato herbáceo em relação às áreas sem a presença de gado. A plantação de eucalipto possui um importante papel, embora restrito devido ao curto período de corte das árvores, para a manutenção da diversidade de espécies de florestas nativas adjacentes em seu sub-bosque e podem atuar como uma catalizadoras da regeneração da vegetação nativa e na manutenção da diversidade local.
The change in land use due to agricultural activities causes a landscape change that leads to the creation of isolated forest fragments that remain embedded in a matrix that may present a greater or lesser aggressiveness according to their use. The environmental quality of this matrix can affect species composition and forest structure through several factors that impact the surrounding environment, but on the other hand, depending on its type, the array can act as an important source of biodiversity conservation. This study was conducted in two neighboring farms located in Eldorado do Sul, RS. Terra Dura Farm, owned by Celulose Riograndense S/A and most of the area is used for the monoculture of eucalyptus (Eucalyptus spp.). The remnants of native forest are exclusively associated with the various streams that cross the area and surrounded by eucalyptus plantations of various ages and stages of production. The area is used for the planting of eucalyptus during 30 years. The cattle was isolated 20 years ago. Eldorado Farm is intended for extensive cattle ranching and its vegetation is characterized by a predominance of field with fragments of riparian forests that livestock use for grazing. We survey ten riparian fragments, five in each farm, were allocated two transects parallel to the stream to 20 m away from each other in which five were randomized plots of 10 x 10 m sampling of the tree component of the fragments. In each sampling unit circumference were recorded for all individuals with diameter at breast height greater than or equal to 5 cm (DBH ≥ 5 cm). The juvenile component was sampled in 5 x 5 m plots concentric in each plot of 10 x 10 m was sampled all individuals with more than one meter in height and less than 5 cm in diameter and estimated its total height, and its diameter at ground level (DAS). The density and composition of the herbaceous layer was sampled in plots of 1 x 1 m plots of concentric to 5 x 5 m. In these sample units of all vegetation was removed up to 1 m high, which were taxonomically identified and separated in life forms (tree, shrub, herb, grass, fern, lianes and epiphytes). To evaluate the understory in the eucalyptus plantations were selected four plots were allocated three transects of 100 m length at different distances from the edge (5, 25 and 50 m) and two transects (5 and 25 m) into the riparian vegetation. In each transect were randomly selected five samples of 5 x 5 m and sampled all juveniles using the same criteria previously cited for this stratum. In fragments adjacent to eucalyptus plantations, 61 species were found for adults and 77 for juveniles and the estimated carbon storage was 106 Mg.ha-1 for adults and 4.3 Mg.ha-1 for the herbs. In areas with presence of cattle were sampled for 62 adults and 48 for juveniles, with a carbon stock of 85.5 Mg.ha-1 for adults and 0.9 Mg.ha-1 for herbaceous. In the understory of the eucalyptus plantations were found 32 species, with 16 exclusive and 71 within the riparian forest, with 55 exclusive. Our results showed that in small forest fragments embedded in eucalypt plantations seem to be better preserved than those exposed to livestock. In addition, areas with the presence of cattle showed a reduction in carbon stock of 23.8% for the upper stratum and 79.4% in the herbaceous layer compared to areas without the presence of livestock and the planting of eucalyptus has an important role, although limited, due to shortcut the trees for the maintenance of species diversity of native forest adjacent to their understory and can act as a catalyst of the regeneration of native vegetation and maintenance of local diversity.
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Soares, Márcia Toffani Simão. "Taxas de mineralização e de lixiviação do nitrogênio, e alterações da fertilidade de um latossolo vermelho-amarelo degradado e outro não-degradado fertilizados com biossólido e florestados com Eucalyptus grandis." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-02032006-153459/.
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Este estudo teve como objetivo avaliar os efeitos da aplicação de biossólido sobre as taxas de mineralização e de lixiviação de N, as modificações de fertilidade do solo, a nutrição e o crescimento de povoamentos de Eucalyptus grandis plantados em um Latossolo Vermelho-Amarelo Distrófico não-degradado (sob cultivo mínimo) e outro degradado. O experimento foi conduzido no município de Salto de Pirapora, SP. A área experimental foi constituída de quatro blocos e nove tratamentos; em três tratamentos, a camada superficial do solo (0-20cm) foi removida (solo degradado). Os tratamentos na área com solo não-degradado, cultivado no sistema de cultivo mínimo, foram: (1) Controle, (2) Fertilização mineral, (3) 10 t ha-1, (4) 20 e (5) 40 t ha-1 de biossólido (base seca), todos com suplementação de P e K, e (6) 10 t ha-1 de biossólido, sem suplementação de P e K; na área com solo degradado, os tratamentos foram: (7) Controle, (8) 20 e (9) 40 t ha-1 de biossólido, todos com suplementação de P e K. Nos tratamentos 1, 4 e 8 foram monitoradas as taxas de mineralização e de lixiviação de N no solo. No solo não-degradado, nos primeiros sete meses pós-aplicação do biossólido (PAB), houve aumento das taxas de mineralização de N, do pH, da concentração de P resina, e diminuição das concentrações de K, Ca e Mg trocáveis. Aos doze meses PAB, as concentrações de P-resina aumentaram, e as de matéria orgânica e N total diminuíram. As concentrações foliares de N aumentaram aos três meses, de N e P aos sete meses, e as de K diminuíram aos doze meses PAB. No solo degradado que recebeu 20 t ha-1 de biossólido, as quantidades de N mineralizadas, em sete meses, foram semelhantes às obtidas no não-degradado sem biossólido, e as taxas de lixiviação de N foram maiores do que no solo não-degradado com a mesma dose. Nesta época, no solo degradado, o biossólido aumentou concentrações de P-resina, Ca, Mg e S, o pH somente na camada 0-3 cm e, aos doze meses, aumentou as concentrações de C, N totais, de matéria orgânica, de P-resina, de Ca trocável, e diminuiu e aumentou, respectivamente, as concentrações de S nas camadas 0-3 e 3-30 cm do solo. Houve aumento das concentrações foliares de N, aos três meses, de N, P, Mg e S aos sete meses, e de Ca aos doze meses PAB. O biossólido aumentou as taxas de crescimento do E. grandis, aos sete meses PAB, nas duas condições de solo e, aos doze e aos vinte e dois meses PAB, nos tratamentos em solo degradado. No tratamento em solo degradado que recebeu 40 t ha-1 de biossólido, as árvores tiveram crescimento semelhante ao dos tratamentos em solo não-degradado. Nas duas condições de solo, as variâncias entre tratamentos relativas ao crescimento das árvores foram explicadas principalmente pela maior absorção de N pelas plantas.The aim of this study was to evaluate the effects of biosolid application on the mineralization and leaching rates of N, the changes of soil fertility, nutrition and growth of Eucalyptus grandis cultivated in a non-degraded (under minimum tillage) and in a degraded Red-Yellow Latosol (Oxissol). It was carried out in Salto do Pirapora district, São Paulo State, Brazil. The experimental area included four blocks and nine treatments; in three of them, the topsoil (0-20cm) was removed (degraded soil). Treatments in the non-degraded soil area, cultivated under minimum-tillage system, were: (1) Control, (2) Mineral fertilization, (3) 10 t ha-1, (4) 20 and (5) 40 t ha-1 of biosolid, all supplemented with P and K and (6) 10 t ha-1 of biosolid with no P and K supplementation; in the degraded soil area, the treatments were: (7) Control, (8) 20 and (9) 40 t ha-1 of biosolid, all supplemented with P and K. Mineralization and leaching rates of N in the soil were monitored in treatments 1, 4 and 8. In non-degraded soils, on the first seven months after biosolid application (ABA), increasing of N mineralization rates, pH, concentration of the soil P-resin, and decreasing concentrations of exchangeable K, Ca and Mg were observed. Twelve months ABA, P-resin concentrations increased, and organic matter and total N decreased. N concentration in foliage increased at three months, N and P at seven months and K decreased at twelve months FBA. The amounts of mineralized N in the degraded soil with biosolid (20 t ha-1), at seven months, were similar to those achieved in the Control under non-degraded soil; N leaching was higher in degraded than those in non-degraded soil with the same amount of biosolid. In that age, in degraded soil, the biosolid increased the concentrations of P-resin, Ca, Mg and S and pH, only at 0-3 cm layer and, at twelve months, increased the total C and N, organic matter, P-resin, exchangeable Ca, and S concentrations decreased in 0-3 and increased in 3-30 cm layers. N, P, Mg and S concentrations in foliage increased at seven months and Ca at twelve months ABA. The biosolid increased the growth rates of E. grandis at seven months ABA in both soil conditions, and at twelve and twenty-two months ABA in degraded soil. In degraded soil treatment that received 40 t ha-1 of biosolid, the growth of trees was similar to those of non-degraded soil treatments. In both soil conditions, the variances between treatments regarding tree growth were explained mainly by higher plants N uptake.
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Gruber, Yanê Borges Garcia. "Otimização da lâmina de irrigação na produção de mudas clonais de eucalipto (Eucalyptus urophylla x Eucalyptus grandis e Eucalyptus urophylla var. plathyphylla)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11143/tde-19062006-153010/.
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Com o objetivo de otimizar a lâmina de irrigação aplicada durante a produção de mudas clonais de eucalipto, por intermédio de avaliações morfológicas, foram conduzidos três experimentos (E1 verão 2003, E2 inverno 2003 e E3 verão 2004) no viveiro de mudas da empresa Eucatex S/A, em pátio de pleno sol, por 56 dias e apresentaram delineamento em blocos casualizados, no esquema de faixas. Os tratamentos constituíram-se de 4 lâminas de irrigação (H0 testemunha, H1, H2 e H3), aspergidas sobre o dossel e 2 clones (E. urophylla x E. grandis CA e E. urophylla var. plathyphylla CB). Foram avaliados: diâmetro de caule (DC), altura da parte aérea (HPA), área foliar (AF), massa seca foliar (MSF), caulinar (MSC), da parte aérea (MSPA), radicular (MSR) e total (MST), em função da idade (dias após estaquia) e por meio dos rendimentos na produtividade, proporcionados pelos níveis de lâmina total aplicada. Os parâmetros climáticos coletados foram: temperatura do ar, umidade relativa do ar, evaporação e chuva. Os tratamentos influenciaram no crescimento das mudas. Durante E1, a lâmina irrigada (LI) variou entre 292,54 mm no nível H0 e 65,09 mm no nível H3. Com o acréscimo da chuva (304,6 mm), a lâmina total (LT) aplicada sobre o dossel variou entre 597,14 e 369,69 mm nos níveis H0 e H3, respectivamente. A chuva ocorrida no período influenciou muito na irrigação. O clone CB proporcionou o maior crescimento, sendo a LT H2 considerada a mais adequada (426,46 mm). A faixa de água responsável pela máxima produtividade variou entre 369,69 mm (MSR) e 508,22 mm (MSC) para o clone CA e entre 435,49 mm (MSC) e 475,01 mm (HPA) para o clone B. Recomenda-se a aplicação de uma lâmina diária estimada (LDE) em torno de 7,6 mm.dia-1. Durante E2, a LI variou entre 399,934 mm no nível H0 e 69,92 mm no nível H3. A lâmina de chuva (LC) foi de 55 mm elevando a LT para 443,93 e 124,92 mm nos níveis H0 e H3, respectivamente. A irrigação foi a principal fonte de aplicação de água. O clone CA garantiu o maior crescimento, sendo a LT do nível H1 (330,75 mm) responsável pelos incrementos superiores. Os pontos de ótimo produtivo foram obtidos com a lâmina máxima (Lmax) entre 328,49 mm (MSF) e 359,69 mm (HPA) para CA e entre 338,47 mm (MSF) e 388,55 mm (DC) para CB. É recomendada a utilização de uma LDE de 6 mm.dia-1. No E3, a LI variou entre 402,90 e 69,35 mm para os níveis H0 e H3, respectivamente. A LC foi de 235,08 mm. A LT variou entre 638,73 mm em H0 e 305,13 mm em H3. O melhor nível de aplicação hídrica foi o H1, com LT de 520,47 mm, sendo o CA o clone com maior crescimento. As Lmax responsáveis pela maior rentabilidade foram entre 523,48 mm e 564,97 mm, para os parâmetros HPA e DC, respectivamente, no caso do clone CA e entre 511,23 mm (MSR) e 544,24 mm (MSF) para o clone CB. A LDE recomendada foi em torno de 9,3 mm.dia-1. Durante a fase de crescimento, conclui-se que a água aplicada pela testemunha (H0) é maior do que as necessidades hídricas das mudas de eucalipto.With the purpose of optimizing the applied irrigation depth during the production of eucalypts (clone seedlings), through morphologic evaluations, three experiments (E1 - summer 2003, E2 - winter 2003 and E3 - summer 2004), during 56 days, were carried out in the nursery forest (opened field) of the Eucatex S/A Company, using randomized blocks statistical design (with sub-plots in strips). The treatments were constituted of 4 irrigation depth (H0 - control, H1, H2 and H3), sprinkled on the canopy and 2 clones (E. urophylla x E. grandis - CA and E. urophylla var. plathyphylla - CB). The stem diameter (DC), the height of the aerial part (HPA), the leaf area (AF) and the dry mass of leaf (MSF), stem (MSC), aerial part (MSPA), root (MSR) and total (MST) were evaluated in function of the age (days after cutting) and through the incomes in the productivity, proportionate for the levels of applied total sheet. The collected climatic parameters were: temperature of the air, relative humidity of the air, evaporation and rain. The treatments influenced in the growth of the seedlings. During E1, the irrigated depth (LI) it varied among 292.54 mm in the level H0 and 65.09 mm in the level H3. With the increment of the rain (304.6 mm), the total sheet (LT) applied on the dossal it varied between 597.14 and 369.69 mm in the levels H0 and H3, respectively. The rain happened in the period influenced a lot in the irrigation. The clone CB provided the largest growth, being LT considered H2 the most appropriate (426.46 mm). The strip of responsible water for the maxim productivity varied among 369.69 mm (MSR) and 508.22 mm (MSC) for the clone CA and among 435.49 mm (MSC) and 475.01 mm (HPA) for the clone B. the application of a dear daily sheet is Recommended (LDE) around 7.6 mm.day-1. During E2, LI varied among 399.934 mm in the level H0 and 69.92 mm in the level H3. The rain sheet (LC) it was of 55 mm elevating LT for 443.93 and 124.92 mm in the levels H0 and H3, respectively. The irrigation was the main source of application of water. The clone CA guaranteed the largest growth, being it LT of the level H1 (330.75 mm) responsible for the superior increments. The points of great productive they were obtained with the maximum sheet (Lmax) among 328.49 mm (MSF) and 359.69 mm (HPA) for CA and among 338.47 mm (MSF) and 388.55 mm (DC) for CB. The use of a LDE of 6 mm.day-1 is recommended. In E3, LI varied between 402.90 and 69.35 mm for the levels H0 and H3, respectively. LC was of 235.08 mm. LT varied among 638.73 mm in H0 and 305.13 mm in H3. The best level of water application was H1, with LT of 520.47 mm, being CA the clone with larger growth. Responsible Lmax for the largest profitability were between 523.48 mm and 564.97 mm, for the parameters HPA and DC, respectively, in the case of the clone CA and among 511.23 mm (MSR) and 544.24 mm (MSF) for the clone CB. Recommended LDE and around 9.3 mm.day-1. During the growth phase, it is ended that the applied water for the witness (H0) it is larger than the water needs of the eucalyptus seedlings.
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Castro, Diana Carolina Vasquez. "Planejamento da qualidade dos processos silviculturais na cultura do eucalipto no Brasil." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-28042017-164123/.
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O setor florestal tem grande importância econômica na formação do PIB interno do Brasil e o reflorestamento contribui para a redução do desmatamento das florestas nativas. A demanda crescente pela cultura do eucalipto exige do setor florestal a busca pela competitividade, e essa competitividade está associada à produtividade. A produção do eucalipto é uma atividade complexa que envolve inúmeras variáveis interligadas e o bom desempenho dessas variáveis garante o sucesso da cultura. Nesse contexto o planejamento do processo produtivo é de fundamental importância para definir as variáveis que podem influir no desenvolvimento das arvores e consequentemente na produtividade e assim contribuir na otimização dos recursos. Para tanto, é necessário conhecer as demandas da cultura definindo as variáveis que podem influenciar tanto na produtividade quanto na qualidade. Com isso, o objetivo principal do trabalho foi identificar as características técnicas prioritárias para atender as exigências das operações silviculturais para a produção de eucalipto e avaliar se essas características estão sendo atendidas dentro dos padrões necessários na fase de execução dos processos. A metodologia empregada foi a função desdobramento da qualidade (QFD) tendo como cliente o eucalipto. O trabalho foi realizado na Companhia Suzano de Papel e Celulose, localizada no Estado de São Paulo, BR. A metodologia permitiu traduzir as demandas do eucalipto em características técnicas, 79 no total, e os valores a serem atribuídos a essas características devem ser avaliados, devido às correlações existentes entre elas. Essas correlações podem trazer benefícios quando positivas, mas também podem influenciar negativamente o desenvolvimento da cultura. Com base nos resultados da identificação das características técnicas prioritárias, a profundidade de subsolagem e a qualidade do plantio foram avaliadas a campo em duas áreas, localizadas na região de Itirapina e Agudos no estado de São Paulo. Os resultados mostram que embora as profundidades de subsolagem atendem ao especificado, o processo não está sob controle. Já para a qualidade do plantio o processo está sob controle nas áreas avaliadas.The forestry sector is one of the primary sectors that contribute significantly to the Brazilian GDP and reforestation contributes to the reduction of deforestation of native forests in the country. The growing demand for eucalyptus crop requires the forestry sector to be competitive, and this competitiveness is associated with productivity. Eucalyptus production is a complex activity that includes several interrelated variables, and the good performance of these variables ensures the success of the crop. In this context the planning of the productive process is fundamental importance to define the variables that can influence the development of the trees and consequently in the productivity and thus contribute with the optimization of the resources. To define the variables that can influence both productivity and quality, it is necessary to know the crop demand. Therefore, the main objective of this study was to identify the priority technical characteristics in order to meet the silvicultural operations requirements for eucalyptus production, and to evaluate whether or not these characteristics meet the standards in the process execution phase. The methodology used was the quality function deployment (QFD), and the customer was the eucalyptus. The search was carried out at Suzano Pulp and Paper Company, located in the State of São Paulo, Brazil. The demand for eucalyptus was converted into technical characteristics, 79 total, and the values to be attributed to these characteristics should be evaluated, due to the correlation between them. These correlations can bring benefits when positive, but they can also negatively impact the development of the crop. The results obtained from the priority technical characteristics show that the subsoiling depth and the quality of the planting were evaluated in the field in two areas in the region of Itirapina and Agudos in the state of São Paulo. The outcomes show that although the subsoiling depths meet the specified depths, the process is not under control. On the other hand, in regards to the quality of the planting, the process is under control.
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Ruprecht, John. "Impact of forest disturbance on jarrah (Eucalyptus marginata) forest hydrology." Thesis, Ruprecht, John (2018) Impact of forest disturbance on jarrah (Eucalyptus marginata) forest hydrology. PhD thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/40880/.
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Globally, forests cover 31% of the Earth’s land mass and are critical areas for water supply. In Australia, forested catchments provide 77% of urban water supplies to capital cities. However, recent studies have reported worldwide examples of forest damage resulting from drought or heat related events. The jarrah (Eucalyptus marginata) forests of south-west Western Australia (SWWA) have experienced both sudden and unprecedented forest collapse and profound reductions in streamflows. Projected further declines with climate change, reinforce the need to understand the hydrologic impact of forest disturbance and what management responses are needed to enhance forest resilience and productive capacity.
The aim of this thesis was to understand the impact of disturbance and climate on the hydrology of the forests of SWWA, with objectives to:
1. Examine the characteristics of forest hydrology;
2. Evaluate the hydrologic response to forest disturbance and climate variability; and
3. Evaluate forest water management options in the context of forest disturbance and climate change.
This thesis thus develops an understanding of the impact of disturbance and climate on the hydrology of the forests of SWWA. Using hillslope and paired catchment studies (Chapter 3), it develops an understanding of the process of infiltration and soil water dynamics and examines the hydrologic impact of forest disturbance. The studies demonstrate the important roles of infiltration, soil water dynamics, and groundwater on the forest water balance, and identify the major factors that impact forest disturbance and forest hydrology. These studies have improved understanding of factors contributing to catchment water balance, and streamflow generation processes.
Four catchments underwent land use change and the impact on catchment hydrology was studied by comparing with a control catchment (Chapter 4). These paired catchment studies evaluated the impact of converting forest to agriculture and of timber harvesting. They explored the streamflow generation mechanisms for forested and cleared catchments, the streamflow generation and salinity export changes due to clearing for agriculture, and the hydrologic impact of intense timber harvesting for increased water production.
The impacts of deforestation, forest thinning, bauxite mining, bushfires, dieback disease, and reforestation were evaluated using several paired catchment studies across SWWA (Chapter 5). The long-term implications for management of water yield, the impact of a range of disturbances at a catchment scale, and the impact of forest disturbances on stream salinity are also examined.
The relationship between the drying climate observed in SWWA over the last 40 years and observed changes in rainfall, groundwater levels, streamflow volumes and flow duration were studied in Chapter 6. The changing relationship between rainfall and streamflow and the likely implications of recent climate change scenarios are also studied. The major forest water issues that have been identified in this thesis are the declining water values in forested areas, such as less water volumes, shorter flow periods, and declining groundwater levels.
The adaptive strategies for forest ecosystems are identified to include resistance (protect highly valued areas), resilience (improve capacity to return to pre-disturbance conditions) and response (assist transition to new condition) are discussed in Chapter 7. Drivers identified (Chapter 7) by this thesis include (a) a drying climate with direct and indirect impacts on both the forest itself and on the overall water balance, (b) responses to historical forest management including forest harvest, deforestation and reforestation, (c) long-term impacts of bauxite mining and subsequent rehabilitation, and (d) the interaction of these forest disturbances at a catchment scale.
The major findings from this study include:
- The high saturated hydraulic conductivity of the sandy gravel topsoil overlies lateritic durcirust with a much lower saturated hydraulic conductivity;
- The presence of large infilled “holes” within the lateritic duricrust;
- Saturation above the lateritic duricrust was observed confirming subsurface flow concepts;
- Presence of vertical preferential flow observed confirming soil water concepts;
- The critical importance of the groundwater discharge area in streamflow generation;
- Increase in stream salinity directly linked to groundwater levels approaching the surface;
- The time to leaching of the salt from the catchment estimated at 200 years;
- Forest disturbances such as clearing, timber harvesting and forest thinning led to increased streamflow but with significant delays related to the presence or lack of a groundwater discharge area; and
- The extensive reduction in streamflow across the south west has ranged from 36 to 52% (1975 to 2000 compared to 2001 to 2012) seen as a delayed response to rainfall reductions from 1930 to 2000.
The challenge for the future is for forest hydrology research to influence current and future forest management to improve environmental and water supply outcomes for the forests of not only SWWA, but globally. Understanding the impact of land-use change on hydrology, water quality and on water resources, and separating this from climate variability and change, is a recurring problem globally. Further understanding is thus needed of the causes of changing forest hydrology and of management options to ultimately improve forest outcomes.
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Salgado, Tiago Pereira [UNESP]. "Efeito do Glyphosate no crescimento, produção e qualidade da madeira do eucalipto (Eucalyptus grandis x E. urophylla)." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/105315.
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salgado_tp_dr_jabo.pdf: 919699 bytes, checksum: c2b46e671307dd0a1d6135456a265667 (MD5)O estudo foi realizado em duas etapas distintas. A primeira, composta por quatro ensaios, constou da aplicação de glyphosate (360 g e.a.L-1) em eucalipto. Em todos os ensaios, mudas foram transplantadas em vasos de 5,0 L. Nos ensaios 1 e 2, foram aplicados volumes de glyphosate no caule do eucalipto. No primeiro ensaio, uma solução de glyphosate na concentração de 3% (v/v) foi aplicada nas doses: 0, 1, 5, 10, 20, 40, 80 e 160 L.planta-1 e, no segundo, a solução a 2% (v/v) foi aplicada nas doses de: 0, 1, 5, 15, 30, 60, 90, 120 e 150 L.planta-1. Nos ensaios 3 e 4, foram feitas aplicações de glyphosate sobre o eucalipto. No ensaio 3 as doses foram: 0, 7,2.10-7, 7,2.10-6, 7,2.10-5, 7,2.10-4, 7,2.10-3, 7,2.10-2, 7,2.10-1, 7,2, 72, 360 e 720 g e.a de glyphosate.ha-1 e, no ensaio 4, as doses foram: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1080, 1440 e 2160 g e.a de glyphosate.ha-1. Nos quatro ensaios foi utilizado o delineamento DIC, com três repetições. Nas plantas foram avaliadas: altura, área foliar, matéria seca de caule e folhas. Os resultados obtidos foram submetidos a análises de regressao. Na segunda etapa, conduzida em campo, o mesmo clone de eucalipto foi plantado em 02/04/2004. Aos 1, 3, 5, 7 e 9 meses após o plantio (MAP), doses 0, 36, 72, 144, 288, 432 g e.a.ha-1 de glyphosate foram aplicadas sobre as plantas. O experimento foi montado em faixas de épocas de aplicação e doses do herbicida. As faixas tinham duas linhas de eucalipto por noventa metros, totalizando 90 plantas. Aos 10, 13, 26, 48 e 62 MAP foram feitas avaliações de altura e diâmetro. Com essas variáveis calculou-se o volume cilíndrico de madeira com casca. Ao final do ensaio (68 meses) foram feitas análises químicas de extrativos, lignina total, holoceluse e densidade basica da madeira nas doses de glyphosate aplicadas aos 5 MAP. Também foi avaliado o rendimento ao cozimento todas as épocas...
The study was conducted in two phase. The first, composed of four trials, consisted of the application of glyphosate (360 g a.e.L-1) on eucalyptus. In all the tests, seedlings were transplanted to pots of 5.0 L. In trials 1 and 2, it was applied volumes of glyphosate on the eucalyptus stem. In the first test, a glyphosate solution at 3% (v/v) concentration was applied in the. doses: 0, 1, 5, 10, 20, 40, 80 and 160 4.plant-1 and, in the second, the solution at 2% (v/v) was applied in the doses of: 0, 1, 5, 15, 30, 60, 90, 120 and 150 viL.plant-1. In the trials 3 and 4, it was made applications of glyphosate on eucalyptus. In the trial 3 doses were 0, 7,2.10-7, 7,2.10-6, 7,2.10-5, 7,2.10-a, 7,2.10-3, 7,2.10-2, 7,2.10-1, 7,2, 72, 360 e 720 g a.e of glyphosate.ha-1 and, in trial 4, the doses were: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1080, 1440 and 2160 g e.a of glyphosate.ha-1. In the fourth tests it was used the randomized completely design, with three replicates. Plants were evaluated by height, leaf area, dry matter of stem and leaves. The results obtained were submitted to regression analyzes. In the second stage, conducted in the field, the same eucalyptus clone was planted in 04-02-2004. At 1, 3, 5, 7 and 9 months after planting (MAP), doses 0, 36, 72, 144, 288, 432 g e.a.ha-1 of glyphosate were applied on the plants. The experiment was installed in strip tests of varying herbicide doses. The strips had two lines of eucalyptus by ninety meters, total of 90 plants. At 10, 13, 26, 48 and 62 MAP assessments were held in height and diameter. With these variables it was calculated the wood volume with bark. At the end of the trial (68 months) it was performed chemical analysis of extractives, lignin total holoceluse and basic wood density at doses of glyphosate applied at 5 MAP. It was also evaluated the wood cooking, in all times of application and doses of glyphosate... (Complete abstract click electronic access below)
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Habitzreiter, Tiago Luis. "Produção de biomassa e exportação de nutrientes de Eucalyptus grandis e E. urophylla." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/1717.
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A investigação científica na área de tecnologia de produção florestal busca técnicas que aumentem a produção por unidade de área, com alta viabilidade econômica e com redução dos impactos ambientais. Quando se tratam de plantios florestais, são necessários estudos da produção de biomassa e seu teor de nutrientes, sendo estes dados parâmetros para planejar as implicações ambientais de diferentes intensidades de colheita florestal. Diante do exposto, o presente estudo buscou elucidar a produção e exportação de biomassa e nutrientes para duas espécies do gênero Eucalyptus (E. grandis e E. urophylla) cultivadas na região sudoeste do Paraná. Para isso, foi avaliado: o estoque de biomassa e nutrientes na árvore (madeira, casca, galhos e folhas) aos 60 meses de idade do povoamento; a taxa de exportação de nutrientes; o poder calorífico e viabilidade econômica. A biomassa e os maiores estoques de nutrientes do eucalipto encontram-se predominantemente alocados no fuste (madeira + casca). Os componentes da biomassa apresentaram composições químicas distintas, sendo geralmente maiores nas folhas e casca e menores nos componentes madeira e galhos. Quanto ao poder calorífico, a folha teve seu poder calorífico estatisticamente superior às demais frações avaliadas, seguidas dos galhos, madeira e casca. O teor de Carbono orgânico (C.O.) está diretamente ligado ao poder calorífico, sendo que quanto maior o mesmo na fração, maior o poder calorífico. A madeira apresentou os maiores valores de eficiência de utilização de nutrientes, algo bastante desejável e de grande interesse para a silvicultura. Nas folhas estão os menores valores de eficiência de utilização de nutrientes, com exceção do Ca e Mg que estão na casca, indicando a importância da manutenção destes componentes no solo após a colheita. A fração madeira apresenta apresenta a biomassa de menor custo considerando o custo de reposição dos nutrientes exportado. Por outro lado, a fração de folhas apresentou o maior custo de reposição NPK.Scientific research in forest production technology area search techniques that increase production per unit area, with high economic viability and reducing environmental impacts. When dealing with forest plantations, studies are needed in the production of biomass and its nutrient content, and these are data parameters for planning the environmental implications of different intensities of forest harvesting. Given the above, this study aimed to elucidate the production and export of biomass and nutrients for two species of the genus Eucalyptus (E. grandis and E. urophylla) grown in the southwestern region of Parana. For this, it was evaluated: the stock of biomass and nutrients in eucalyptus (wood, bark, branches and leaves) at 60 months of age; the export rate of nutrients; the calorific value and economic viability. The biomass and the largest eucalyptus nutrient stocks are predominantly allocated to the stem (wood + bark). The components of biomass showed different chemical compositions, generally being higher in the leaves and bark and lower in wood and branches components. As for the calorific value, the leaves had its calorific value statistically superior than the other fractions, followed by branches, wood and bark. The organic carbon content (C.O.) is directly connected to the calorific value, and the calorific value increases as its content increase. The wood had the highest nutrient use efficiency values, something highly desirable and of great interest to forestry. The leaves showed smaller nutrient utilization efficiency values, with the exception of Ca and Mg that were smaller in the bark, indicating the importance of maintaining these components in the soil after harvest. The wood fraction presents the biomass lower cost when considering the replacement of nutrients exported by its biomass. On the other hand, the leaf fraction showed NPK higher cost of replacement.
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Sassaki, Flávio Tetsuo. "Isolamento e caracterização de promotores órgão-específicos a partir de informações do Banco FORESTs (Eucalyptus Genome Sequencing Project Consortium) /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/102711.
Full textAbstract:
Orientador: Ivan de Godoy MaiaBanca: Luis Eduardo Aranha Camargo
Banca: Adriane Pinto Wasko
Banca: Edson Seizo Mori
Banca: Esteban Roberto González
Resumo: Os cassetes de expressão empregados atualmente para a produção de plantas geneticamente modificadas são baseados, na sua maioria, em promotores constitutivos que determinam a expressão generalizada do transgene na planta, o que muitas vezes não é necessário nem desejado. A alternativa mais viável para substituição de tais promotores é investir na identificação e caracterização de promotores órgão/tecidoespecíficos ou estímulo-dependentes nas espécies de interesse. O presente projeto teve como objetivos identificar e caracterizar genes com padrão de expressão órgãoespecífico em eucalipto e, a partir dessas informações, isolar e caracterizar as seqüências promotoras adjacentes. Predições in silico no banco de dados do projeto de seqüências expressas do eucalipto (FORESTs), e informações disponíveis na literatura a respeito de genes com padrão de expressão órgão-específico, foram utilizadas na seleção. Assim, 59 genes preditos como possuindo expressão exclusiva em dado órgão foram selecionados para a validação via RT-PCR. Dos candidatos validados, 2 eram de raiz, 1 de folha, 1 de botão floral e 1 de botão floral e fruto, concomitantemente. Três candidatos ubíquos também foram selecionados. Dois desses candidatos tiveram seus perfis de expressão em diferentes órgãos de eucalipto avaliados por PCR quantitativa, indicando que o primeiro é preferencialmente expresso em folhas, e o segundo expresso especificamente em raiz. A partir de estratégias de "genome walking" foram isolados diferentes promotores putativos, sendo que o promotor do candidato com expressão preferencial em folha (1.2 kb) foi selecionado para a caracterização funcional em plantas usando o gene uidA, que codifica a -glucuronidase (GUS), como repórter. Em plântulas transgênicas de tabaco da geração T1, a expressão de GUS foi detectada majoritariamente... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Many plant genetic engineering applications require spatial expression of transgenes, which in turn depends upon the availability of tissue- and organ-specific promoters. In the present work, the identification of genes with organ-specific expression in Eucalyptus grandis was performed aiming the subsequent isolation and characterization of contiguous promoter sequences. Candidates genes were selected by in silico predictions in the Eucalyptus EST project (FORESTs) database or by searching the available literature for genes with specific expression patterns. Fifty-nine genes with predicted organ-specific expression were selected for further RT-PCR validation. Among the validated candidate genes, 2 were root-specific, 1 was leaf-specific, 1 was flower-bud-specific and 1 was flower-bud and fruit specific. Three genes ubiquitously expressed were also selected. The relative expression levels of two of them (one leafspecific and one root-specific) over a broad range of eucalyptus organ/tissues were determined using real time PCR. The 5' putative regulatory sequences of the validated genes were isolated using genome walking strategies, and the activity of the leafspecific promoter (1.2 kb) was further investigated in transgenic tobacco plants using a GUS reporter system. In transgenic seedlings from the T1 generation, GUS expression driven by this promoter was detected preferentially in cotyledons. In adult plants, however, GUS expression was detected in both stem and root, but in lower intensity if compared to the expression observed in leaves. This promoter was also able to modulate the transient expression of GUS in seedlings of Eucalyptus grandis.
Doutor
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Salgado, Tiago Pereira. "Efeito do Glyphosate no crescimento, produção e qualidade da madeira do eucalipto (Eucalyptus grandis x E. urophylla) /." Jaboticabal : [s.n.], 2010. http://hdl.handle.net/11449/105315.
Full textAbstract:
Orientador: Pedro Luis da Costa Aguiar AlvesBanca: Edivaldo Domingues Velini
Banca: Pedro Jacob Christoffoleti
Banca: Rinaldo César de Paula
Banca: Roberto Estevão Bragion de Toledo
Resumo: O estudo foi realizado em duas etapas distintas. A primeira, composta por quatro ensaios, constou da aplicação de glyphosate (360 g e.a.L-1) em eucalipto. Em todos os ensaios, mudas foram transplantadas em vasos de 5,0 L. Nos ensaios 1 e 2, foram aplicados volumes de glyphosate no caule do eucalipto. No primeiro ensaio, uma solução de glyphosate na concentração de 3% (v/v) foi aplicada nas doses: 0, 1, 5, 10, 20, 40, 80 e 160 L.planta-1 e, no segundo, a solução a 2% (v/v) foi aplicada nas doses de: 0, 1, 5, 15, 30, 60, 90, 120 e 150 L.planta-1. Nos ensaios 3 e 4, foram feitas aplicações de glyphosate sobre o eucalipto. No ensaio 3 as doses foram: 0, 7,2.10-7, 7,2.10-6, 7,2.10-5, 7,2.10-4, 7,2.10-3, 7,2.10-2, 7,2.10-1, 7,2, 72, 360 e 720 g e.a de glyphosate.ha-1 e, no ensaio 4, as doses foram: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1080, 1440 e 2160 g e.a de glyphosate.ha-1. Nos quatro ensaios foi utilizado o delineamento DIC, com três repetições. Nas plantas foram avaliadas: altura, área foliar, matéria seca de caule e folhas. Os resultados obtidos foram submetidos a análises de regressao. Na segunda etapa, conduzida em campo, o mesmo clone de eucalipto foi plantado em 02/04/2004. Aos 1, 3, 5, 7 e 9 meses após o plantio (MAP), doses 0, 36, 72, 144, 288, 432 g e.a.ha-1 de glyphosate foram aplicadas sobre as plantas. O experimento foi montado em faixas de épocas de aplicação e doses do herbicida. As faixas tinham duas linhas de eucalipto por noventa metros, totalizando 90 plantas. Aos 10, 13, 26, 48 e 62 MAP foram feitas avaliações de altura e diâmetro. Com essas variáveis calculou-se o volume cilíndrico de madeira com casca. Ao final do ensaio (68 meses) foram feitas análises químicas de extrativos, lignina total, holoceluse e densidade basica da madeira nas doses de glyphosate aplicadas aos 5 MAP. Também foi avaliado o rendimento ao cozimento todas as épocas... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The study was conducted in two phase. The first, composed of four trials, consisted of the application of glyphosate (360 g a.e.L-1) on eucalyptus. In all the tests, seedlings were transplanted to pots of 5.0 L. In trials 1 and 2, it was applied volumes of glyphosate on the eucalyptus stem. In the first test, a glyphosate solution at 3% (v/v) concentration was applied in the. doses: 0, 1, 5, 10, 20, 40, 80 and 160 4.plant-1 and, in the second, the solution at 2% (v/v) was applied in the doses of: 0, 1, 5, 15, 30, 60, 90, 120 and 150 viL.plant-1. In the trials 3 and 4, it was made applications of glyphosate on eucalyptus. In the trial 3 doses were 0, 7,2.10-7, 7,2.10-6, 7,2.10-5, 7,2.10-a, 7,2.10-3, 7,2.10-2, 7,2.10-1, 7,2, 72, 360 e 720 g a.e of glyphosate.ha-1 and, in trial 4, the doses were: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1080, 1440 and 2160 g e.a of glyphosate.ha-1. In the fourth tests it was used the randomized completely design, with three replicates. Plants were evaluated by height, leaf area, dry matter of stem and leaves. The results obtained were submitted to regression analyzes. In the second stage, conducted in the field, the same eucalyptus clone was planted in 04-02-2004. At 1, 3, 5, 7 and 9 months after planting (MAP), doses 0, 36, 72, 144, 288, 432 g e.a.ha-1 of glyphosate were applied on the plants. The experiment was installed in strip tests of varying herbicide doses. The strips had two lines of eucalyptus by ninety meters, total of 90 plants. At 10, 13, 26, 48 and 62 MAP assessments were held in height and diameter. With these variables it was calculated the wood volume with bark. At the end of the trial (68 months) it was performed chemical analysis of extractives, lignin total holoceluse and basic wood density at doses of glyphosate applied at 5 MAP. It was also evaluated the wood cooking, in all times of application and doses of glyphosate... (Complete abstract click electronic access below)
Doutor
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Sassaki, Flávio Tetsuo [UNESP]. "Isolamento e caracterização de promotores órgão-específicos a partir de informações do Banco FORESTs (Eucalyptus Genome Sequencing Project Consortium)." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/102711.
Full textAbstract:
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Os cassetes de expressão empregados atualmente para a produção de plantas geneticamente modificadas são baseados, na sua maioria, em promotores constitutivos que determinam a expressão generalizada do transgene na planta, o que muitas vezes não é necessário nem desejado. A alternativa mais viável para substituição de tais promotores é investir na identificação e caracterização de promotores órgão/tecidoespecíficos ou estímulo-dependentes nas espécies de interesse. O presente projeto teve como objetivos identificar e caracterizar genes com padrão de expressão órgãoespecífico em eucalipto e, a partir dessas informações, isolar e caracterizar as seqüências promotoras adjacentes. Predições in silico no banco de dados do projeto de seqüências expressas do eucalipto (FORESTs), e informações disponíveis na literatura a respeito de genes com padrão de expressão órgão-específico, foram utilizadas na seleção. Assim, 59 genes preditos como possuindo expressão exclusiva em dado órgão foram selecionados para a validação via RT-PCR. Dos candidatos validados, 2 eram de raiz, 1 de folha, 1 de botão floral e 1 de botão floral e fruto, concomitantemente. Três candidatos ubíquos também foram selecionados. Dois desses candidatos tiveram seus perfis de expressão em diferentes órgãos de eucalipto avaliados por PCR quantitativa, indicando que o primeiro é preferencialmente expresso em folhas, e o segundo expresso especificamente em raiz. A partir de estratégias de “genome walking” foram isolados diferentes promotores putativos, sendo que o promotor do candidato com expressão preferencial em folha (1.2 kb) foi selecionado para a caracterização funcional em plantas usando o gene uidA, que codifica a -glucuronidase (GUS), como repórter. Em plântulas transgênicas de tabaco da geração T1, a expressão de GUS foi detectada majoritariamente...
Many plant genetic engineering applications require spatial expression of transgenes, which in turn depends upon the availability of tissue- and organ-specific promoters. In the present work, the identification of genes with organ-specific expression in Eucalyptus grandis was performed aiming the subsequent isolation and characterization of contiguous promoter sequences. Candidates genes were selected by in silico predictions in the Eucalyptus EST project (FORESTs) database or by searching the available literature for genes with specific expression patterns. Fifty-nine genes with predicted organ-specific expression were selected for further RT-PCR validation. Among the validated candidate genes, 2 were root-specific, 1 was leaf-specific, 1 was flower-bud-specific and 1 was flower-bud and fruit specific. Three genes ubiquitously expressed were also selected. The relative expression levels of two of them (one leafspecific and one root-specific) over a broad range of eucalyptus organ/tissues were determined using real time PCR. The 5’ putative regulatory sequences of the validated genes were isolated using genome walking strategies, and the activity of the leafspecific promoter (1.2 kb) was further investigated in transgenic tobacco plants using a GUS reporter system. In transgenic seedlings from the T1 generation, GUS expression driven by this promoter was detected preferentially in cotyledons. In adult plants, however, GUS expression was detected in both stem and root, but in lower intensity if compared to the expression observed in leaves. This promoter was also able to modulate the transient expression of GUS in seedlings of Eucalyptus grandis.
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Shrestha, Hari Ram. "Post-fire recovery of carbon and nitrogen in sub-alpine soils of South-eastern Australia /." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/6963.
Full textAbstract:
The forests of south-eastern Australia, having evolved in one of the most fire-prone environments in the world, are characterized by many adaptations to recovery following burning. Thus forest ecosystems are characterized by rapid regenerative capacity, from either seed or re-sprouting, and mechanisms to recover nutrients volatilized, including an abundance of N2 fixing plants in natural assemblages. Soil physical, chemical and biological properties are directly altered during fire due to heating and oxidation of soil organic matter, and after fire due to changes in heat, light and moisture inputs. In natural ecosystems, carbon (C) and nitrogen (N) lost from soil due to fires are recovered through photosynthesis and biological N2 fixation (BNF) by regenerating vegetation and soil microbes.This study investigated post-fire recovery of soil C and N in four structurally different sub-alpine plant communities (grassland, heathland, Snowgum and Alpine ash) of south-eastern Australia which were extensively burnt by landscape-scale fires in 2003. The amount and isotopic concentration of C and N in soils to a depth of 20 cm from Alpine ash forest were assessed five years after fire in 2008 and results were integrated with measurements taken immediately prior to burning (2002) and annually afterwards.
Because the historical data set, comprised of three soil samplings over the years 2002 to 2005, consisted of soil total C and N values which were determined as an adjunct to 13C and 15N isotopic studies, it was necessary to establish the accuracy of these IRMS-derived measurements prior to further analysis of the dataset. Two well-established and robust methods for determining soil C (total C by LECO and oxidizable C by the Walkley-Black method) were compared with the IRMS total C measurement in a one-off sampling to establish equivalence prior to assembling a time-course change in soil C from immediately pre-fire to five years post-fire. The LECO and IRMS dry combustion measurements were essentially the same (r2 >0.99), while soil oxidizable C recovery by the Walkley-Black method (wet digestion) was 68% compared to the LECO/IRMS measurements of total C. Thus the total C measurement derived from the much smaller sample size (approximately 15 mg) combusted during IRMS are equivalent to LECO measurement which require about 150 mg of sample.
Both total C and N in the soil of Alpine ash forests were significantly higher than soils from Snowgum, heathland and grassland communities. The ratio of soil NH4+ to NO3- concentration was greater for Alpine ash forest and Snow gum woodland but both N-fractions were similar for heathland and grassland soils. The abundance of soil 15N and 13C was significantly depleted in Alpine ash but both isotopes were enriched in the heathland compared to the other ecosystems. Abundance of both 15N and 13C increased with soil depth.
The natural abundance of 15N and 13C in the foliage of a subset of non-N2 fixing and N2 fixing plants was measured as a guide to estimate BNF inputs. Foliage N concentration was significantly greater in N2 fixers than non-N2 fixers while C content and 13C abundance were similar in both functional groups. Abundance of 15N was depleted in the N2 fixing species but was not significantly different from the non-N2 fixers to confidently calculate BNF inputs based on the 15N abundance in the leaves.
The total C pool in soil (to 20 cm depth) had not yet returned to the pre-fire levels in 2008 and it was estimated that such levels of C would be reached in another 6-7 years (about 12 years after the fire). The C and N of soil organic matter were significantly enriched in 15N and 13C isotopes after fire and had not returned to the pre-fire levels five years after the fire. It is concluded that the soil organic N pool can recover faster than the total C pool after the fire in the Alpine ash forests.
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Carneiro, Paulo Henrique Marostegan e. "Caracterização florística, estrutural e da dinâmica da regeneração de espécies nativas em um povoamento comercial de Eucalyptus grandis em Itatinga, SP." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11142/tde-22082002-152108/.
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Os objetivos deste trabalho foram analisar a composição florística, a estrutura, alguns aspectos da dinâmica da regeneração de espécies nativas no sub-bosque de povoamentos comerciais de Eucalyptus spp e estudar o impacto que algumas práticas silviculturais (desbaste e corte raso) sobre a regeneração. Para isso, foram locadas 17 parcelas (0,68 ha de área amostral) em um talhão de Eucalyptus grandis (Talhão 48), na Fazenda São José do Bromado, coordenadas geográficas 23°1330S e 48°3407W, município de Itatinga SP. Na avalia ção da composição e estrutura da regeneração, realizada 30 meses após o corte da primeira rotação do povoamento de eucalipto, foram plaqueados e identificados todos os indivíduos arbóreos ou arbustivos com altura superior a 1,5m. O estudo da evolução temporal da regeneração foi realizado em 2 avaliações, 30 e 45 meses após a exploração do povoamento de eucalipto, utilizando o mesmo método de análise, sendo considerado morto o indivíduo amostrado nos levantamento anterior e não localizado na avaliação seguinte. Após a segunda avaliação as parcelas foram divididas em três tratamentos, sendo: Tratamento 1 testemunha (área amostral de 0,2ha), no qual o povoamento de eucalipto foi mantido, Tratamento 2 (área amostral de 0,24ha) no qual foi realizado o desbaste de 50% do povoamento de eucalipto e Tratamento 3 (área amostral de 0,24ha) no qual foi realizado o corte raso do eucalipto. Após a implantação dos tratamentos (46 meses após a exploração do povoamento) foram realizadas duas avaliações, a primeira 54 meses e a segunda 61 meses após a exploração da primeira rotação do povoamento de E. grandis. Foram amostrados 1900 indivíduos (104 espécies e 38 famílias) na primeira avaliação. A família de maior riqueza florística foi Myrtaceae seguida de Asteraceae, Fabaceae e Solanaceae, sendo esta última a que apresentou a maior densidade de indivíduos. As espécies de maior densidade relativa foram Solanum variabile e Matayba elaeagnoides. 76,66% dos indivíduos amostrados pertenciam a famílias que apresentaram padrão de distribuição espacial agregado. Na avaliação da dinâmica da regeneração, constatou-se que o recrutamento de novos indivíduos no sub-bosque do eucalipto no período de 30-45 meses da exploração comercial se concentrou nos grupos de espécies secundárias iniciais, secundárias tardias e espécies típicas da condição de sub-bosque. Enquanto a mortalidade se concentrou nos indivíduos pertencentes ao grupo das espécies pioneiras e das espécies não classificadas sucessionalmente. No período o índice para diversidade de Shannon (H´), apresentou crescimento de 3,48 para 3,573, e a equabilidade (J), crescimento de 0,751 para 0,762, mostrando que houve ganho em relação a diversidade de espécies na área. No estudo do impacto que diferentes práticas silviculturais impõem a regeneração, o tratamento 1 testemunha foi o que apresentou as menores taxas de mortalidade e o maior ingresso de espécies no período analisado. As operações de corte e remoção causaram grande impacto nos tratamentos 2 desbaste de 50% do povoamento de E. grandis e tratamento 3 corte raso, aumentando a taxa de mortalidade e diminuindo a taxa de recrutamento de indivíduos na regeneração. O Tratamento 2 foi o único a apresentar ganhos em diversidade (H) em todos os levantamentos.The objectives of this study were to analyze a floristic composition, the structure, some aspects of the dynamics of regeneration of native species in understory of commercial stands of Eucalyptus spp and to study the impact that some silvicultural practices (thinning and clear cut) have on regeneration. For this purpose, 17 samples (0.68 ha total sample area) were located in a stand of Eucalyptus grandis (Stand 48), on the São José do Bromado Farm, geographical coordinates 23°1330S and 48°3407W, municipal of Itatinga, Sao Paulo. In the evaluation of the composition and structure of the regeneration, done 30 months after the clear cut of the first rotation of Eucalyptus grandis, all of the individual trees up to 1.5m of height were tagged and identified. The study of the temporal evolution of regeneration was done in 2 evaluations, 30 and 45 months after the clear cut of the stand. The same method of analysis was used, being that the individual trees measured previously and not found in the second evaluation were considered dead. After the second evaluation the samples were divided into three treatments: Treatment 1- control (sample area of 0.2ha), of which the trees were maintained, Treatment 2 (sample area of 0.24ha), of which 50% thinning was done, and Treatment 3 (sample area of 0.24ha), of which clear cut was done. After the implementation of the treatments (46 months after the exploration), two evaluations were accomplished. The first at 54 months and the second at 61 months, after the exploration of the first rotation of the stand. One thousand nine hundred trees (104 species and 38 families) were sampled in the first evaluation. The largest floristic family verified was Myrtaceae followed by Asteraceae, Fabaceae and Solanaceae, the family which presented the largest density of individuals. Whereas the species with the greatest relative density were Solanum variabile and Matayba elaeagnoides. Among the individual samples, 76.66% were of the families that present a pattern of aggregate spatial distribution. In evaluating the dynamics of regeneration, it was found that the recruitment of new individuals in understory of eucalyptus during the period of 30-45 months after the commercial exploration was focused on the groups of initial secondary species, late secondary and typical species of understory. The mortality was concentrated in the group of pioneer species and non-classified species, respectively. The index period to the Shannon diversity (H), presented growth of 3.48 to 3.573, and eqüability (J), growth of 0.751 to 0.762, showing to have gained in relation to the diversity of species of the area. The study of the impact that different silvicultural practices have on regeneration, treatment 1- presented the least incidence of mortality and the greatest incidence of species during the analysis period. The practices of thinning and clear cut caused a great impact on treatments 2 and 3, improving the incidence of mortality and decreasing the incidence of new individuals of regeneration. Treatment 2 was the only one to present gains in diversity (H) in all of the evaluations.
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Zonete, Maria Carolina Cunha. "Avaliação do uso de técnicas de interpolação para estimativa de volume em florestas clonais de Eucalyptus sp." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-05082009-082221/.
Full textAbstract:
O conhecimento do estoque florestal é uma importante ferramenta para que o planejamento de curto, médio e longo prazo possam ser realizados. Em cada talhão o estoque é obtido através do inventário florestal. O trabalho realizado teve como objetivo aplicar conceitos de geoestatística que se beneficiem da dependência espacial de certas variáveis para estimar o volume em pontos não amostrados. Para a realização deste estudo, foram utilizados métodos de interpolação, procedimento pelo qual se estimam valores de uma variável em área interior aos pontos de amostragem disponíveis, permitindo representar o comportamento de variáveis amostradas pontualmente e extrapolar valores da variável fora dos limites da área amostrada. Foram instaladas 34 parcelas para estimativa do inventário florestal e 36 parcelas de controle para comparar as diferenças entre o valor estimado e o valor efetivamente medido das variáveis: volume, área basal e altura média de um povoamento de clones de eucalipto em aproximadamente 205 ha, localizados em Mogi-Guaçu-SP. Além destas parcelas, foram mensuradas 24 parcelas em uma área vizinha aos talhões em estudo para compor cenários que pudessem melhorar a estimativa em regiões de borda. Com o auxílio do software Geomedia Professional®, três métodos de interpolação foram testados: Krigagem universal, Inverso da distância ponderada (IDW) e Spline. Para cada um dos métodos foram realizadas simulações com a inclusão de novas parcelas visando avaliar o comportamento da estimativa com o aumento da intensidade amostral. Nesse procedimento, foram criados 6 diferentes cenários com crescente números de parcelas: Am com 34 parcelas; G com 58 parcelas; G+5 com 63 parcelas; G+10 com 68 parcelas; G+15 com 73 parcelas e G+20.com 78 parcelas. A comparação entre o valor estimado e valor medido foi feita através dos erros em porcentagem para cada parcela. Todos os modelos testados apresentaram uma tendência, em média, a subestimar os valores. O erro mínimo encontrado para volume foi de -3,17% estimado pelo modelo Spline. Para altura média e área Basal os menores desvios foram de -1,7% e 0,82% igualmente estimados pelo modelo Spline. Na estimativa realizada através do modelo Krigagem, o melhor resultado foi de - 7,95%, -2,25% e -5,75% de desvio para área basal, altura e volume, respectivamente. Já o modelo IDW resultou num desvio de -7,48%, -1,29%, 7,53% para as mesmas variáveis. A análise dos resultados mostra que a estimativa por meio de interpolação utilizando modelos implícitos em software geoestatísticos produz alguns desvios significativos e o uso de modelos geoestatísticos ajustados ao conjunto de dados pode produzir estimativas melhores.The Knowledge about the forest stock is an important tool to support the short, medium and long term planning. In each stand the stock is obtained through the forest inventory. This work aimed to apply geostatistics concepts that get benefits from the spatial dependence of certain variables to estimate the volume at non sampled points. For this study, it were used interpolation methods ,which procedure is used to estimate the variables values in the internal area of the sampled points, allowing to represent the locally sampled variables behavior and extrapolate the variables value to the outside sampled area. It were sampled 34 plots to estimates the forest inventory and 36 control plots were sampled to compare the differences between the estimated and actually measured value for the variables: volume, basal area and average height of a cloned Eucalyptus group of stands in approximately 205 ha, located in Mogi-Guaçu-SP. Futher these plots, it were measure more 24 plots in an adjacent area which were used to compose a scenarios study that could support the improvements in borders regions estimations. Using the Geomedia Professional ® software, three interpolation methods were tested: Kriging, Inverse Distance Weighting (IDW) and Spline. For each method it was performed simulations considering the inclusion of new plots to evaluate the estimate behavior by increasing the sample size. In this procedure, we created 6 different scenarios with increasing numbers of plots: Am with 34 plots, G with 58 plots, G +5 with 63 plots, G +10 with 68 plots, G +15 with 73 plots and G +20 with 78 plots. The comparison between the estimated and measured value was made through the errors in percentage for each plot. All the tested models had a tendency, on average, to underestimate the values. The minimum error found for volume was -3.17% estimated by the Spline model. For height and basal area the minor deviations were -1.7% and 0.82% estimated by the Spline model also. In the estimations made by the Kriging model, the best result was -7.95%, -2.25% and -5.75% deviation for basal area, height and volume, respectively. IDW model resulted in a deviation of -7.48%, -1.29%, -7.53% for the same variables. The result analysis shows that the estimations made by the interpolation models using implicit geostatistical software models produces some significant deviations and the use of adjusted geostatistical models to the data set may produce better estimates.
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Vieira, Eduardo Henrique de Freitas. "Produção de biomassa de Eucalyptus spp. sob diferentes manejos e espaçamentos." Universidade Federal do Espírito Santo, 2011. http://repositorio.ufes.br/handle/10/5772.
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Previous issue date: 2011-06-29This study aimed to evaluate the biomass production, height and DBH of eucalyptus on two management regimes: rainfed and fertigated, three genetic materials and six different spacings, in the state of Espírito Santo. The design adopted was randomized blocks, with repetition. It was observed that, in general, the major growth and productivity of biomass occurred in the regime fertigated. We also observed, higher yields in the early ages for the dense spacing, however, with increasing age, the larger distance remained more uniform and exceeded the productivity of smaller spaces. Biomass production varied depending on the genetic material, plant spacing and irrigation. The treatment using the genetic material AR4 had productivity of 60 t/ha/year at 12 months of age in the management and spacing fertigated 3x1 and 3x2 m. For the clonal materials showed major biomass production (55 t/ha/year) in the interaction of management fertigated spaced 3x2 m at 12 months old. Genetic material in 1501 produced 45 t/ha/year in the 3x1 m spacing at 12 months of age. The genetic material in 3918, and interaction management fertigated 3x1 and 3x2 m spacings, produced at 12 months of age, 45 t/ha/year. Evaluating only the 1x1 m spacing (super dense) with the seminal genetic material in dryland management, we observed the production of 55 t/ha/year, at 12 months. Considering a spacing of 1x1 and 2x1 m (extreme cases), the mortality due to competition between plants is so high that at the end of two years, the number of live plants was reduced to approximately 30%. If we consider the additional costs of drip irrigation and planting density, compared to traditional management culture (3x3 m spacing in dry), it is important to evaluate the economic viability of this type of strategy for biomass energy production
Esta pesquisa objetivou avaliar a produção de biomassa, a altura e o DAP de eucalipto sobre dois regimes de manejos: fertirrigado e sequeiro, três materiais genéticos e seis espaçamentos diferentes, no estado do Espírito Santo. O delineamento adotado foi em blocos ao acaso, com repetição. Observou-se, em geral, que o maior crescimento e produtividade de biomassa ocorreram no regime fertirrigado. Foi observado, ainda, maiores produtividades nas idades iniciais para os espaçamentos mais adensados, entretanto, com o aumento da idade, os espaçamentos maiores se mantiveram mais uniformes e superaram a produtividade dos espaçamentos menores. A produção de biomassa variou em função do material genético, do espaçamento de plantio e do manejo de irrigação. O tratamento utilizando o material genético AR4 teve produtividade de 60 t/ha/ano aos 12 meses de idade no manejo fertirrigado e espaçamentos 3x1 e 3x2 m. Para os materiais clonais observou-se maior produção de biomassa (55 t/ha/ano) na interação do manejo fertirrigado com espaçamento 3x2 m, aos 12 meses de idade. O material genético 1501 produziu 45 t/ha/ano no espaçamento 3x1 m aos 12 meses de idade. O material genético 3918 na interação manejo fertirrigado e espaçamentos 3x1 e 3x2 m, produziu aos 12 meses de idade, 45 t/ha/ano. Avaliando apenas o espaçamento 1x1m (super adensado) com o material genético seminal, no manejo sequeiro, observou-se a produção de 55 t/ha/ano, aos 12 meses. Considerando um espaçamento de 1x1 e 2x1 m (casos mais extremos), a mortalidade devido à competição entre as plantas é tão alta que, ao final de dois anos, o número de plantas vivas se reduziu para aproximadamente 30%. Se forem considerados os custos adicionais de fertirrigação e de adensamento do plantio, em relação ao manejo tradicional da cultura (espaçamento 3x3 m em sequeiro), é importante avaliar a viabilidade econômica deste tipo de estratégia para fins de produção de biomassa energética
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De, Remy De Courcelles Vivien. "Studies of soil respiration in eucalypt forests of south east Australia." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/10422.
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This thesis addresses gaps in knowledge of soil respiration in forests of south-east Australia. Soil respiration plays a major part in the cycle of carbon between soils - the biggest pool of terrestrial carbon - and the atmosphere. Despite its global significance, we have only a limited understanding of the magnitude and responses of soil respiration, and especially of its components, to abiotic (temperature, moisture, soil fertility) and biotic (photosynthesis, seasonality of belowground C allocation patterns and root growth, quality and quantity of above and belowground litter) controls. Furthermore, vegetation type may modulate the influences of these abiotic and biotic controls and with soil respiration research having been based mostly in the northern hemisphere, it is crucial that regional studies be conducted further afield. This thesis also considers the context of the current increase in atmospheric [CO2] and resulting predicted climate change that will directly or indirectly impact on soil respiration through extreme weather events, changes in the frequency and intensity of fires or increase in growth. Using both field and laboratory based techniques I measured respiration from soils supporting a variety of Eucalypts. Elevated atmospheric [CO2] did not have an effect on rates of soil respiration in a Eucalyptus saligna plantation, contrary to usual findings. Drought on the other hand slowed rates of respiration, owing to a slowing of the transfer of photosynthates from leaves to roots. The impact of an increase in above-ground litter deposition, a possible consequence of extreme weather events, or continuous increase in primary production can be subdued by the nature and quality of the litter in Eucalyptus pauciflora woodlands. No effect was recorded in the field but ground litter added to soils in the laboratory triggered a response including a priming effect. Root priming effect was also found to increase basal heterotrophic respiration by 54% on average in Eucalyptus regnans. The study on the contribution of roots to total soil respiration showed that it is necessary to use hybrid techniques to separate and estimates the contribution of components of soil respiration; in this thesis’ case the use of collars and chambers in the field and respirometer in the laboratory was determinant in identifying root priming effect. Great spatial variation in respiration rates was measured both in the simple ecosystem of a Eucalyptus saligna plantation and as a result of fire disturbance at the Messmate 1 site supporting Eucalyptus obliqua and Eucalyptus radiata. Finally, a synthesis of the results of the whole thesis considered the effect of soil temperature on soil respiration and showed that contrary to what is commonly agreed by the Q10 model, respiration rates reached a plateau for temperatures between 16°C to 23°C.
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Ballinger, Andrea Alleyne. "Influence of habitat variability on macroinvertebrate biodiversity in river red gum Eucalyptus camaldulensis floodplain forest." Monash University, School of Biological Sciences, 2003. http://arrow.monash.edu.au/hdl/1959.1/5768.
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Sá, Ariadne Felício Lopo [UNESP]. "Crescimento de plantas de Corymbia citriodora (Hook.) K. D. Hill & L. A. S. Johnson sob diferentes doses de potássio e níveis de umidade do solo." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/96834.
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000691553.pdf: 387979 bytes, checksum: 7384aa5243d287d150b0baeafef6362a (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O objetivo deste trabalho foi avaliar os efeitos de doses de potássio e níveis de umidade do solo no crescimento de plantas de Corymbia citriodora. Foram aplicadas quatro doses de potássio (0, 40, 80 e 120 mg dm-3) e três níveis de umidade do solo (50-80%, 65-80% e 80% do volume máximo de água retido pelo solo em vaso), combinados em um esquema fatorial 4 x 3. O delineamento experimental foi inteiramente casualizado com seis repetições, e cada parcela foi composta por um vaso contendo duas plantas. Aos 94 dias após o plantio, foram avaliados: porcentagem de sobrevivência, altura, diâmetro do caule, número de folhas, área foliar, massa de matéria seca de folhas, de caule e ramos, da parte aérea, de raízes e total das plantas da parcela, comprimento e diâmetro das raízes, índice de conteúdo de clorofila, concentração de clorofilas, concentração e acúmulo foliar de macronutrientes e eficiência de utilização de potássio nas folhas. O aumento do nível de umidade do solo favoreceu o crescimento das plantas de Corymbia citriodora e a absorção de fósforo, potássio, enxofre e magnésio. A aplicação de potássio não promoveu a amenização dos efeitos negativos da redução da disponibilidade de água no crescimento das plantas
The objective of this work was to evaluate the effects of potassium and soil moisture levels on the growth of Corymbia citriodora plants. Four doses of potassium were applied (0, 40, 80 and 120 mg dm-3) and three soil moisture levels were established (50-80%, 65-80% and 80% of maximum soil field capacity). The experiment was a 4 x 3 factorial arrangement of treatments within a randomized complete design with six replications for each treatment and one pot with two plants for each plot. At 94 days after planting, the plant growth parameters: survival percentage, height, stem diameter, leaf number and area, leaf dry mass, stem and branches dry mass, shoot dry mass, root dry mass, total dry mass, length and diameter of roots, chlorophyll content index, chlorophylls concentrations, leaf macronutrient contents and amounts, and efficiency of potassium utilization by leaves were measured. The increase of soil moisture level benefited the growth of Corymbia citriodora plants and phosphorus, sulfur and magnesium uptake. The potassium application did not promote alleviation of negative effects caused by low water availability on plant growth
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Pereira, Jaqueline Magalhães [UNESP]. "Resistência de genótipos de eucalipto ao psilídeo-de-concha Glycaspis brimblecombei Moore (Hemiptera: psyllidae)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/106634.
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pereira_jm_dr_botfca.pdf: 1295918 bytes, checksum: f68afd1f3561ee4b65e51e0137d4d990 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Desde sua introdução no Brasil, em 2003, o psilídeo-de-concha Glycaspis brimblecombei Moore (Hemiptera: Psyllidae) vem ocasionando sérios danos ao eucalipto, principalmente através de desfolha, desenvolvimento de fumagina e secamento de ponteiros. Como estratégia no controle deste inseto, o uso de genótipos resistentes pode ser uma ferramenta valiosa. Neste trabalho, avaliou-se a resistência das espécies Eucalyptus camaldulensis (VM e IPEF), E. grandis e E. urophylla e dos híbridos de E. grandis x E. camaldulensis – gracam ‘HGC’ (3025 e 1277), de E. urophylla x E. camaldulensis – urocam ‘HUC’ (VM-1), de E. urophylla x E. grandis – urograndis ‘HUG’ (H-13, I-144, C-219 e GG-100) e de E. grandis (EG-01, EG-02 e EG-03) a G. brimblecombei, através de testes de atratividade, preferência para oviposição e preferência para alimentação e/ou antibiose sob condições de laboratório e campo. Foram realizados testes preliminares, a fim de verificar a ocorrência de condicionamento pré-imaginal, além de ajustar a melhor densidade para infestação com adultos para testes de atratividade e a melhor posição nas mudas para avaliações de preferência para oviposição. Em laboratório, verificou-se que os adultos de G. brimblecombei não apresentaram condicionamento pré-imaginal, independentemente do hospedeiro de criação ser o híbrido 3025 ou E. camaldulensis IPEF. As densidades de 10 e 15 adultos de psilídeo-de-concha por muda de eucalipto proporcionaram maior número de ovos. As folhas próximas ao ápice foram preferidas para oviposição, sendo que o número de ovos decresceu do ápice para a base. No teste com chance de escolha, os genótipos E. grandis, E. urophylla, C-219 e H-13 foram menos atrativos ao psilídeo-de-concha, expressando não-preferência. Em teste com chance de escolha, o número de ovos depositados nas folhas dos genótipos H-13, E. grandis...
Since its introduction in Brazil in 2003, the red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psyllidae) has been causing serious damages in eucalyptus trees, especially through defoliation, development of sooty mold and dieback. The use of resistant genotypes as a strategy to control this insect may be a valuable tool. In this study, the resistance of species Eucalyptus camaldulensis (VM e IPEF), E. grandis and E. urophylla and hybrids E. grandis x E. camaldulensis - gracam ‘HGC’ (3025 and 1277), E. urophylla x E. camaldulensis - urocam ‘HUC’ (VM-1), E. urophylla x E. grandis – urograndis ‘HUG’ (H-13, I-144, C-219 and GG-100) and E. grandis (EG-01, EG-02 and EG-03) on G. brimblecombei, through attractiveness, oviposition preference and feeding preference and/or antibiosis tests under laboratory and field conditions evaluated. Initially preliminary tests were carried out, using eucalyptus seedlings, in order to verify the occurrence of preimaginal conditioning, and also adjust the best density for adult infestation for attractiveness tests and the best position in the seedlings for the evaluation of oviposition preference. In laboratory conditions, that G. brimblecombei adults did not present preimaginal conditioning, despite the fact that the rearing host was a 3025 hybrid or E. camaldulensis IPEF. The densities of 10 and 15 psyllid adults per eucalyptus seedlings showed a higher number of eggs. The insects showed preference for the leaves close the apex for oviposition, being that the number of eggs decreased from the apex to the basis. In the choice test concerning attractiveness, genotypes E. grandis, E. urophylla, C-219 and H-13 were less attractive to psyllid, showing non-preference. In a choice test, the number of eggs oviposited in leaves of genotypes H-13, E. grandis and E. urophylla were lower when compared... (Complete abstract click electronic access below)
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Silva, Paula Ventura da. "Emprego de redes neurais artificiais com skip-layer connections na mensura??o florestal." UFVJM, 2015. http://acervo.ufvjm.edu.br/jspui/handle/1/999.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
RESUMO SILVA, Paula Ventura da, M.Sc., Emprego de redes neurais artificiais com Skip-Layer Connections na mensura??o florestal. 2015. 46 f. Disserta??o (Mestrado em Ci?ncia Florestal) ? Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, 2015. O objetivo principal deste estudo foi avaliar a aplica??o de Redes Neurais Artificiais (RNA) utilizando a t?cnica Skip-layer connections, com e sem recorr?ncia, para estima??o do volume individual e da altura total de ?rvores de eucalipto. Os objetivos espec?ficos foram testar e avaliar as redu??es no tamanho da base de dados do conjunto de ajuste (treinamento) para estima??o dessas vari?veis. Os dados utilizados foram provenientes de ?rvores abatidas para cubagem (estima??o do volume individual) e de medi??es de parcelas permanentes de invent?rios florestais cont?nuos (estima??o da altura total), em ?rea de povoamentos de eucalipto localizados no sul da Bahia, Brasil. Foram treinadas redes do tipo Multilayer Perceptron (MLP), utilizando a fun??o de ativa??o log?stica nas camadas intermedi?ria e de sa?da e oito neur?nios na camada oculta. O n?mero de neur?nios na camada de entrada variou conforme o n?mero e o tipo de vari?vel (qualitativa ou quantitativa) em cada estudo. Os crit?rios de parada foram o erro m?dio quadr?tico de 0,0001 ou 3.000 ciclos (?pocas). Em seguida, as RNA selecionadas foram aplicadas em parte dos dados separados, para generaliza??o (valida??o). O software utilizado para o treinamento e a generaliza??o das RNA foi o NeuroForest 3.3. Para compara??o dos resultados obtidos pelas RNA, foram ajustados os modelos tradicionais de regress?o tanto para volume, quanto para altura, e tamb?m foram treinadas e aplicadas RNA usando o algoritmo Resilient Propagation, comumente utilizado em aplica??es da mensura??o florestal. A avalia??o dos resultados gerados pelas RNA e pelos modelos de regress?o foi feita por meio do coeficiente de correla??o entre os valores observados e estimados, de gr?ficos de dispers?o e de histogramas de frequ?ncia percentual dos erros percentuais. As Redes Neurais Artificiais utilizando Skip-layer connections apresentaram resultados satisfat?rios para estima??o de volume e de altura de ?rvores de eucalipto, o que evidencia a possibilidade de aplicar a t?cnica em mensura??o e manejo florestal e uma expressiva redu??o das bases de dados para treinamento das RNA.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015.
ABSTRACT SILVA, Paula Ventura da, M.Sc. Artificial neural networks with skip-layer connections in forest measurement. 2015. 46 f. Dissertation (Master in Forest Science) ? Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, 2015. The aim of this study was to evaluate the application of Artificial Neural Networks (ANN) using the Skip-layer connections technique, with and without recurrence, to estimate the individual volume and total eucalyptus trees height. Its specific objectives were to test and evaluate reduction in the size of the adjustment assembly database (training) for estimating these variables. The data came from trees felled for scaling (estimation of individual volume) and measurements of permanent plots of continuous forest inventories (estimation of the total height), in eucalypt plantation area located in the south of Bahia, Brazil. Multilayer Perceptron (MLP) network type, using the logistic activation function in the intermediate and output layers and eight neurons in the hidden layer, were trained. The neurons number in the input layer varied according to the number and type of the variable (qualitative or quantitative) in each study. The stopping criteria were the root mean square error 0.0001 or 3,000 cycles (seasons). The software used for the RNA training and generalization was the NeuroForest 3.3. To compare the results obtained by RNA, traditional regression models were set for both the volume and the height, as well as RNA were trained and applied using the Resilient Propagation algorithm, commonly used in forest measurement applications. The evaluation of the results generated by the RNA and by the regression models was made via the correlation coefficient between observed and estimated values, scatter plots and histograms percentage frequency of the percentage errors. Artificial Neural Networks using Skip-layer connections showed satisfactory results for the estimation of volume and eucalyptus trees height, demonstrating the possibility of applying the technique in measuring and forest management and a significant reduction of databases for RNA training.
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Smit, Norman Hein. "Weathering behaviour of Colorado (Eucalyptus camaldulensis and Eucalyptus tereticornis) and Balau (Shorea spp.)." Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4202.
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Thesis (MScFor (Forest and Wood Science))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: Balau, a group consisting of 21 Shorea species, is widely used for outdoor application. In South Africa, Balau is one of the most popular materials used for decking. Due to the increasing scarcity of Balau, it is of economic importance to investigate the possibility of a substitute timber for decking material. One possible timber could be Colorado, a mixture containing one or more of the following: Eucalyptus camaldulensis, Eucalyptus tereticornis and their hybrids. These two species and their hybrids are extensively cultivated in countries such as Australia, India and parts of South America because of their short rotation period and easy adaptability to a wide variety of soil and climatic factors. The timber was initially utilized as raw material for the pulp and paper industry but is now gaining importance in structural uses like furniture, flooring and decking. The aim of this exploratory study was to investigate relevant material properties and to examine the natural and accelerated weathering behaviour of Colorado and Balau to predict Colorado’s suitability as decking material. It was found that Colorado had smaller vessel lumina, fewer vessels/m2 and smaller rays than Balau and had a higher density than Balau. Although both timbers had a relatively low FSP, Colorado’s FSP was 2.3 percentage points higher than Balau’s. The swelling coefficients (radial and tangential) of Colorado were slightly higher than Balau’s but Colorado’s lower swelling anisotropy can result in a lower tendency to twist in service. Colorado had a higher water soluble extractive content than Balau, which can lead to the rapid initial colour changes when the timber is exposed uncoated. The weathering performance of Colorado and Balau was investigated by exposing samples in a QUV accelerated weathering apparatus and to natural weathering at an inland and a marine location. During weathering Colorado showed a slightly higher colour change ( E*) than Balau. Balau showed a higher increase in roughness (Rz), surface checking and check formation than Colorado. Colorado showed slightly more cup than Balau, however, Balau showed much larger amounts of twisting than Colorado. No statistically significant differences were found between the hydrophobicity of the two timbers. A coating was effective in increasing the initial hydrophobicity of samples and could maintain a relatively hydrophobic surface during weathering. No statistically significant differences were found in the effect of sample cut on timber species surface wettability. Although only long term exposure studies and using substantially more samples can confirm its weathering performance, the results of this exploratory weathering study indicated that Colorado can successfully be used as a substitute decking material for Balau.
AFRIKAANSE OPSOMMING: Balau, ‘n houtsoort wat ongeveer 21 Shorea-spesies verteenwoordig, word wyd in buitenshuise aanwendings benut. In Suid-Afrika is Balau een van die mees gewilde materiale wat vir dek-doeleindes gebruik word. As gevolg van die toenemende skaarsheid van Balau, is dit van ekonomiese belang om die gebruik van ‘n moontlik plaasvervangende houtsoort vir dek-materiaal te ondersoek. Colorado, ‘n mengsel van een of meer van die volgende: Eucalyptus camaldulensis, Eucalyptus tereticornis en hibriede daarvan, kan as ‘n moontlike plaasvervanger gebruik word. Hierdie twee spesies en hulle hibriede word op groot skaal in lande soos Australië, Indië en dele van Suid-Amerika gekweek vanweë hul kort rotasieperiode en goeie aanpasbaarheid by ‘n wye verskeidenheid grond- en klimaatsfaktore. Die spesies is aanvanklik as grondstof in die pulp- en papierbedryf gebruik maar word tans al hoe belangriker in strukturele aanwendings soos byv. meubels, vloer- en dek-materiaal. Die doel van hierdie verkennende studie was om relevante materiaaleienskappe te ondersoek en om die versnelde en natuurlike verweringsgedrag van Colorado en Balau vas te stel om sodoende ‘n aanduiding van die geskiktheid van Colorado as dek-materiaal te kan kry. Daar is gevind dat Colorado kleiner vat-lumina, minder vate/m2 en kleiner strale as Balau besit en dat Colorado ‘n hoër digtheid het as Balau. Alhoewel beide houtsoorte relatiewe lae veselversadigingspunte (VVP) besit, is Colorado se VVP 2.3% persentasiepunte hoër as dié van Balau. Die swellingskoëffisiente (radiaal en tangensiaal) van Colorado is effens hoër as dié van Balau, maar Colorado se laer swellingsanisotropie kan op ‘n kleiner neiging tot skeeftrek dui. Colorado het ‘n hoër wateroplosbare ekstrakstofinhoud as Balau bevat, wat tot aanvanklik vinnige kleurveranderings kan lei wanneer die hout sonder oppervlaktemiddel blootgestel word. Die verweringsgedrag van Colorado en Balau is ondersoek deur monsters aan versnelde en natuurlike verwering bloot te stel. Eersgenoemde is in ‘n QUV versnelde verweringsapparaat uitgevoer en laasgenoemde in ‘n binnelandse en ‘n mariene lokaliteit. Tydens verwering het Colorado ‘n effens hoër kleurverandering ( E*) as Balau getoon. Balau het ‘n hoër toename in rofheid (Rz), oppervlaktekrake en kraakvorming as Colorado getoon. Colorado het effens meer kromgetrek terwyl Balau meer skeefgetrek het as Colorado. Geen statisties beduidende verskille kon tussen die waterwerende eienskappe van die twee houtsoorte vasgestel word nie. ‘n Oppervlakbedekking was effektief om die aanvanklike toename in waterwerende vermoë te verhoog en gedurende verwering te kon behou. Geen statisties beduidende verskille kon tussen die invloed van snit van die monster op die oppervlaktebenatbaarheid van die houtsoorte vasgestel word nie. Alhoewel slegs langtermyn blootstellingstudies en die gebruik van beduidend veel meer monsters die verweringsgedrag kan bevestig, dui die resultate van hierdie verkennende ondersoek aan dat Colorado suksesvol as ‘n plaasvervangende dekmateriaal vir Balau gebruik kan word.
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Burgar, Joanna. "Bat habitat use of restored jarrah eucalypt forests in south-western Australia." Thesis, Burgar, Joanna (2014) Bat habitat use of restored jarrah eucalypt forests in south-western Australia. PhD thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/24229/.
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Restoration is an important tool in conserving biodiversity, yet passive faunal recolonisation may take decades, or longer, to occur. This is of particular conservation importance in biodiversity hotspots, such as south@western Australia, which are experiencing increasing fragmentation and rapidly drying climates. Within this hotspot, I investigated the response of nine insectivorous tree@dwelling bat species to restored mine@pits in jarrah (Eucalyptus marginata) forests. I assessed bat activity in restored, relative to unmined, forests and the suitability of restoration as foraging and roosting habitat. Bat echolocation call surveys measured bat activity in varying ages of restoration and unmined forest across two years (2010@2012) during both maternity and mating seasons. Although all bat species were detected in both forest types, restored mine@pits of all ages had significantly different bat communities and lower overall activity compared to unmined forest. Habitat filters to bat use of restoration were evident for the more manoeuvrable bat species and were predominantly related to midstorey forest structure. Tree density was the most important predictor of bat use of restoration for less manoeuvrable bat species. To determine the suitability of restored forest as foraging habitat I investigated the diet of three species (Chalinolobus gouldii, Nyctophilus gouldi and Vespadelus regulus) over maternity and mating seasons (2010/2011) by examining prey remains in faecal samples. I used high@throughput sequencing and bioinformatics analyses to phylogenetically group prey DNA and found that niche partitioning occurred, with dietary divergence positively related to bat ecomorphological divergence. In addition, I assessed the foraging potential of restored forest and found that prey occurrence did not necessarily equate to prey accessibility for all bat species. There was a synergistic effect of vegetation structure and insect biomass for edge foraging bat species. To determine the suitability of restoration as roosting habitat I used telemetry to radio@track 36 bats from two species (N. gouldi and V. regulus) to 59 distinct roosts. Not one bat was found roosting in restored forest and individuals preferred roosting in mature, tall trees in intermediate to late stages of decay. My research clearly shows that restored forest does not yet provide suitable foraging or roosting habitat for all jarrah forest bats. Improving habitat suitability through management manipulations, such as thinning and burning, may accelerate bat recolonisation of restored forest. In the interim, retention of mature forest patches is necessary for conserving and maintaining bat populations across restored landscapes.
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Bredenkamp, Brian Victor. "An analysis of correlated curve trend experiments in Eucalyptus grandis." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53915.
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Correlated curve trend (C.C.T.) experiments in Eucalyptus grandis on the Zululand coast of South Africa were analyzed. Growth parameters were described as functions of age using Schnute’s generalized growth function and parameter estimates were described as functions of stand density. Growth attributes were used as moments of a probability density function to describe a diameter distribution model for the species. Time trends in the relationships between growth parameters and stand density were scrutinized with multiple comparisons of paired means. It was shown that diameter growth in lower size classes ceases under conditions of extreme suppression while growth continues unabated in the larger size classes, resulting in greater dispersion in diameter. Competition mortality was to a large extent confined to the lower size classes and severe mortality results in an apparent increase in mean diameter which precludes use of growth functions which impose an asymptote. Allometric growth was investigated on two different sites and growth trends were shown to be anamorphic between sites. This permits a ratio approach to the estimation of growth and yield on one site based on experimental evidence from another. Thinning effects in terms of diameter and height changes were estimated from simulated thinnings using data from unthinned stands while the results of long-term thinning studies were compared in terms of cumulative volume yields. The age at which mean annual increment culminates was determined and a model for the estimation of m.a.i. as a function of age and stand density was constructed. A critical examination of spacing indices revealed that the slopes thereof were much steeper than those for many other species. The better-known indices of Reineke and Yoda were found to be dependent on age.Ph. D.
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Leitão-Lima, Patrícia da Silva [UNESP]. "Cornitermes cumulans Kollar, 1832 (Isoptera: termitidae ): preferência a diferentes substratos e avaliação de danos em plantas de Eucalipto." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/105393.
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A preferência de Cornitermes cumulans a diferentes substratos foi avaliada em condições de laboratório e em túnel plástico. No laboratório, foram preparados ninhos artificiais, com estrutura de plástico, contendo 300 operários, 50 ninfas e 50 soldados. Cada ninho foi colocado em uma arena, na qual foram oferecidos aleatoriamente os materiais testados, acondicionados em tubos de vidro. Os substratos foram oferecidos por período de 30 dias e, ao final, foi medido o volume carregado. Os tratamentos dos sete experimentos foram: 1 (bagaço de cana, serragem de Pinus, papelão ondulado, Multiplant, folhas secas de Brachiaria brizantha, feno de Cynodon sp. e vermiculita); 2 (esfagno, Plantmax estaca, Plantmax sementes, VCP 60%, Multiplant e vermiculita); 3 (esfagno, VCP 60%, VCP 20%, casca de arroz carbonizada e vermiculita); 4 (bagaço de cana, esfagno, VCP 60%, VCP 20%, Plantmax estaca, feno e vermiculita); 5 (esfagno, casca de arroz, vermiculita, VCP 60% e raízes do clone de eucalipto); 6 (Aracruz, Multiplant, Plantmax estaca, VCP 60%, VCP 20% e vermiculita). 7 (bagaço de cana, Cynodon, Plantmax estaca, esfagno, raízes de eucalipto, raízes de eucalipto + substrato VCP20% e vermiculita). Em túnel plástico, 10 colônias inteiras foram mantidas em vasos de 30 L, conectadas com as arenas com 20 mL de cada material. Os tratamentos foram os mesmos realizados no laboratório. O delineamento experimental, nas duas condições, foi o de blocos ao acaso com 10 repetições com 7 tratamentos nos experimentos 1, 4 e 7; 6 nos experimentos 2 e 6; 5 nos experimentos 3 e 5. A determinação dos danos de cupins, foi com a utilização de 10 colônias de cupins, cada colônia mantida em vasos de 30 L foi conectada a 4 mudas de eucalipto, outras 4 mudas não foram conectadas às colônias de cupins (testemunhas). As avaliações dos danos foram aos 15, 30, 60 e 90 dias após...
The preference of Cornitermes cumulans was evaluated in the laboratory and in a plastic tunnel in Botucatu, SP, Brazil. In laboratory, 300 workers, 50 nymphs, and 50 soldiers were maintained in arenas containing holes to fit glass vials filled with 7 mL of each treatment. The final volume was measured after 30 days. The treatments in the seven experiments consisted of: 1 (sugarcane bagasse, Pinus sawdust, corrugated cardboard, Multiplant, dry Brachiaria brizantha and Cynodon leaves, and vermiculite). 2 (sphagnum, Plantmax cuttings, Plantmax seeds, VCP 60%, Multiplant, and vermiculite). 3 (sphagnum, VCP 60%, VCP 20%, carbonized rice hulls, and vermiculite. 4 (sugarcane bagasse, sphagnum, VCP 60%, VCP 20%, Plantmax cutting, Cynodon, and vermiculite). 5 (sphagnum, rice hulls, vermiculite, VCP 60%, and roots of the VR 3748 clone). 6 (Aracruz, Multiplant, Plantmax cutting, VCP 60%, VCP 20%, and vermiculite. 7 (sugarcane bagasse, Cynodon, Plantmax cutting, sphagnum, eucalyptus roots, eucalyptus roots + VCP20% substrate, and vermiculite). In a plastic tunnel, 10 whole colonies were maintained in 30 L pots, connected with arenas containing 20 mL of each material. Treatments were the same as used in the laboratory. In both conditions, a random block experimental design was used, with 10 replicates, and 7 treatments in experiments 1, 4, and 7; 6 treatments in experiments 2 and 6; and 5 treatments in experiments 3 and 5. Termite damage was determined by using ten termite colonies; each colony, maintained in 30 L pots, was connected to four eucalyptus seedlings; another four seedlings were not connected to the termite colonies (control). Damage evaluations were done at 15, 30, 60, and 90 days after transplanting, with determinations for epigeal and root dry matter, height, leaf area, as well as eucalyptus root length, surface, volume, and diameter. The experimental...(Complete abstract click electronic access below)
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Leitão-Lima, Patrícia da Silva 1973. "Cornitermes cumulans Kollar, 1832 (Isoptera: termitidae ) : preferência a diferentes substratos e avaliação de danos em plantas de Eucalipto /." Botucatu : [s.n], 2005. http://hdl.handle.net/11449/105393.
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Orientador: Carlos Frederico WilckenBanca: Wilson Badiali Crocomo
Banca: Evoneo Berti Filho
Banca: Ronald Zanetthi Bonetti Filho
Banca: José Eduardo Marcondes Almeida
Resumo: A preferência de Cornitermes cumulans a diferentes substratos foi avaliada em condições de laboratório e em túnel plástico. No laboratório, foram preparados ninhos artificiais, com estrutura de plástico, contendo 300 operários, 50 ninfas e 50 soldados. Cada ninho foi colocado em uma arena, na qual foram oferecidos aleatoriamente os materiais testados, acondicionados em tubos de vidro. Os substratos foram oferecidos por período de 30 dias e, ao final, foi medido o volume carregado. Os tratamentos dos sete experimentos foram: 1 (bagaço de cana, serragem de Pinus, papelão ondulado, Multiplant, folhas secas de Brachiaria brizantha, feno de Cynodon sp. e vermiculita); 2 (esfagno, Plantmax estaca, Plantmax sementes, VCP 60%, Multiplant e vermiculita); 3 (esfagno, VCP 60%, VCP 20%, casca de arroz carbonizada e vermiculita); 4 (bagaço de cana, esfagno, VCP 60%, VCP 20%, Plantmax estaca, feno e vermiculita); 5 (esfagno, casca de arroz, vermiculita, VCP 60% e raízes do clone de eucalipto); 6 (Aracruz, Multiplant, Plantmax estaca, VCP 60%, VCP 20% e vermiculita). 7 (bagaço de cana, Cynodon, Plantmax estaca, esfagno, raízes de eucalipto, raízes de eucalipto + substrato VCP20% e vermiculita). Em túnel plástico, 10 colônias inteiras foram mantidas em vasos de 30 L, conectadas com as arenas com 20 mL de cada material. Os tratamentos foram os mesmos realizados no laboratório. O delineamento experimental, nas duas condições, foi o de blocos ao acaso com 10 repetições com 7 tratamentos nos experimentos 1, 4 e 7; 6 nos experimentos 2 e 6; 5 nos experimentos 3 e 5. A determinação dos danos de cupins, foi com a utilização de 10 colônias de cupins, cada colônia mantida em vasos de 30 L foi conectada a 4 mudas de eucalipto, outras 4 mudas não foram conectadas às colônias de cupins (testemunhas). As avaliações dos danos foram aos 15, 30, 60 e 90 dias após...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The preference of Cornitermes cumulans was evaluated in the laboratory and in a plastic tunnel in Botucatu, SP, Brazil. In laboratory, 300 workers, 50 nymphs, and 50 soldiers were maintained in arenas containing holes to fit glass vials filled with 7 mL of each treatment. The final volume was measured after 30 days. The treatments in the seven experiments consisted of: 1 (sugarcane bagasse, Pinus sawdust, corrugated cardboard, Multiplant, dry Brachiaria brizantha and Cynodon leaves, and vermiculite). 2 (sphagnum, Plantmax cuttings, Plantmax seeds, VCP 60%, Multiplant, and vermiculite). 3 (sphagnum, VCP 60%, VCP 20%, carbonized rice hulls, and vermiculite. 4 (sugarcane bagasse, sphagnum, VCP 60%, VCP 20%, Plantmax cutting, Cynodon, and vermiculite). 5 (sphagnum, rice hulls, vermiculite, VCP 60%, and roots of the VR 3748 clone). 6 (Aracruz, Multiplant, Plantmax cutting, VCP 60%, VCP 20%, and vermiculite. 7 (sugarcane bagasse, Cynodon, Plantmax cutting, sphagnum, eucalyptus roots, eucalyptus roots + VCP20% substrate, and vermiculite). In a plastic tunnel, 10 whole colonies were maintained in 30 L pots, connected with arenas containing 20 mL of each material. Treatments were the same as used in the laboratory. In both conditions, a random block experimental design was used, with 10 replicates, and 7 treatments in experiments 1, 4, and 7; 6 treatments in experiments 2 and 6; and 5 treatments in experiments 3 and 5. Termite damage was determined by using ten termite colonies; each colony, maintained in 30 L pots, was connected to four eucalyptus seedlings; another four seedlings were not connected to the termite colonies (control). Damage evaluations were done at 15, 30, 60, and 90 days after transplanting, with determinations for epigeal and root dry matter, height, leaf area, as well as eucalyptus root length, surface, volume, and diameter. The experimental...(Complete abstract click electronic access below)
Doutor
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Edwards, Todd A. "Environmental correlates and associations of tuart (Eucalyptus gomphocephala) decline." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2004. https://ro.ecu.edu.au/theses/800.
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Tuart (Eucalyptus gomphocephala DC.) is an ecologically and culturally important tree species that grows across a narrow 400 km long coastal belt, from the Sabrina River south of Perth, to Jurien Bay in the north. Unfortunately, Tuart is also a species under considerable threat due to clearing, lack of recruitment and canopy decline. Canopy decline is of particular concern, being increasingly reported throughout the Tuart distribution. Despite this, previous studies of Tuart have generally been limited to localised canopy decline events. This two-phased study firstly involved an assessment of Tuart canopy condition at 46 sites across the species distribution. At each study site the canopy condition of no Jess than 20 Tuart trees was assessed using estimations of canopy completeness, measures of canopy size reduction, and through the scoring of canopy condition indices. The second phase of the study involved collecting data on a wide selection of environmental factors considered to be important to canopy condition. These included factors of stand structure, understorey composition,landform (soil type, geology, topography, and geography), climate (gradients and change), hydrology (depth, depth change, and chemistry), fire regimes, pollution and anthropogenic disturbance (fragmentation and site disturbance). Assessment of canopy condition indicates that most the Tuart distribution has slight to moderate canopy decline, and is characterised by a mean canopy completeness of 70 percent. Most of this canopy decline is considered to be background (stand level) decline and likely to be a characteristic of the species. However, the lack of comparative studies using similar methodology makes the determination of the current state of Tuart canopy condition difficult. Long-term monitoring of Tuart canopy condition is therefore recommended to determine temporal trends in canopy condition. The main area of concern for Tuart conservation was found to be the Yalgorup region, where trees had typically less than 30 percent canopy completeness. Severe canopy decline in this region is similar to dieback reported in other eucalypt species from across Australia, that is, gradually receding canopy foliage leaving stag-headed trees and abundant epicormic foliage. Localised cases of canopy decline, similar in structure to that of the Yalgorup region, were found at Yellagonga, Neerabup and Ludlow National Park. Investigations into environmental factors found severe canopy decline in the Yalgorup region is associated with higher rainfall, finer and shallower soil, higher groundwater alkalinity and salinity, and greater rates of groundwater salinity increase. Elsewhere Tuart canopy decline was found to be associated with nutrient enrichment (high topsoil ammonium nitrogen) and high levels of fragmentation. Environmental factors other than those mentioned do not appear to be causing Tuart canopy decline across the distribution, for example understorey competition, altered fire regimes and climate change. Future management of Tuart canopy decline needs to focus on the severe canopy decline in the Yalgorup region, and build upon the hypotheses proposed in this study to explain canopy decline. Low recruitment should also not be forgotten as a major cause of the species decline.
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Tng, DYP. "Are giant eucalypt forests rain forest?" Thesis, 2014. https://eprints.utas.edu.au/22738/1/Tng_whole_thesis_ex_pub_mat.pdf.
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Forests dominated by giant eucalypts ( eucalypt species with the potential to attain heights exceeding 70m) occur along the Australian east coast in association with rain forest. These forests contribute significantly to the global carbon budget but their ecological classification suffers from ambiguities around the definition of rain forest. The belief that eucalypts are 'sclerophyllous' and therefore not rain forest is a subjective view that has led to problems with conservation policies and management strategies of giant eucalypt forests. Understanding these forests from a global and functional viewpoint is paramount for their effective management. Eucalyptus grandis-dominated giant eucalypt forests in the Wet Tropics of Australia serve as a case study. Observing that rain forest species continuously regenerate in the understories of these eucalypt forests and believing that rain forest incursion will lead to the local elimination of the giant eucalypts, land managers prescribe frequent, low intensity fires. This management strategy is contentious and not underpinned by robust ecological understanding. To resolve these classificatory problems around eucalypts occurring in rain forest, I take a multidisciplinary approach to address the specific question: Are giant eucalypt forests rain forests?
To obtain an in depth understanding of the ecology of giant eucalypts and the forests they dominate, and to provide a global context for these systems, I synthesise over a century's worth of literature on these systems (Chapter 2). Based on these data I propose that giant eucalypts are ecologically akin to rain forest emergent pioneers with a unique dependence on fire for regeneration, and that their habitat should be considered a type of secondary rain forest.
Using a GIS-based approach I investigate the landscape scale vegetation dynamics of rain forest and E. grandis forest in the Wet Tropics, where E. grandis forests are considered to be threatened (Chapter 3). Using a environmentally stratified sample of sites, I show that rain forest has expanded over the past 50 years, and that this expansion is most likely a response to a global driver such as increased atmospheric CO2 rather than with local environmental factors. Projective modelling of this rain forest expansion predicts that, even at the fastest estimated rate known for the region, it will be more than 2000 years before rain forest fully engulfs giant eucalypt forests.
In Chapter 4, I present a seedling growth experiment to examine if the regeneration niche of E. grandis exhibits ecological convergence with that of well-studied temperate giant eucalypts. I show that E. grandis seedlings grow poorly in unburnt rain forest soils because of the unavailability of phosphorus. The addition of phosphorus lifts phosphorus-deficiency symptoms in seedlings in rain forest soils, and accords well with the idea of E. grandis being a rain forest pioneer with the unique requirement of fire as a disturbance mechanism to create suitable open habitats for regeneration.
To contextualize the rain forest- giant eucalypt forest - savanna transitions in Australia from a functional and macroecological perspective, I present a plant functional trait analysis of representative plants across these vegetation transitions in both tropical and temperate Australia (Chapter 5). I show that both tropical and temperate giant eucalypt forest are functionally convergent with rain forest and not with savanna. These results suggest that a classification of giant eucalypt forest based on functional attributes of the whole forest will be more useful for management policy than the established classification based on canopy dominants.
In conclusion (Chapter 6), the synthesis ofmy landscape ecology and functional biology data supports my overarching hypothesis that giant eucalypt forests are functionally and ecologically rain forests and should be managed as such. I discuss the implications of my research for the management of Wet Tropics giant eucalypt forest and recommend that E. grandis forest should be managed under a regime of total fire suppression. Given that rare natural fires can be expected to occur under this management, the resulting regime will mimic the inherently long fire return times of these systems.