To see the other types of publications on this topic, follow the link: Forest management of tropical rain forests.
Dissertations / Theses on the topic 'Forest management of tropical rain forests'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Forest management of tropical rain forests.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Ramdass, Indarjit. "Modelling forest dynamics and management of natural tropical rain forests." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/11890.
Full text
2
Silva, J. N. M. "The behaviour of the tropical rain forest of the Brazilian Amazon after logging." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276556.
Full text
3
Richards, Michael. "Economic incentives for the sustainable management and conservation of tropical forests." Thesis, University of South Wales, 2007. https://pure.southwales.ac.uk/en/studentthesis/economic-incentives-for-the-sustainable-management-and-conservation-of-tropical-forests(eb11e629-42d7-4fbf-924c-769ac6a42471).html.
Full textAbstract:
This PhD by Publication traces through 13 of my publications on economic incentives for forest management and conservation in tropical countries (with a regional bias towards Latin America), including several papers focused on participatory forest management or community-based conservation. The papers show how my thinking has evolved from a focus on market and nonmarket incentives, to an increasing emphasis on governance and regulatory incentives in explaining stakeholder behaviour to the forest resource, as well as the equity impacts. They reveal that positive incentives and win-win (environmental and poverty reduction) outcomes will only emerge when the underlying market, policy and institutional failures are tackled. Because of their public good values, the survival of tropical forests is contingent on the actions of the international community and governments. Sustainable forestry, therefore, depends on a combination of domestic governance progress to control illegal logging and the rent-seeking powers of vested interest groups, global governance regulations which create markets for environmental services, secure property rights for resident stakeholders and extra-sectoral policies that moderate land use opportunity costs. The current main hope for tropical forests is 'avoided deforestation' since this will need to tackle the forest governance problems and underlying multi-sectoral drivers of deforestation if it is to be successful. It represents a balanced market (payments for ecosystem services) and supply-side (improved governance) response to what is essentially a 'public goods' management problem, but will need to overcome some major political economy challenges.
4
Fah, Lee Ying. "Genetic and ecological studies relevant to the conservation and management of some Bornean Calamus species." Thesis, University of Aberdeen, 1995. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU603181.
Full textAbstract:
Genetic variation in Calamus subinermis was investigated in a provenance cum progeny trial and a study on some quantitative morphological traits. These studies show that variation occurs within and among populations of the species. Genetic gain was estimated for provenance and family selection at a range of selection intensity based on some economic traits. A karyomorphological study on C. subinermis and C. caesius reveals little variation in the chromosome morphology between and within species. The flowering and fruiting phenology of C. subinermis, C. caesius, C. manan and C. trachycoleus was elucidated. Except for the relatively opportunistic C. subinermis, in which floral initiation occurred at about four-month intervals, flowering and fruiting of the Calamus species investigated exhibited a regular annual pattern. Unravelling of the pollination mechanism and floral biology of C. subinermis and C. caesius in this project enables understanding of the breeding system and is important in breeding programmes. Pollination mainly by small noctuid and pyralid moths, which have small foraging ranges, partly accounts for the observed divergence among geographically isolated populations of C. subinermis. The discovery of andromonoecy in C. subinermis, together with the potential bisexuality in the other generally dioecious calamoid genera, calls for modification in the present system of classification for the tribe Calameae, and has implications for natural and artificial pollination. Several rattan mensuration techniques were developed. Growth and yield models based on the Richards function were constructed for C. caesius. These techniques and models will contribute to the conservation with wise use of rattan resources. Recommendations for further research are given for attaining the goal of the project.
5
Mayhew, Rebekah Jane Watts. "The species and functional composition of bird communities in regenerating tropical forests." Thesis, University of Stirling, 2017. http://hdl.handle.net/1893/27894.
Full textAbstract:
The widespread threat of species extinctions caused by the destruction and degradation of tropical primary forest (PF) could potentially be mitigated by the expansion of regenerating secondary forest (SF). However, the conservation value of SF remains controversial, and is dependent on many site- and landscape-scale factors, such as habitat age and isolation. The aim of this thesis was to assess the role that SF can play in conserving forest bird communities in central Panama. We study a chronosequence of SF aged 20 – 120-years-old, with sites either isolated from or connected to extensive PF. Our results suggest that SF supports high levels of avian species diversity, and similar community composition to PF. Whilst forest age plays a small role in determining compositional similarity to PF, connectivity to extensive PF was the main determinant of community composition. However, despite high species richness and complex community composition, some specialist PF bird species were consistently absent from SF, and isolated PF. The functional diversity of bird communities did not vary substantially across the forest age and isolation gradient, although we did find some inter-guild differences; with distinct responses in communities of avian insectivores and frugivores. Isolation caused shifts in the trophic traits of insectivores, but resulted in alterations in the dispersal traits of frugivores. The response of bird and tree community composition to forest age and isolation was similar, although isolation had a stronger impact on bird communities. Bird diversity and composition tracked changes in forest structure over succession. When examining the role of birds in seed-dispersal networks, we found bird gape width was the key predictor of seed size consumed. Large-gaped birds consume a wider variety of seed-sizes than small-gaped birds, and small-seeded trees attract a greater number of bird species than large-seeded trees. These results imply high levels of redundancy among small-gaped avian frugivores and small-seeded plant species, but low levels of redundancy among large-seeded plant species and their avian dispersers. This suggests that large-seeded plants may be most at risk of dispersal failure following any change in avian frugivore assemblages. Together, these results suggest that SF can play a key role in sustaining most tropical biodiversity, and in maintaining ecosystem services. Our findings emphasise the importance of integrating SF into conservation strategies to support and buffer tropical PF habitats.
6
Li, Fui Yee. "Factors affecting tree seedling establishment following rehabilitation management in logged-over tropical rain forest in Sabah, Malaysia." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429982.
Full text
7
Abe, Hitofumi. "Forest management impacts on growth, diversity and nutrient cycling of lowland tropical rainforest and plantations, Papua New Guinea." University of Western Australia. School of Plant Biology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0098.
Full textAbstract:
[Truncated abstract] Globally, tropical rainforests are noted for their high biodiversity and key roles in carbon storage and influence on climate. Nevertheless, tropical deforestation in many parts of the world continues at an alarming rate. In Papua New Guinea (PNG), tropical rainforest is relatively well maintained, with about 70 % of the land area still covered by primary forest. However, PNG's native forests are coming under increasing pressure, particularly from selective logging for high quality timber. While the forests of PNG, and more broadly the entire New Guinea Island, are recognised as of high conservation and ecological significance, they remain grossly understudied with little knowledge of key ecosystem processes within lowland forests in particular. Such knowledge is urgently required if the impacts of logging and other land-use change are to be assessed and in order to develop sustainable management systems. This thesis investigated the impacts of logging on diversity and nutrient cycling in a lowland tropical rainforest growing on limestone soils in the area of the Mongi-Busiga Forest Management Agreement (FMA, which is a logging concession area), in northeastern PNG. These forests are on relatively young soils and provide a useful contrast to the majority of tropical forests. The research includes a four-year study of the recovery of diversity and structure after logging, and quantified forest structure, tree species diversity, forest biomass and productivity, and nutrient distribution and cycling. This thesis also examines the ecological sustainability of Eucalyptus deglupta plantations in Wasab, PNG as an alternative resource for timber and biomass energy. The thesis concludes with a discussion of long-term forest recovery and sustainable forest management in north-eastern PNG. Two adjacent one-hectare plots were established in lowland tropical rainforest at Mongi-Busiga FMA. One of these plots was subsequently selectively logged, one year after establishment. Before logging, the two one-hectare plots contained a total of 37 families, 70 genera and 110 tree species that were >5 cm in diameter at breast height. Mean basal area was 42.4 m2 ha-1. Two tree species, Madhuca leucodermis (Sapotaceae) and Pometia pinnata (Sapindaceae) accounted for ~60% of the total basal area. Gymnacranthera paniculata (Myristicaceae) was the most common species and accounted for 13% of individuals. ... This study concludes that the Mongi-Busiga forest has many unusual characteristics for a tropical forest, including relatively low diversity of tree species, high accumulation of P in the biomass, and N limitations, compared to other tropical rainforests. However, those extraordinary characteristics may be explained well by the underlying geology of young, marine-derived limestone. Sustainable management of the lowland tropical forests of PNG should consider the consequences of logging on nutrient cycling processes, with the possible significant removal of P from site with repeated logging, as well as the interactions between N and P in these systems. Establishment of Eucalyptus plantations on previously cleared land also has the potential to meet some of the timber and biomass energy requirements of northern PNG in ecologically sustainable manner.
8
Kefa, Christopher Amutabi. "Assessing the Impacts of Bioenergy Extraction and Human Land Use of the Biodiversity of Kakamega Tropical Rainforest, Kenya." Bowling Green State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1465254368.
Full text
9
Lu, Yuanchang. "Development of models for sustainable management of the mixed tropical rain forests in Xishuangbanna, Yunnan Province, PR of China /." Göttingen : E. Goltze, 1999. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009061492&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
Full text
10
Condé, Tiago Monteiro. "Avaliação dos impactos na vegetação após a exploração madeireira em floresta ombrófila densa de terra firme no Município de Caracaraí - RR." Universidade Federal de Roraima, 2011. http://www.bdtd.ufrr.br/tde_busca/arquivo.php?codArquivo=98.
Full textAbstract:
Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorForam avaliadas as alterações na composição florística, fitossociologia e danos em floresta submetida à exploração madeireira de impacto reduzido (EIR) no município de Caracaraí, no estado de Roraima. O experimento consistiu na instalação de nove parcelas permanentes (1 hectare cada), sob o elineamento inteiramente casualizado, com três repetições e três tratamentos (T1 = floresta natural; T2 = floresta submetida a exploração de impacto reduzido + corte de cipós; T3 = floresta submetida a exploração de impacto reduzido + corte de cipós + desbaste por anelagem). Antes da exploração madeireira, foram encontrados 4.724 indíviduos, distribuídos em 42 famílias botânicas, 111 gêneros e 165 espécies, sendo que as famílias botânicas que apresentaram maior número de indivíduos foram: Fabaceae (1.883), Lecythidaceae (609), Sapotaceae (434) e Arecaceae (254). As três espécies com os maiores valores de índice de importância (IVI), em ordem decrescente, foram: Pentaclethra macroloba (52,06%), Eschweilera bracteosa (23,72%) e Pouteria caimito (8,10%). Após a exploração madeireira de impacto reduzido realizada na intensidade média de 3 árvores extraídas por hectare (DAP > 50 cm), correspondente a 18,66 m3/ha e aplicação dos tratamentos silviculturais, não foram encontradas alterações significativas na composição florística, fitossociologia e nas freqüências diamétricas da floresta. A diversidade e equabilidade da floresta também não sofreram alterações significativas (Antes: Shannon = 3,27 e Pielou = 0,64; Após: Shannon = 3,26 e Pielou = 0,64). A exploração madeireira gerou uma média de 41 árvores danificadas/ha e 32 árvores mortas/ha, que correspondem a 15 árvores danificadas por árvore colhida por ha e 12 árvores mortas por árvore colhida por ha. A maior parte dos danos causados à vegetação remanescente resultou da formação de clareiras devido à extração de árvores comerciais da floresta, sendo superior ao impacto causado pela construção de trilhas de arraste. Foram observadas reduções de 5,96% e 18,90% no volume cormecial (DAP > 10 cm) em T2 e T3, respectivamente.
Changes on floristic composition and phytosociological and damage we evaluated in forest subjected to reduced-impact logging (RIL) in the municipality of Caracaraí in the state of Roraima. The experiment consisted in the installation of nine permanent plots (1 ha each), under the completely randomized design with three replications and three treatments (T1 = natural forest; T2 = forest subjected to reduced-impact logging + vine cutting; T3 = forest subjected to reduced-impact logging + cutting vines + girling). Before logging, 4.724 individuals were found, distributed in 42 botanical families, 111 genera and 165 species, and the plant families with the highest number of individuals were Fabaceae (1883), Lecythidaceae (609), Sapotaceae (434) and Arecaceae (254). The three species with the highest values of IVI, in descending order, were: Pentaclethra macroloba (52,06%), Eschweilera bracteosa (23,72%) and Pouteria caimito (8,10%). After the reduced-impact logging (RIL) with 3 trees extracted per hectare (DBH > 50 cm), corresponding to 18,66 m3/ha and application silvicultural treatments, we found no significant changes in floristic composition and phytosociological and diametric frequencies in the forest. The forest diversity and equability did not change significantly (before: Shannon = 3,27 and Pielou = 0,64; After: Shannon = 3,26 and Pielou = 0,64). Logging generated an average of 41 damaged trees / ha and 32 dead trees / ha, equivalent to 15 damaged trees per harvested tree per ha and 12 dead trees per harvested tree per ha. Most damage to remaining vegetation resulted in the formation of gaps due to the commercial extraction of forest trees, higher than the impact caused by construction of skid trails. Reductions of 5.96% and 18.90% in volume cormecial (DBH > 10 cm) in T2 and T3, respectively.
11
Manokaran, N. "Population dynamics of tropical forest trees." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 1988. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=59678.
Full text
12
Zakaria, Maziah. "Colletotrichum diseases of forest tree nurseries in Malaysia." Thesis, University of Bristol, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295495.
Full text
13
Wilebore, Rebecca. "Valuing forests in tropical landscapes in the context of REDD+." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709048.
Full text
14
Baker, Timothy Russell. "Spatial and temporal patterns of growth in Ghanaian tropical rain forest." Thesis, University of Aberdeen, 2000. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU603191.
Full textAbstract:
This thesis tests the hypothesis that variation in water supply, nutrient availability and irradiance determined variation in tree growth along local and regional gradients of resource availability, and over time, in Ghanaian forests. Regional variation in soil water availability determined seasonal patterns of diameter change of Celtis mildbraedii and Strombosia glaucescens in semi-deciduous and evergreen forest, over two years. However, in a semi-deciduous forest, annualized diameter increment of Celtis mildbraedii was higher in summit and slope, compared to valley, positions after two years, even though trees in valley positions experienced a shorter effective dry season. Growth was also greater in the semi-deciduous than the evergreen forest in the second year of the study. These patterns suggest that concentrations of N in soil over topographic gradients, and concentrations of available P and the base cations over regional scales, may be important determinants of growth. Dry season stem shrinkage in semi-deciduous forest can comprise up to 0.5% of tree diameter, and varies between years. Re-enumeration of forest plots in seasonal climates should be carried out over whole year intervals, during the wet season, to minimise bias derived from variation in tree water status. In a semi-deciduous forest, no relationship was found between topography and six year growth rates of two common species or of six functional types defined on the basis of regeneration strategy and regional distribution pattern. However, within this forest, and in a comparison within five different forests across the regional gradient of rainfall and soil fertility, pioneer species with distributions biased towards drier forests had significantly higher growth rates than pioneer species associated with wetter forests. Variation in growth of dry forest pioneer species explained more than half the total variation in stand-level growth rates, demonstrating that it is the presence of abundant, potentially large, fast growing pioneer species in more seasonal forest types that generate regional scale variation in forest growth. These results indicate that the environmental variables found to determine growth are dependent on the scale of the study and the magnitude of the gradient in resources being compared. Variation in soil fertility over regional rainfall gradients in tropical forests has a significant impact on variation in tree growth, within and between species, and at the stand-level.
15
Mitchell, Thomas Carly. "The ecology of Macaranga (Euphorbiaceae) trees in primary lowland mixed Dipterocarp forest, Brunei." Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/251702.
Full text
16
Orlando, Heloisa Helena R. V. "The fragmented forest : environmental conservation and legal protection in reserve areas in the Brazilian Amazon rain forest." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284285.
Full text
17
Coomes, David Anthony. "The effects of root competition on saplings and seedlings in Amazonian caatinga forest in southern Venezuela." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361641.
Full text
18
Ilstedt, Ulrik. "Soil degradation and rehabilitation in humid tropical forests (Sabah, Malaysia) /." Umeå : Swedish University of Agricultural Sciences, 2002. http://diss-epsilon.slu.se/archive/00000233/.
Full textAbstract:
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002.Abstract inserted. Appendix reprints four papers and manuscripts co-authored with others. Includes bibliographical references. Also partially issued electronically via World Wide Web in PDF format; online version lacks appendix.
19
Grainger, A. "The future role of the tropical rain forests in the world forest economy." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377888.
Full text
20
Ellis, Alexander 1972. "Global change and tropical forests : functional groups and responses of tropical trees to elevated CO." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27312.
Full textAbstract:
The paradox of tropical forests is that they are simultaneously the most diverse, the least understood, and the most imperiled terrestrial ecosystem in the world. Dramatic increases in the atmospheric carbon dioxide (CO$ sb2$) concentration threaten to adversely affect fundamental climatic and ecosystem processes, gradually changing many things which we do not yet understand. Although the impacts of this rise have been studied in temperate areas, little research has investigated tree responses in the tropics, especially under natural frost conditions. This thesis examines three central issues in tropical ecophysiology and global change. First, it investigates the feasibility of in-situ measurements of several physiological traits under heterogeneous environmental conditions in a Panamanian rainforest. Second, it studies whether physiological traits differ among species and which traits are most consistent with ecological niche. Finally, it explores how variable species are in response to elevated CO$ sb2$. If ecologically-defined functional groups were to remain physiologically similar under increased CO$ sb2$, they could be used in accurately representing the variation at the species level in a global change model of system-level responses. (Abstract shortened by UMI.)
21
Morris, Michael William. "Amazopoly a game of survival in a tropical rain forest." CSUSB ScholarWorks, 1996. https://scholarworks.lib.csusb.edu/etd-project/34.
Full text
22
Still, Margaret Jean. "Population dynamics and spatial patterns of Dipterocarp seedlings in a tropical rain forest." Thesis, University of Stirling, 1993. http://hdl.handle.net/1893/26682.
Full textAbstract:
Population dynamics and spatial pattern of dipterocarp seedlings were investigated in lowland dipterocarp forest in Danum Valley Conservation Area, Sabah, East Malaysia. Seedlings (< 10 cm gbh) were enumerated in two areas (2.0 and 0.48 ha) within the tree enumeration plots established by the University of Stirling project, and surveyed over 22 months. Seedlings of the major canopy and emergent dipterocarps in the area were common: Shorea johorensis (Red Meranti); S. argentifolia, S. leprosula, S. parvifolia (Light Red Merantis, LRM) and Parashorea maleanonan, all light demanding species; S. fallax,S. pauciflora (Dark Red Meranti, DRM), more shade tolerant emergent species; and Hopea nervosa, Vatica dulitensis and V. sarawakensis, shade tolerant canopy species. Total seedling densities were 2000-2500 ha-1. Mortality rates varied from 0 to 16% yr-1 in different species, and were highest in the LRMs and lowest in the canopy species. Temporal and spatial variation in mortality rates was greatest in the LRMs. In both plots, seedling mortality rates were significantly positively correlated with basal area of conspecific trees ≥10cm gbh. Net growth rates were very variable, even within size classes in the same species. Median growth rates were highest in the LRMs and lowest in canopy species. Frequency distributions of growth rates were strongly leptokurtic in slow-growing species, with most seedlings having growth rates around zero, although individual seedlings could produce large increments. In fast-growing species, more seedlings achieved high growth rates. A significant proportion of seedlings suffered height loss due to falling debris, and almost half the seedlings showed evidence of previous stem damage. Large growth increments were recorded in most species in response to canopy openings, usually very small gaps caused by branch falls. Individual increments exceeded 1 m yr-1 in seven species. Growth and mortality rates were significantly positively correlated across species in Plot 1, but not in Plot 2. Seedling spatial patterns were examined in eleven species in Plot 1, and covered a wide range of degrees of aggregation. Seedlings of the light-demanding emergent species were we1l-distributed throughout the study area, though some showed aggregation at a small scale. DRM seedlings were strongly clumped around adult trees. Seedlings of two of the canopy species were very strongly aggregated around adult trees, while the third species, V. sarawakensis, had randomly distributed seedlings.
23
Kaye, Maria Ellen. "The role of functional traits and phylogeny in assembly of tropical forest communities in Danum Valley, Sabah." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231264.
Full textAbstract:
Tropical forests have been studied by community ecologists since the earliest days of the field because of their diversity and complexity and much of the theory behind community assembly has been developed in the tropics. However, the processes that act to assemble species in tropical forest across a very fine scale are still poorly understood. This study investigates community structure in 20ha area of hyper diverse tropical rainforest in Sabah, Malaysia. In order to examine community phylogenetic structure, I reconstructed a molecular phylogeny for all species in the study site using DNA barcoding loci. From this, I calculated phylogenetic diversity metrics for each community and then used a null model to compare observed phylogenetic diversity with that which would be expected if communities were randomly assembled with respect to phylogeny. The analyses showed that communities are more closely related than predicted by the null model. I also collected species functional trait data and showed that species assemblages and community weighted mean trait values correlate with environmental gradients on the plot. I also compared functional diversity to data simulated from null models. This showed that communities are on average more functionally similar than predicted at random. Finally, I performed a multivariate analysis with environmental, spatial, phylogenetic and trait data from communities across the plot. The analyses recovered an elevational and soil gradient that correlated strongly with community composition. Species occupying different ranges along this gradient had differing trait values and were phylogenetically distinct. These analyses demonstrate that even fine scale environmental variation is influential in assembling communities over a small area of forest. A soil nutrient gradient is consistently recovered that correlates with topography, suggesting that soil nutrient distribution is mediated by the downslope movement of water leaching soils on ridge tops and leading to accumulation of nutrients in valleys. This gradient is associated with species compositional variation and also with community weighted mean functional traits, indicating that the environment is influencing species distributions even over very small areas. Communities were both functionally and phylogenetically clustered, adding further support to this conclusion.
24
Latifah, Sitti. "Inventory and quality assessment of tropical rainforests in the Lore Lindu National Park (Sulawesi, Indonesia) /." Göttingen : Cuvillier, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=013215823&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
Full text
25
Morokawa, Tokitika. "Modelagem da din?mica de crescimento de uma Floresta Ombr?fila aerta do estado de Rond?nia." Universidade Federal Rural do Rio de Janeiro, 2009. https://tede.ufrrj.br/jspui/handle/tede/490.
Full textAbstract:
Made available in DSpace on 2016-04-28T14:56:37Z (GMT). No. of bitstreams: 1
2009 - Tokitika Morokawa.pdf: 5650089 bytes, checksum: a8d1865101e3a9effdd865554b069415 (MD5)
Previous issue date: 2009-02-05A model of the growth dynamics of forests was developed applying Bertalanffy growth model (BGM) y=a[(1 e bt)c] for individual trees. Based on linearized relationship with diameter and height equation LnH=b0+LnD and volume equation V=b0Db1Hb2 mutually compatible equations for diameter, basal area, height and volume were generated, adjusting parameters a and c of BGM. Additionally, it was developed a methodology based on DBH measurements in two occasions and the estimate value of parameter a to get the values of parameter c and b of BGM. The data of the inventory of 1,061 trees over 40cm DBH of 67.5 hectares of tropical rain forest of Aquariquara Extractive Reserve, located in State of Rondonia, Brazil, were used to test the developed model. These data were grouped in nine maximum diameter (Dmax) classes. The tree survival was estimated based on the frequency of trees by relative age class. The input and output of each tree was adjusted considering a closed and stable population with replacement of a dead tree by the ingrowth of the same specie of tree with 40cm DBH. Applying the model to such data and simulating the growth dynamics of the forest in a time frame of 1500 years (T1 → 1,500), the difference of simulated annual average, in relation to the observed values in the year T0 of the forest inventory was -2.09% in age, -0.33% in height, -0.96% in diameter, -3.41% in basal area, -3.81% in volume and +1.81% in merchantable trees value. The average values of T1→500, T501→1000 and T1001→1500 periods were equal for all variables by Kruskal-Wallis test (p=0.05). The simulation showed that one hectare of this forest maintains a total stock composed of 15.72 120-year-old trees, accumulated 4.35m2 of basal area and 37.98m3 wood volumes on average. The annual input flow of the system was 0.3457 88-year-old trees which accumulated 0.0441m2 of basal area and volume of 0.3265m3. The output of the system consists of 0.3459 132-year-old trees totaling 0,1127m2 of basal area and 0.9911m3 in volume. The annual input and output rates were, respectively, 2.20 and 2.20% in number of trees, 1.01 and 2.59% in basal area and 0.86 and 2.61% in volume. In addition, the simulation indicated that it is possible to sustain an average annual production of 0.5528m3 of merchantable timber generating R$5.50 (about US$1.49) annual income per hectare of forest. The simulation showed that the model developed describes growth dynamics of tropical forest. However, it needs to be properly adjusted based on real growth of each individual tree and flows of input and output of trees in the system.
Nesta tese foi desenvolvida a modelagem da din?mica de crescimento de uma floresta, aplicando-se o modelo de crescimento de Bertalanffy (MCB) y=a[(1 e bt)c] para ?rvores individuais. Baseando-se nas rela??es linearizadas entre o di?metro e altura da equa??o LnH=b0+LnD e do di?metro com volume V=b0Db1Hb2 foram geradas equa??es de crescimento reciprocamente compat?veis entre di?metro, ?rea basal, altura e volume, ajustando-se os valores dos coeficientes a e c do MCB. Adicionalmente, foi desenvolvida metodologia, baseando-se em medi??es de DAP de cada ?rvore em duas ocasi?es e com a estimativa do coeficiente a, para obter os valores dos coeficientes c e b do MCB. Para testar o modelo desenvolvido foram utilizados numa simula??o os dados de invent?rio de 1.061 ?rvores, com DAP≥40cm, de uma ?rea de 67,5ha de Floresta Omb?fila Aberta da Reserva Extrativista Aquariquara, localizada no munic?pio de Machadinho D?Oeste, estado de Rond?nia. Estes dados foram agrupados em nove classes de di?metro m?ximo (Dmax) compreendidas entre 50 e 240cm, mantendo-se uma amplitude entre elas de 10cm. A taxa de sobreviv?ncia da ?rvore foi estimada baseando-se na freq??ncia de ?rvores por classe de idade relativa. O sistema de entrada (input) e sa?da (output) de cada ?rvore foi ajustado considerando uma popula??o fechada e est?vel com substitui??o de uma ?rvore morta pela entrada de ?rvore da mesma esp?cie com DAP≥40cm. Em rela??o aos valores observados no ano T0 do invent?rio florestal, as m?dias anuais dos valores simulados da din?mica de crescimento dessa floresta num horizonte temporal de 1.500 anos (T1→1.500), apresentaram diferen?as m?dias de -2,09% em idade, -0,33% em altura, -0,96% em di?metro, -3,41% em ?rea basal, -3,81% em volume e +1,81% em valor da ?rvore em p?. As m?dias anuais dos valores simulados dos per?odos T1→500, T501→1.000 e T1.001→1.500 foram iguais para todas as vari?veis pelo teste de repetibilidade de Kruskal-Wallis (p=0,05), mostrando que o modelo ? est?vel no tempo. A simula??o mostrou que esta floresta mantem em m?dia um estoque total de massa em crescimento composta de 15,72 ?rvores.ha-1 com 120 anos de idade acumulando um total de 4,35m2.ha-1 de ?rea basal e 37,98m3.ha-1 de volume de madeira. O fluxo anual de ingresso no sistema foi de 0,3457 ?rvores com 88 anos de idade que somaram 0,0441m2 de ?rea basal e 0,3265m3 de volume, e de sa?da do sistema composto de 0,3459 ?rvores com 132 anos de idade que somaram 0,1127m2 de ?rea basal e 0,9911m3 de volume por hectare, resultando em taxas de ingressos e sa?das anuais, respectivamente, de 2,20 e 2,20% em n?mero de ?rvores, 1,01 e 2,59% em ?rea basal e 0,86 e 2,61% em volume. Al?m disso, a simula??o indicou que ? poss?vel sustentar uma produ??o m?dia anual de 0,5528m3 de madeira de valor comercial gerando renda anual de R$5,50 por hectare (a pre?o corrente de outubro de 2002) de floresta. A simula??o mostrou que o modelo desenvolvido descreve a din?mica de crescimento de floresta tropical, por?m ele necessita ser devidamente calibrado tomando os dados de crescimento real de cada ?rvore individual e dos fluxos de ingressos e sa?das de ?rvores do sistema.
26
Mustafa, Bakray Nur Aqilah Binti. "Structure of root associated and soil fungal and bacterial communities in Southeast Asia tropical forest." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=239153.
Full textAbstract:
The tropical rainforest has interested ecologists for hundreds of years because of its vast species diversity. The distribution and establishment of trees is related to soil properties and rootassociated microorganisms. The coexistence of hyper-diverse plant communities in tropical rainforests has resulted in associations being formed with belowground communities, mycorrhizas (particularly arbuscular mycorrhizal (AM), ectomycorrhizas (ECM)) and root associated bacterial communities. The rapid deforestation in Southeast Asia is causing the loss of the dominant and important tree species belonging to the family Dipterocarpaceae. It is important to understand whether different host species in the same environment maintain mycorrhizal and bacterial diversity, especially mycorrhizas with a restricted host range. In this study, I examine the ecology of mycorrhizas and bacteria associated with Dipterocarpaceae and also the plant community as a whole. The aim of this project is to understand the effect of host properties (e.g. species, size), soil factors (e.g. nutrient concentrations) and spatial factors on mycorrhizal fungi and bacterial diversity and community structure. The research took place in two Centre for Tropical Forest Science (CTFS) plots in Malaysia: Pasoh Forest Reserve (in Negeri Sembilan) and Danum Valley Conservation Area (in Sabah). Molecular protocols and a modern technique, Next Generation Sequencing (NGS), were adopted to quantify mycorrhizal and bacterial loads in tropical plants. ITS1 and ITS2 regions were used for ECM, 18S rRNA were used for AM, and 16S rRNA were used for bacteria. Mycorrhizas and bacteria present in the roots of Dipterocarpaceae from 60 individual plants belonged to 25 species within 6 genera were traced and sampled in 2015. To my knowledge, this study is the first attempt to study root-associated bacteria across multiple species within a single family, Dipterocarpaceae. Dipterocarpaceae's species was found to significantly influence root bacteria. Analyses showed that mycorrhizal communities are similar on the host, unlike the null model. Dipterocarpaceae was previously believed to solely host ECM, but this study disproves this. This study shows that Dipterocarpaceae can have dual colonization, as it iv can also associate with AM fungi. One soil core of 10 cm × 10 cm × 7.5 cm were collect randomly in three subplot and further divided at 2.5 cm each slice into 75 individual 'microcubes' of 2 cm × 2 cm × 2.5 cm depths enumerates a total of 192 fine root samples. Multivariate analysis revealed that AM fungi tend to associate with non-dipterocarp (as well as unidentified families) while ECM fungi tend to associate with dipterocarps. Data was also collected on host attributes, plant size, and root density. Dipterocarpaceae size does not influence the distribution of mycorrhizal or bacterial communities. The root density reduces as depth increases. Therefore, root density does have a significant influence on mycorrhizal community structure. The diversity of ECM and AM fungal communities within cubes decreased significantly with depth (p < 0.001), whereas the mycorrhizal communities did not change across horizontal distances within cubes. To investigate whether there is a relationship between belowground communities and soil properties, soil macro and micro nutrients were examined and a multivariate analysis was performed. The results showed that communities of belowground (mycorrhizal and bacterial) species correlate with soil parameters. Spatial scale also had an effect on community assembly, independent of environmental variation. These results demonstrate that mycorrhizal fungal communities can vary substantially over very fine spatial scales, and that the distribution of roots from different species do not reflect their proximity aboveground. This study clearly demonstrates the widespread presence of mycorrhizal fungi and root associated bacteria in tropical rainforest plants.
27
Perera, G. A. Dhammika. "Regeneration and succession following shifting cultivation and dry tropical deciduous forests of Sri Lanka." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242827.
Full text
28
Cunningham, Shaun Cameron 1971. "Comparative ecophysiology of temperate and tropical rainforest canopy trees of Australia in relation to climate variables." Monash University, Dept. of Biological Sciences, 2001. http://arrow.monash.edu.au/hdl/1959.1/9040.
Full text
29
Luizao, Regina C. C. "Soil biological studies in contrasting types of vegetation in central Amazonian rain forests." Thesis, University of Stirling, 1994. http://hdl.handle.net/1893/2274.
Full textAbstract:
Studies were carried out in a lowland evergreen rain forest (LERF), on an ultisol, in the 'Reserva da Campina', 45 km north of Manaus, and in two facies of the highly distinct formation called heath forest, on spodosols. The spodosols had a layer of mor humus of thickness varying from nil in some parts in the smaller facies of heath forest (SHF) to 35 cm in the taller facies (THF). The overall aim was to investigate the forest soil biota and its role in nutrient turnover by comparing the SHF, THF and LERF. Microbial biomass, soil respiration and nitrogen transformation rates were measured in the three forest types in both wet and dry seasons. Field and laboratory fertilization experiments were made to investigate potential limiting nutrients for microorganisms and plants. The role of fine roots in decomposition and litter animal colonization was assessed in litter bag studies. SHF soils have a small microbial population with no net nitrification in any season. THF soils showed a variable microbial population adapted to high acidity, which immobilises nitrogen during the wet season, but which allows a net release during the dry season. LERF showed the most diverse population which causes mineralization and nitrification in both seasons. A bioassay with nutrient addition showed that the low pH, and nitrogen and sulphur supply were likely to be limiting nitrogen dynamics in all forest types, but especially in THF and LERF. The ingrowth bags showed that despite the lower values of fine root growth in the SHF (particularly when the white sand of the spodosol was used as the substrate), the roots showed in all plots an increased production with added calcium as carbonate or sulphate. In the decomposition bioassay to evaluate the role of roots in the nutrient turnover it was shown that in all forest types there was no effect of roots on the mass loss of Clitoria leaves but there was a significant effect on concentrations of some nutrients. In general, roots contributed to the accumulation of aluminium and iron and to a faster release and uptake of calcium, magnesium and zinc. A survey of the mycorrhizal associations in all forest types showed that both VAM and ECM fungi with some unknown VAM fungal species are common. VAM and ECM adaptation to low pH and high phenolic compounds in the soils may be important in the maintenance of these ecosystems.
30
Romell, Eva. "Artificial canopy gaps and the establishment of planted dipterocarp seedlings in Macaranga spp. dominated secondary tropical rain forests of Sabah, Borneo /." Umeå : Dept. of Forest Ecology and Management, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/10322511.pdf.
Full text
31
Samsoedin, Ismayadi. "Biodiversity and sustainability in the Bulungan Research Forest, East Kalimantan, Indonesia : the response of plant species to logging." Thesis, University of Stirling, 2007. http://hdl.handle.net/1893/224.
Full textAbstract:
This study reports forest structure, regeneration and the soil properties from unlogged and logged forest in the Bulungan Research Forest, Malinau District, East Kalimantan, Indonesia. Four sites were compared by using four 1-ha replicate plots in each of primary forest (PF), 5, 10 and 30-yr old logged forest (LF-5, LF-10, LF- 30). The tree species composition differ among forest types, as it was shown that the mean value of similarity indices for all pairs were 0.215 (for the Jaccard index) and 0.353 (for the Sorensen index). The low values for similarities among forest types were most probably caused by low numbers of species shared between each forest type. Both correlation values, r = 0.023 for Jaccard index and r = 0.031 for Sorensen index, showed no strong correlation between the similarity index (C) and the distance between forest types. This supports the use of a chronosequence approach. A total of 914 tree species with ³ 10 cm dbh were recorded from 223 genera and 65 families. There were no significant differences in mean species numbers (166 – 180/ha) among treatments. Mean density of species was lower in LF-5 and LF-10 (501/ha) than in PF or LF-30 (605/ha and 577/ha); similarly to mean basal area (LF-5, 28.5 m2/ha; LF-10, 32.6 m2/ha) vs. PF (45.8 m2/ha) and LF-30 (46.9 m2/ha). Dead wood on the forest floor was significantly higher in LF-10 (75 m3/ha) than in the other treatments. Seedlings (< 2 cm dbh) of 1,022 species were recorded from 408 genera and 111 families. The mean number of tree seedling species ranged between 170-206; the mean density of seedlings was about two-fold lower in LF-10 (2790/ha) than in the other treatments. Saplings (>2 – 9.9 cm dbh) of 802 species belonged to 241 genera and 65 families. There was a high variability in species richness across treatments (89 – 191/ha), but not in stem numbers. The Dipterocarpaceae family was dominant in all treatments, followed by the Euphorbiaceae. The soils were acidic, low in nutrients and had low to very low fertility. Both primary and logged forest areas are marginal or not suitable for sustained production of plantation crops. Logging caused soil compaction in LF-30. Although in terms of number of species and trees, amount of BA, number of saplings and seedlings LF-30 appeared to have satisfied prescriptions for a second harvest, ecologically the forest is far from mature. The Indonesian Selective Cutting and Replanting (TPTI) system may need to be revised to a 35 – 45 year cycle to ensure long-term forest productivity in terms of not only timber but other goods and ecosystem services, the value of which are never quantified in monetary terms, but can be higher than the timber revenue.
32
Sioh, Maureen Kim Lian. "Fractured reflections : rainforests, plantations and the Malaysian nation-state." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/NQ48715.pdf.
Full text
33
Cole, Lydia Eve Spencer. "Disturbance, recovery and resilience in tropical forests : a focus on the coastal peat swamp forests of Malaysian Borneo." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:a135aff3-ea84-4766-8046-b3bb4ce31275.
Full textAbstract:
Tropical forests have existed for up to one hundred million years, and today provide many ecosystem services vital for human well-being. They also harbour great biodiversity, which, in addition to its intrinsic value, plays a key role in the functioning of these ecosystems. Despite their local to global significance, there are still many knowledge gaps concerning the dynamic processes that govern the functioning of tropical forests. Rapid rates of deforestation and landscape conversion, predominantly for logging and industrial agriculture, are limiting the time and opportunity available to collect the information needed to fill these gaps. This research aims to shed light on the long-term ecological functioning of tropical forests, specifically investigating the history of disturbance in these ecosystems and the response of forest vegetation to past perturbations. The carbon-rich tropical peat swamp forests found along the coast of Sarawak, Malaysian Borneo, are a central focus of this study. For these forests in particular, a large deficit of knowledge surrounding their history and unique ecological functioning is coupled with some of the highest conversion rates of all tropical forest ecosystems across the world. In this thesis, palaeoecological data has been used to reconstruct temporal variability in forest vegetation coincident with external perturbations in order to identify changes in the resilience of these ecosystems through time, via indicators such as slowing rates of recovery and reduced regeneration of forest vegetation. Results suggest that tropical forest ecosystems have, for the most part, shown resilience to natural disturbances in the past, ranging from instantaneous localised tree-fall to longer-term regional climatic change; but that recent anthropogenic disturbances, of novel forms and greater intensities, are jeopardizing the potential for forest recovery and thus compromising ecosystem resilience. These findings enhance our understanding of the ecology of tropical peat swamp forests, and tropical forests more broadly. They also provide a context for contemporary tropical forest management, allowing for predictions on future responses to disturbance and enabling more ecologically sustainable landscape planning.
34
Paredes, Alvarado Angela [Verfasser]. "Assessing Utilization of Lesser Known Tree Species in Secondary Tropical Semi-Deciduous Forests of Colombia : A Contribution to Ecosystem Rehabilitation and Sustainable Forest Management / Angela Paredes Alvarado." Aachen : Shaker, 2013. http://d-nb.info/105157370X/34.
Full text
35
Maniatis, Danae. "Methodologies to ensure aboveground biomass in the Congo Basin Forest in a UNFCCC REDD+ context." Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.669953.
Full text
36
Manzi, Maya. "Peasant adaptation to environmental change in the Peruvian Amazon : livelihood responses in an Amerindian and a non-Amerindian community." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=83193.
Full textAbstract:
One of the primary challenges facing researchers and practitioners in their efforts to address issues of poverty and environment is the need to deepen our understanding of the logic that guides local people's decisions over resource use, particularly among the rural poor whose livelihoods depend on fragile and dynamic environments. This study seeks to identify the set of factors that influences how rainforest people respond to abrupt natural disturbances and resource scarcity through changes in livelihood and resource management practices in two rural poor communities of the Peruvian Amazon. Data were gathered through in-depth survey interviews (n=95 households) between June and December 2003 in the Amerindian community of Arica Viejo (Ucayali River) and the mestizo (ribereno) community of Roca Fuerte (Maranon River). The results reveal that socioeconomic characteristics such as forest experience and knowledge, and access to agricultural land explain striking differences among households in livelihood responses to environmental change, particularly concerning resource use behavior, resilience to disturbance, and the propensity to adopt sustainable resource management strategies.
37
Attah, Alhassan. "A model for forest and product certification in Ghana : the perception and attitudes of forest enterprises in Ghana." Thesis, Bucks New University, 2011. http://bucks.collections.crest.ac.uk/10085/.
Full textAbstract:
Forest and product certification was initially promoted as a means of enhancing sustainable management of forests in the tropics. However after almost two decades, there is still very little evidence of certified timber products originating from tropical countries. A number of approaches have been suggested to enhance the growth of forest certification in the tropics. These approaches such as that of the Forest Stewardship Council, Global Forest Trade Network of the World Wide Fund for Nature (WWF), Sustainable Forest Initiative and various private sector initiatives have all failed to facilitate forest certification. Therefore to enhance the development of forest certification in Ghana, the research work amongst others, draws on experiences in certification from other sectors such as cocoa, fisheries, tourism and oil palm to develop a model for promoting forest certification in Ghana. The research work uses elements identified in the literature review in developing a questionnaire for the survey of timber firms in Ghana. The research work identified stakeholder consultations, legal framework, resource rights, and the regulation of the domestic market as key elements for promoting forest certification in Ghana. The research recommends a phased approach to promoting forest certification with the first phase being verification of legality that adopts the European Union Forest Law Enforcement, Governance and Trade (FLEGT) and the Voluntary Partnership Agreement (VPA) initiative. The study identifies this approach not only as a means of reducing cost to the private sector in pursuing forest certification but a means of drawing on support measures to enhance the regulation of the domestic market; a key component for promoting forest certification. The report argues that it is only through a well regulated domestic market can tropical timber producing countries achieve sustainable forest management and hence forest certification. The domestic market is therefore seen as a strong means of promoting certification since it will be internalised in the producing countries. None of the research on certification has so far identified the domestic market as a key factor to promoting forest certification and the research work argues that the slow pace of certification has been the lack of demand for certified products on the domestic market. Developing the domestic market is therefore seen as a key policy instrument for promoting the uptake of forest certification in Ghana and the tropics in general.
38
Reis, Cristiano Rodrigues. "Mapeamento das restri??es operacionais e ambientais numa ?rea de Floresta Amaz?nica por meio do escaneamento laser aerotransportado." UFVJM, 2018. http://acervo.ufvjm.edu.br/jspui/handle/1/1789.
Full textAbstract:
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-08-20T13:19:07Z
No. of bitstreams: 2
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
cristiano_rodrigues_reis.pdf: 10913876 bytes, checksum: cc00db992e7afd3cffdad2079937fbce (MD5)Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-10-05T19:41:19Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) cristiano_rodrigues_reis.pdf: 10913876 bytes, checksum: cc00db992e7afd3cffdad2079937fbce (MD5)
Made available in DSpace on 2018-10-05T19:41:19Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) cristiano_rodrigues_reis.pdf: 10913876 bytes, checksum: cc00db992e7afd3cffdad2079937fbce (MD5) Previous issue date: 2018
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG)
Como defendido na explora??o de impacto reduzido, o planejamento ? fundamental para o manejo sustent?vel de florestas tropicais. Novas tecnologias, como o LiDAR, t?m permitido a constru??o de mapas e obten??o de estimativas que auxiliam tanto no planejamento quanto nas etapas de explora??o e monitoramento do impacto. Com o intuito de reunir os diversos produtos do escaneamento laser aerotransportado (ALS) dispersos na literatura e ?teis no manejo florestal, o objetivo deste trabalho foi apresentar uma sequ?ncia metodol?gica para determinar e monitorar as restri??es ambientais e operacionais em uma ?rea sob manejo na Amaz?nia. A ?rea de estudo encontra-se na fazenda Cauaxi, munic?pio de Paragominas, estado do Par?. Foram sobrevoados 1214 hectares de Floresta Amaz?nica submetidas a manejo de impacto reduzido. Foram gerados os modelos digitais de terreno (MDT), hidrol?gicos e topogr?ficos. A vegeta??o foi mapeada por meio dos modelos de densidade relativa (MDR), de biomassa, de localiza??o de ?rvores dominantes e codominantes, de clareiras e gerado o mapa da infraestrutura existente. Por fim, a estrutura vertical da floresta foi analisada pela descri??o do perfil vertical do dossel. A resolu??o do MDT foi de 1 metro e foi poss?vel observar a varia??o da eleva??o local e os divisores de ?gua. A densidade de drenagem foi de 1,7 km/km? e as ?reas de preserva??o permanente (APP) de cursos d??gua e nascentes somaram 137,7 ha. Mapas pouco utilizados como os de microbacias e dist?ncias vertical e horizontal poderiam ser considerados na divis?o da ?rea em unidades de produ??o anual e na delimita??o de APP, respectivamente. A declividade variou de 0 a 30?, n?o apresentando APP por declividade, caracter?stica de um relevo predominantemente suave ondulado. As ?reas com restri??o ao trator skidder n?o ultrapassaram 1 km? e, as restritas aos caminh?es carregados somaram 1,9 km?. A densidade de estradas na ?rea foi de 23,42 m.ha-1 e o n?mero de p?tios por hectare foi de 0,04. A ?rea total impactada pela abertura de estradas, trilhas e p?tios foi de 30,77 hectares, correspondendo ? 2,54% da ?rea total. Foi poss?vel observar menores valores de biomassa nas unidades de produ??o anual j? exploradas. O mesmo ocorreu entre os valores de porcentagem de clareiras. O valor de biomassa m?dio, considerando pixels de 50 m?, foi de 35,5 kg. Os menores valores dos par?metros de forma e escala da fun??o Weibull para o sub-bosque mostraram rela??o com as ?reas impactadas pela abertura de infraestrutura, sendo uma alternativa ao MDR no monitoramento do impacto. J? o par?metro de escala para o estrato da copa teve rela??o com o modelo de m?ximo dossel, indicando a localiza??o das ?rvores emergentes. Foi poss?vel mapear de maneira precisa as ?reas com restri??es ambientais e operacionais a partir do ALS, bem como, obter outros produtos interessantes para o manejo florestal. Este trabalho apresentou um roteiro metodol?gico para a inser??o do ALS no planejamento de todas as etapas do manejo florestal.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018.
The reduced impact logging refers to the forest planning as a critical step to the sustainable tropical forest management. New technologies, such as LiDAR, have made possible to obtain maps and estimates which help on the planning, exploitation and impact monitoring phases. In order to gather the useful products of airborne laser scanning (ALS) in forest management, the objective of this work was to present a methodological sequence to determine and monitor the environmental and operational constraints in an area under management in the Amazon. The overflown area is located at the Cauaxi farm, municipality of Paragominas, state of Par?, Brazil. The ALS covered 1214 hectares of amazon forest submitted to reduced impact logging. Then, models such as digital terrain model (DTM), hydrological and topographic were extracted. Furthermore, the vegetation was mapped through models of relative density (MDR), biomass, localization of dominant and codominant trees, and clearing and map of the existing infrastructure. Finally, the forest vertical structure was analyzed by the description of the canopy height profile. The 1meter resolution DTM allowed to observe the variation of elevation and water dividers. The drainage density was 1.7 km/km? and the permanent preservation areas (PPA) related to water courses and springs comprised 137.7 ha. Underused maps such as micro-basins and vertical and horizontal distances could be considered in the division of the area into annual production units and in the PPA delimitation, respectively. The slope ranged from 0 to 30 ? and did not present PPA by slope, characteristic of a predominantly soft wavy relief. The areas restricted to the skidder tractor does not exceed 1 km?, and those restricted to loaded trucks generated a total of 1.9 km?. The density of roads inside the area was 23.42 m.ha-1 and the number of the storage yards per hectare was 0.04. The area impacted by the opening of roads, trails and yards was 30.77 hectares, corresponding to 2.54% of the total area. It was possible to observe lower values of biomass in the annual production units already exploited. The same occurred with the percentage values of clearings. The average biomass value considering pixels of 50 m? was 35.5 kg. The lower values of shape and scale parameters of the Weibull function for the understory were related to the areas impacted by the infrastructure opening. The maps obtained with the Weibull parameters for understory can be an alternative to the RDM on the impact monitoring. The canopy scale parameter was related to the tall canopy model, indicating the location of the emergent ones. It was possible to accurately map the areas with environmental and operational restrictions from the ALS, as well as obtaining other interesting products for forest management. This work presents a methodological guide for the insertion of ALS in the planning of all stages of forest management.
39
Tengö, Maria. "Management Practices for Dealing with Uncertainty and Change : Social-Ecological Systems in Tanzania and Madagascar." Doctoral thesis, Stockholms universitet, Institutionen för systemekologi, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-309.
Full textAbstract:
The development of human societies rests on functioning ecosystems. This thesis builds on integrated theories of linked social-ecological systems and complex adaptive systems to increase the understanding of how to strengthen the capacity of ecosystems to generate services that sustain human well-being. In this work, I analyze such capacity in human-dominated production ecosystems in Tanzania and Madagascar, and how this capacity is related to local management practices. Resilience of social-ecological systems refers to the capacity to buffer change, to re-organize following disruption, and for adaptation and learning. In Papers I and II, qualitative interview methods are used for mapping and analyses of management practices in the agroecosystem of the Mbulu highlands, Northern Tanzania. Practices such as soil and water conservation, maintenance of habitats for pollinators and predators of pests, intercropping, and landscape diversification, act to buffer food production in a variable environment and sustain underlying ecological processes. The practices are embedded in a decentralized but nested system of institutions, such as communal land rights and social networks, that can buffer for localized disturbances such as temporary droughts. Paper II compares these findings with practices in a farming system in Sweden, and suggests that similar mechanisms for dealing with uncertainty and change can exist in spite of different biophysical conditions. In Papers III and IV, interviews are combined with GIS tools and vegetation sampling to study characteristics and dynamics of the dry forests of Androy, southern Madagascar. Paper III reports on a previously underestimated capacity of the dry forest of southern Madagascar to regenerate, showing areas of regeneration roughly equal areas of degenerated forest (18 700 ha). The pattern of forest regeneration, degradation, and stable cover during the period 1986-2000 was related to the enforcement of customary property rights (Paper III). Paper IV reports on a network of locally protected forest patches in Androy that is embedded in a landscape managed for agricultural or livestock production and contributes to the generation of ecosystem services and ecosystem resilience at a landscape scale. Forest protection is secured by local taboos that provide a well-functioning and legitimate sanctioning system related to religious beliefs. In Paper V, two spatial modeling tools are used to assess the generation of two services, crop pollination and seed dispersal, by the protected forest patches in southern Androy. The functioning of these services is dependent on the spatial configuration of protected patches in the fragmented landscape and can be highly vulnerable to even small changes in landscape forest cover. In conclusion, many of the identified practices are found to make ecological sense in the context of complex systems and contribute to the resilience of social-ecological systems. The thesis illustrates that the capacity of human-dominated production ecosystems to sustain a flow of desired ecosystem services is strongly associated with local management practices and the governance system that they are embedded in, and that, contrary to what is often assumed, local management can and does add resilience for desired ecosystem services. These findings have substantial policy implications, as insufficient recognition of the dynamics of social-ecological interactions is likely to lead to failure of schemes for human development and biodiversity conservation.
40
Boyemba, Bosela Faustin. "Ecologie de Pericopsis elata (Harms) Van Meeuwen (Fabaceae), arbre de forêt tropicale africaine à répartition agrégée." Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209883.
Full textAbstract:
Pericopsis elata is an African forestry species commercialized under the vernacular names afrormosia or assamela. It is one of the principal species commonly exploited for timber in the Democratic Republic of Congo (DRC) and in a lesser extent in Cameroon and Congo. In view of its sustainable resource exploitation, the species is in centre of numerous polemics notably in the European Union. It is one of the rare commercialized species that produce wood, since 1992, as listed in the CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) annex II specifying that “the exploitation of afrormosia necessitate the deliverance and a prior presentation of exploitation permit”. The most important reserves of afrormosia are found in DRC. This doctoral thesis presents the ecology of this particular tree and its behaviour regarding forestry exploitation. It allows to inform the international organisms such as CITES as well as the national policy-makers on the vulnerability of afrormosia and to propose appropriate measures that can avoid future unsustainable/unregulated exploitation activities/Pericopsis elata est une espèce forestière africaine commercialisée sous les noms d’afrormosia ou d’assamela. Elle est une des principales espèces exploitées pour le bois d’œuvre en République Démocratique du Congo (RDC) et dans une moindre mesure au Cameroun et au Congo. Elle est au centre de nombreuses polémiques, notamment dans l’Union européenne, en ce qui concerne la durabilité de son exploitation. C’est une des rares espèces commerciales productrice de bois d’œuvre listée, depuis 1992, dans l’Annexe II de la CITES (Convention sur le commerce international des espèces en danger d’extinction) qui spécifie que « L'exportation d'un spécimen d'une espèce inscrite à l'Annexe II nécessite la délivrance et la présentation préalables d'un permis d'exportation ». Les plus grandes réserves d’afrormosia se trouvent en RDC. Cette thèse de doctorat porte sur l’écologie de cet arbre et sur son comportement vis-à-vis de l’exploitation forestière. Elle permet d’informer les organismes internationaux comme la CITES et les décideurs nationaux sur la vulnérabilité de l’afrormosia et de proposer des mesures à prendre pour que l’espèce ne soit pas menacée par une exploitation mal conduite et non réguléeDoctorat en Sciences
info:eu-repo/semantics/nonPublished
41
Ebaa-Atyi, Richard. "The potential contribution of a diameter class matrix model to predict growth of mixed tropical forests /." 1988. http://hdl.handle.net/1957/10374.
Full text
42
Trauemicht, Parker Clayton. "The Cultivation And Management Of Chamaedorea Palms In The Understory Of A Tropical Rain Forest In Mexico." Thesis, 2004. http://hdl.handle.net/10125/10407.
Full text
43
Hadley, Adam S. "Independent effects of habitat loss and fragmentation on pollination : tropical forest fragmentation alters hummingbird movements and pollination dynamics." Thesis, 2012. http://hdl.handle.net/1957/33775.
Full textAbstract:
A growing body of work reveals that animal-mediated pollination is negatively affected by anthropogenic disturbance. Landscape-scale disturbance results in two often inter-related processes: (1) habitat loss, and (2) disruptions of habitat configuration (i.e. fragmentation). Understanding the relative effects of such processes is critical in designing effective management strategies to limit pollination and pollinator decline. I reviewed existing published work from 1989 to 2009 and found that only six of 303 studies separated the effects of habitat loss from fragmentation. I provide a synthesis of the current landscape, behavioral, and pollination ecology literature in order to present preliminary multiple working hypotheses to explain how these two landscape processes might independently influence pollination dynamics (Chapter 2). Despite the potential importance of independent effects of habitat fragmentation, effects on pollination remain largely untested. Studies designed to disentangle the independent effects of habitat loss and fragmentation are essential for gaining insight into landscape-mediated pollination declines. I also found that the field of landscape pollination ecology could benefit from quantification of the matrix, landscape functional connectivity, and pollinator movement behavior.
To test the hypothesis that pollinator movement can be influenced by landscape configuration, I translocated radio-tagged hummingbirds across agricultural and forested landscapes near Las Cruces, Costa Rica (Chapter 3). I found return paths were on average more direct in forested than in agricultural landscapes. In addition, movement paths chosen in agricultural landscapes were more forested than the most direct route suggesting that hummingbirds avoided crossing open areas when possible.
To determine if differences in pollinator movement translated to differences in plant reproduction, I tested the relative importance of landscape composition versus configuration on the reproductive success of Heliconia tortuosa, a hummingbird-pollinated forest herb (Chapter 4). I used a stratified random sampling design to select sites across orthogonal gradients in patch size, amount of forest, and elevation. I tested four landscape change hypotheses (i.e., local, landscape composition, landscape fragmentation, and fragmentation threshold). I found that Heliconia reproduction supported both the local site and landscape fragmentation hypotheses. Seed set increased with increasing forest patch size independent of amount of forest in the surrounding landscape. I also found that increasing patch size positively influenced the relative abundance of pollinators. The observed differences in seed set likely resulted from differences in hummingbird movements (Chapter 3) and/or abundance under different landscape configurations.Graduation date: 2013
44
Alimov, Bobur S. "Effects of international trade and corruption on tropical deforestation." 2002. http://catalog.hathitrust.org/api/volumes/oclc/54939620.html.
Full text
45
Taylor, Benton Neil. "Tropical rainforests getting their fix: The ecological drivers and consequences of nitrogen-fixing trees in regenerating Costa Rican rainforests." Thesis, 2018. https://doi.org/10.7916/D8TF1DR5.
Full textAbstract:
Tropical rainforests have an unparalleled capacity to sequester carbon, harbor biodiversity, and cycle water and nutrients due to their high rates of primary production. The large biomass stocks and rapid regeneration rates of these forests are often attributed to ample soil nitrogen and quick recovery of the nitrogen cycle in tropical soils following disturbance. Symbiotic nitrogen-fixing trees, which are relatively abundant at tropical latitudes, have the greatest capacity to provide tropical rainforests with new nitrogen, yet the ecological drivers of tropical symbiotic nitrogen fixers and their effects on the forests they inhabit are not well understood. This dissertation consists of four chapters that examine the patterns, environmental controls, and ecological consequences of symbiotic nitrogen-fixing trees in regenerating and intact rainforests in the Caribbean lowlands of Costa Rica. In chapter 1, I use field sampling in a chronosequence of rainforest plots to show that symbiotic nitrogen fixation declines through succession despite increases in the basal area of nitrogen-fixing trees. Chapters 2 and 3 describe results from a controlled shadehouse experiment assessing the effects of light, soil nitrogen, and plant competition on nitrogen fixation rates and the growth and biomass allocation of nitrogen fixers and non-fixers. In chapter 2, I demonstrate that light regulates nitrogen fixation more strongly than soil nitrogen availability. This is a departure from the historical focus on soil nitrogen as the primary regulator of nitrogen fixation and has the potential to resolve longstanding paradoxes of tropical nitrogen cycling. In chapter 3, I show that nitrogen fixation provides some resistance to competitive effects from neighboring plants in nitrogen-limited conditions, and that nitrogen fixers in these conditions downregulate their fixation rates in the presence of a competitor. This chapter also demonstrates that nitrogen fixation does not represent a significant structural cost to the plant, as reduced root biomass of nitrogen fixers more than compensates for allocation to nodule production. Finally, in Chapter 4, I demonstrate that nitrogen-fixing trees in our chronosequence plots do not promote forest growth, as expected given their capacity to fertilize their neighbors, but rather inhibit forest growth because they are strong competitors. These chapters describe several unexpected findings – i.e. that light primarily drives nitrogen fixation and that nitrogen fixers slow forest growth – which provide new and important insight into the role that nitrogen-fixing trees play in the growth of Costa Rican rainforests.
46
Djomo, Njepang Adrien. "Ecological Management of Tropical forests: Implications for climate change and Carbon Fluxes." Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-B13F-5.
Full text
47
Brambach, Fabian. "Diversity, composition, and biogeography of trees in tropical mountain forests of Sulawesi, Indonesia." Doctoral thesis, 2019. http://hdl.handle.net/21.11130/00-1735-0000-0005-1289-C.
Full text
48
Ingram, Carrie Denise. "Managing natural tropical forests for income and diversity a model for mixed lowland dipterocarps /." 1995. http://catalog.hathitrust.org/api/volumes/oclc/33630192.html.
Full textAbstract:
Thesis (Ph. D.)--University of Wisconsin-Madison, 1995.eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 116-124).
49
Brühl, Carsten A. [Verfasser]. "Leaf litter ant communities in tropical lowland rain forests in Sabah, Malaysia : effects of forest disturbance and fragmentation / vorgelegt von Carsten A. Brühl." 2002. http://d-nb.info/965968359/34.
Full text
50
Sustache, Sustache José A. "Post-hurricane growth and recruitment of plant species used by birds in northern Puerto Rico /." 2004. http://grad.uprm.edu/tesis/sustachesustache.pdf.
Full text