Dissertations / Theses on the topic 'Forest surveys'
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1
Hart, Tim. "Stem profile equations for several commercially important timber species in Wisconsin /." Link to full text, 2009. http://epapers.uwsp.edu/thesis/2009/Hart.pdf.
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Thesis (M.S.)--University of Wisconsin--Stevens Point, 2009.Submitted in partial fulfillment of the requirements of the degree Master of Science in Natural Resources (Forestry), College of Natural Resources. Includes bibliographical references (leaves 82-87).
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Bender, John Richard. "Identifying structural differences in mixed mesophytic and northern hardwood forests on the Monongahela National Forest using remote sensing data." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=976.
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Thesis (M.A.)--West Virginia University, 1999.Title from document title page. Document formatted into pages; contains viii, 55 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references (p. 44-48).
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Brown, Ian K. "Wisconsin statewide urban forest assessment : development and implementation /." Link to full text, 2007. http://epapers.uwsp.edu/thesis/2007/Brown.pdf.
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Holmström, Hampus. "Data acquisition for forestry planning by remote sensing based sample plot imputation /." Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6086-7.pdf.
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Holmgren, Eva. "Forest commons in boreal Sweden : influences on forest condition, management and the local economy /." Umeå : Dept. of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/10124692.pdf.
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Kamwi, Jonathan Mutau. "The use of high-resolution satellite imagery in forest inventory : a case of Hans Kanyinga Community Forest - Namibia." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/650.
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Holmgren, Eva. "Forest commons in boreal Sweden aims and outcomes on forest condition and rural development /." Umeå : Dept. of Forest Resource Management, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200996.pdf.
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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.
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Costanzo, Angela J. "A quantitative survey of riparian forest structure along the Quebrada Grande in La Cangreja National Park, Costa Rica /." Thesis, Connect to this title online, 2006. http://www.ranchomastatal.com/docs2/php5pk7ty%5FRiparianForestStructure%5FCostanzo.pdf.
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Korpela, Ilkka. "Individual tree measurements by means of digital aerial photogrammetry." Helsinki : Finnish Forest Research Institute, Finnish Society of Forest Science, 2004. http://catalog.hathitrust.org/api/volumes/oclc/55872310.html.
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Larson, Jill E. "A floristic inventory of vascular plants of the Carson National Forest and vicinity, north-central New Mexico." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1594496631&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Grotefendt, Richard. "Accurate and cost-effective natural resource data from super large scale aerial photography /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/5454.
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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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Olvera, Vargas Miguel. "Spatio-temporal dynamics of neotropical high-altitude mixed oak forests in western Mexico." Thesis, University of Oxford, 2006. http://ora.ox.ac.uk/objects/uuid:0928df01-b4fc-4028-b9a4-f7a393d71489.
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This thesis contributes to the understanding of two of the most intriguing questions that forest ecologists have faced over recent decades: 1) how high diversity is maintained in species-rich ecosystems; and 2) what is the role of spatio-temporal environmental variation in structuring forest communities. The aims of the research were to ascertain how species composition varies both spatially and temporally and how changes in the vegetation can be understood in the context of species coexistence theories (niche versus neutral). A group of 38 sympatric species, including 9 species of Quercus, on which little ecological research has been undertaken, were used in this study. The data used in this project include eleven years of periodic remeasurements of permanent plots established in high-altitude oak forests in Mexico. Adult, sapling and seedling trees were studied as well as their environmental surrounding. Spatial and temporal variations in forest composition were analysed using multivariate statistical approaches. The results show that there are discrete communities in these mixed oak forests that correspond to specific environments. At a broad scale the study area can be classified into two floristic zones, a mesic zone characterised by associations that include Quercus candicans, Q. laurina and Q. castanea and; a xeric zone dominated by Q. crassipes. However of a finer scale of analysis important variation in composition was associated with different life stages of the trees, with adult trees showing much stronger environmental associations than seedlings and saplings. Successional pathways and rates vary at relatively fine scales. This may be as a result of dominance alternation between dominant canopy species. Micro-niche zonation processes caused by a high degree of environmental heterogeneity combined with individual species traits explain the coexistence of phylogenetically similar sympatric Quercus species. A hierarchy of processes, each acting at a different spatial and temporal scale, determines species diversity and coexistence. The overall findings support the idea that niche differentiation rather than chance events such as dispersal limitation, are more important in permitting species coexistence.
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Bleier, Mary F. "Use of prior distributions from aerial photographs in forest inventory." Thesis, Virginia Tech, 1986. http://hdl.handle.net/10919/41543.
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Bayesian estimates of gross cubic- foot volume per acre were computed for four stand types (plantation pine, natural pine. hardwood. and mixed wood stands) using aerial photo volume tables as the prior information source. Aerial photographs provided a reliable source of information even though most photographs were nearly five years old.
For a given level of precision within a particular stand, Bayesian methods reduced the required field sample size up to 50% using all or half of the prior information available. Those priors which utilized a regression or a regression/topographic correction in the estimation of photo heights required less field information for the given precision level than those priors which used uncorrected or topographic corrected photo heights.
In order to obtain meaningful gains in sample size reduction corrections to the estimated photo heights
should be made. Although the uncorrected prior produced generally less biased estimates. the reduction in sample size was not as large as that observed using other prior types. Greater gains were attributed to the better accuracy of the prior distribution.
Although Bayesian methods are biased, it appeared that these methods tempered severely biased prior distributions. In the hardwood stand for example, the average bias present in the photo volume data amounted to -140%. After combining the prior with the field sample, the greatest average bias was -50%.
Bayesian methods performed better than the traditional estimation methods in terms of precision. In
a one to one comparison. the Bayes standard error was consistently less than its non-Bayes counterpart. The one exception to this trend was the regression prior from the hardwood stand. The poor performance of the prior was due to the weak height regression correction equation.
Modal priors utilized were not subject to the extreme input values for prior distribution development as
their conservative empirical prior counterparts were. Less overall variation was observed 1n the estimated values. Under the conditions for mode selection set forth in this project, modal priors provided another good source of prior information.Master of Science
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Twongyirwe, Ronald. "Forests under threat? : changes in land use and forest cover in rural western Uganda." Thesis, University of Cambridge, 2015. https://www.repository.cam.ac.uk/handle/1810/252713.
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Deforestation and land use change are widespread in western Uganda. However, the spatial patterns and time-series of change and the reasons why it is occurring remain to be fully investigated. In this work a combination of satellite imagery and social surveys is used to quantify forest gains and loss over the last three decades in the region close to Lake Albert, whilst also providing an account of possible drivers of change. This area proves to be interesting as it covers regions with both formally protected areas (gazetted regions) and un-protected forest, the latter being largely under private ownership. Remote sensing data from the Landsat satellites were gathered for forest change detection, and were processed using standard remote sensing techniques, then quantified using GIS and regression methods. Fieldwork allowed these data to be ground truthed while gathering (quantitative) household surveys and (qualitative) key informant interviews. Quantitative surveys were analysed using Principal Components Analysis (PCA) and cluster analysis, and were compared qualitatively with the satellite analysis and stakeholder interviews. The results show that forest cover declined significantly outside gazetted areas at the expense of varying local?scale processes, although the protection of the gazetted forests was remarkably successful. In forest corridors outside gazetted regions, losses exceeded 90% (p<0.05). Survey data suggest that rural poor households were more likely to be situated in forested regions, and were more dependent on forest resources for their livelihoods. However, the drivers of change were spatially variable, with expansion of sugarcane farming being a likely driver in the northern areas, but small?scale agricultural expansion a significant factor in the more southern parts of the study region. While there is wide agreement within the data that the patterns of forest cover and land use changes are anthropogenically driven, more specific drivers are swamped by intricacies of the bio-physical and socio-economic preconditions that are inseparable in both space and time, although agricultural expansion and population growth were evident and pervasive. The analyses provide insights into complex anthropogenic processes at various spatial scales, and policy recommendations provided are widely applicable for developing countries struggling to conserve nature whilst boosting economic growth.
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Bailes, Wesley Wayne. "A comparison of basal area and merchantable height as auxiliary variables for double sampling with point sampling." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3385.
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Thesis (M.S.)--West Virginia University, 2004.Title from document title page. Document formatted into pages; contains xi, 116 p. : ill. (some col.), col. maps. Vita. Includes abstract. Includes bibliographical references (p. 55-56).
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Metzler, Jacob W. "Use of Multi-temporal IKONOS and LANDSAT ETM+ Satellite Imagery to Determine Forest Stand Conditions in Northern Maine." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/MetzlerJW2004.pdf.
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Bushman, Matthew M. "Plant species change in northern Wisconsin wet-mesic forest communities from 1952 to 2005 /." Link to full-text, 2006. http://epapers.uwsp.edu/thesis/2006/Bushman.pdf.
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Wang, Jingxin. "An integrated computer-based timber cruising system for Appalachian hardwoods." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4280.
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Thesis (M.S.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains xi, 79 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 56-59).
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Fiery, Michael Allen. "A form of two-phase sampling utilizing regression analysis." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4312.
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Thesis (M.S.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains iv, 81 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 32).
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Shortt, James S. "A comparison of forest growth and yield models for inventory updating." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-01102009-063919/.
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Zielewska-Büttner, Katarzyna [Verfasser]. "Deriving biodiversity-relevant forest structure parameters: The value of aerial imagery from state surveys." Freiburg : Universität, 2020. http://d-nb.info/1229349405/34.
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Cohen, Jonathan Morris. "Stakeholder attitudes toward forest management in southern Illinois : an application of photo-evaluation surveys /." Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1594480701&sid=13&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Vogt, Holger K. H. "An investigation into the feasibility of forest inventory by means of stereo satellite imagery employing digital photogrammetry technology." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51609.
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Thesis (MSc)--Stellenbosch University, 2000.ENGLISH ABSTRACT: The aim of the study was to extract elevation information (such as tree height) from stereo satellite imagery (IRS-I C), to scrutinise the performance of the DTM (Digital Terrain Model) tools as provided by the LH (LeicalHelava) Systems' softcopy system, and subsequently to perform a feasibility study on the application of a practically viable forest inventory design. A softcopy photogrammetry workstation (LH Systems DPW 770), IRS-I C stereo panchromatic satellite imagery, and digital aerial photography at a scale of 1:30000 (scanned at 15 micrometers) was used. The study was conducted over various sites in the Sabie area (province of Mpumalanga) in South Africa, where extensive man made forests with pine and eucalypts are to be found. The extraction of stand parameters such as tree height was performed manually, semi-automatically, and automatically. In addition, the compartment area was determined using a GIS tool. The Digital Surface Models (DSM), representing the canopy structure of the stands, was extracted from the IRS-I C imagery and validated through a comparison of the resulting contours with the corresponding contours generated by aerial photogrammetric methods. Due to the coarse spatial resolution of the IRS-IC imagery (5m) and the suboptimal BIH (BaselHeight) ratio (0.57), only objects featuring a height exceeding 20m could be manually measured with confidence. Furthermore, only the edges of the compartments proved to be suitable for the determination of tree heights (i.e. with a sufficiently large parallax difference and image contrast). The manual determination of tree heights in the IRS-I C imagery yielded accuracies of about 95% compared to the height values of the aerial photographs and the ground data. The application of image enhancement techniques had severe effects on the accuracy of the IRS-IC stereo model, resulting in deviations of about -57m from the 'true' value. It was observed that image matching was only a problem where features changed their appearance (e.g. clearfelled or burnt areas) during the acquisition period of the stereo pair of the satellite imagery. LH Systems' Adaptive Automatic Terrain Extraction (AATE) tool performed very well for the creation of digital terrain and surface models when using digital aerial photography with a high scanning rate. In contrast, the automatic creation of canopy surface models from various forest compartments did not yield any useful results when applied to IRS-l C imagery. AATE could not model the canopy structure properly. The coarse spatial resolution of the satellite imagery in conjunction with the sparse post spacing (20m) and matching errors are most likely to be responsible for this poor performance. Two-phase sampling and the Hugershoff method were chosen for automatically derived height values to be evaluated for possible application in forest inventory. Unfortunately, neither for the determination of the regression estimator for the first method, nor for the calculation of timber volume after application of the Hugershoff method could any useful result be obtained. This is mostly due to the fact that image matching errors and blunders (resulting in tree heights of -885m) were not properly accounted for in the terrain extraction software. However, the outcomes for the manual measurement of tree heights performed on the satellite imagery show that under optimal conditions accuracies can be achieved similar to those for the height determination in small scale aerial photographs, but at lower cost. The obtained height values can then be used for the calculation of timber volume according to Eichhorn's law. Keywords: AATE, blunders, digital photogrammetry, DPW770, forest inventory, Hugershoff IRS-l C, matching error, remote sensing, satellite imagery, two-phase sampling
AFRIKAANSE OPSOMMING: N GANGBAARHEIDSTIIDIE VIR BOSINVENTARIS MET BEHULP VAN STEREO SATELLIETBEELDE MET GEBRUIK VAN SAGTEKOPIE FOTOGRAMMETRIESETEGNOLOGIE: Die doel van hierdie studie was om elevasie inligting (soos boomhoogtes) uit stereo satellietbeelde (IRS-I C) te ontrek, en die DTM (Digitale Terrein Modelle) funksies van die LH Systems se sagtekopie sisteem te evalueer en 'n ondersoek in te stel na praktiese toepassing van die tegnologie in bosvoorraadopname. 'n Sagtekopie fotogrammetriese werkstasie (LH Systems DPW 770), IRS-I C stereo panchromatiese satellietwaarneming en digitale lugfotografie is gebruik. Die studie is uitgevoer oor verskeie areas in die Sabie omgewing (Mpumalanga, Suid-Afrika), waar daar ekstensiewe mensgemaakte woude voorkom met denne en Eucalyptus soorte. Die ekstraksie van opstandparameters soos boomhoogte is uitgevoer met die hand, as ook met semi-outomatiese en outomatiese metodes. Die digitale oppervlakmodelle (wat die kroondakstrukture van die opstande voorstel) was vanaf die IRS-I C beelde onttrek en gevalideer deur vergelyking van die resulterende kontoere met die korresponderende kontoere wat deur lugfotogrammetriese metodes gegenereer is. As gevolg van die growwe ruimtelike resolusie van die IRS-IC waarneming (Sm) en die suboptimale BIH verhouding (0.57) kan slegs voorwerpe met 'n hoogte van meer as 20m met vertroue met die hand gemeet word. Slegs die rande van die vakke is bruikbaar vir die berekening van boomhoogtes (d.w. s. met 'n voldoende paralaksverskil en 'n sterk beeldkontras ). Boomhoogtes wat met die hand bepaal is vanaf IRS-I C beelde is 95% akkuraat in vergelyking met die hoogtewaardes verkry vanaf die lugfoto's en die veldmetings. Die toepassing van beeldverbeteringstegnieke het duidelike invloede op die akkuraatheid van die IRS-IC stereomodel met afwykings van ongeveer -57m vanaf die "werklike" waardes. Daar is ook waargeneem dat beeldooreenstemming slegs 'n probleem is waar terreinvorme se voorkoms verander het (weens afkappings of brande) gedurende die verkrygingsperiode waarin die stereo paar van die satellietbeelde verkry is. LH Systems se Aanpassende Outomatiese Terrein Onttrekkings (Adaptive Automatic Terrain Extraction - AATE) instrument het goed gevaar tydens die gebruik van digitale lugfotografie met Inhoë skanderingstempo. In kontras hiermee het die outomatiese skepping van kroondakoppervlakmodelle van verskeie plantasievakke geen nuttige resultate gelewer wanneer dit op IRS-I C beelde toegepas is nie. Die growwe ruimtelike resolusie van die satellietbeelde tesame met die wye paalspasïering (20m) en passingsfoute is waarskynlik vir hierdie swak resultate verantwoordelik. Twee-fase proefueming en die Hugershoff metode was gebruik vir die bepaling van outomaties afgeleide hoogtewaardes vir evaluering van moonlike toepassing in bosvoorraadopnames. Geen bruikbare resultate kon verkry word vir die vasstelling van die regressieskatter vir die eersgenoemde metode of vir die berekening van die houtvolume volgens die Hugershoff metode nie. Dit is meestal as gevolg van beeld-- ooreenkomsfoute en flaters, (wat tot boomhoogtes van -885m gelei het) wat nie voldoende in ag geneem word in die terreinekstraksie sagteware nie. Die resultate vir die handgemete ('manual') boomhoogtebepaling wat uitgevoer is op die satellietbeelde (op die sagtekopie werkstasie DPW 770), toon dat akkuraathede soortgelyk aan daardie vir hoogte bepaal op klein-skaal lugfotos onder optimale toestande verkry kan word, maar goedkoper. Die hoogtewaardes wat verkry is kan gebruik word vir die berekening van houtvolume volgens die wet van Eichhorn. Sleutelwoorde: AATE, afstandswaarneming, bosvoorraadopnames, digitale fotogrammetrie, DPW770, flaters, Hugershoff, IRS-! C, satellietbeelde, twee-fase proefueming
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Dessie, Gessesse. "Forest decline in South Central Ethiopia : Extent, history and process." Doctoral thesis, Stockholm : Department of Physical Geography and Quaternary Geology, Stockholm University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6840.
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Saoudi, Abdelhamid. "Utilisation des rapports radiométriques de bandes spectrales dans la discrimination des essences forestières par vidéographie aérienne multibande (vam) /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1997. http://theses.uqac.ca.
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Wallerman, Jörgen. "Remote sensing aided spatial prediction of forest stem volume /." Umeå : Dept. of Forest Resource Management and Geomatics, 2003. http://epsilon.slu.se/s271.pdf.
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Busse, Nielsen Anders. "Understanding and communicating forest stand structures : lifting barriers for nature-based forest management." Hørsholm : Forest & Landscape, 2006. http://www.sl.kvl.dk/upload/flr36.pdf.
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Jodry, Réal. "La télédétection multibande aéroportée MEIS II et DAEDALUS MSS appliquée à la cartographie forestière de la station Simoncouche /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1996. http://theses.uqac.ca.
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Lima, Natália da Silva 1989. "Amostras virtuais no monitoramento da produção florestal /." Botucatu, 2018. http://hdl.handle.net/11449/153248.
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Orientador: Célia Regina Lopes ZimbackCoorientador: Diego Augusto de Camps Moraes
Banca: Luis Gustavo Frediani Lessa
Banca: Osmar Delmanto Junior
Resumo: A elevada produtividade do eucalipto ocasiona a necessidade do domínio de técnicas e ferramentas precisas acerca dos povoamentos florestais, como o inventário florestal, procedimento fundamental para o monitoramento da produção que permite o conhecimento do máximo potencial das florestas, além disso, é essencial para o planejamento de atividades de corte, colheita e suprimento de madeira. As técnicas convencionais para o levantamento da produção florestal utilizam-se de métodos tradicionais de estatística (estatística clássica), considerando apenas a adoção de valores médios para a tomada de decisões, não explorando as correlações espaciais que possam existir entre as parcelas amostrais. Então, um tipo de interpolador geoestatístico que permite definir a estrutura de dependência espacial dos dados é a krigagem, que juntamente com a metodologia de amostras virtuais, pode-se tornar uma alternativa viável para obtenção de um variograma com modelagem aceitável. Desta forma, o objetivo geral deste estudo foi empregar a metodologia de amostras virtuais no planejamento da malha amostral do inventário florestal, a fim de possibilitar a determinação de um número de parcelas que possam ser estabelecidas na área para obtenção de produtividade, sem que haja perda de precisão ou aumento de custos. A área de estudo abrange uma área plantada de 287,66 ha, pertencente a empresa Eucatex S/A, localizada em Itatinga, no estado de São Paulo. Os dados dendrométricos de volume (m³.ha-1) foram obti... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The high productivity of eucalyptus trees makes it necessary to master accurate techniques and tools for forest, such as the forest inventory, a fundamental procedure for monitoring production that allows the knowledge of the maximum potential of forests, and is essential for planning of harvesting and supply of timber. Conventional techniques for surveying forest production use traditional statistical methods (classical statistics), considering only the adoption of average values for decision making, not exploring the spatial correlations that may exist between the sample plots. So, a kind of geostatistical interpolator that allows defining the structure of spatial dependence of data is kriging, which together with the methodology of virtual samples, can become a viable alternative to obtain a variogram with acceptable modeling. In this way, the aim of this study was to use the methodology of virtual samples in the planning of the sampling of the forest inventory, in order to allow the determination of a number of parcels that can be established in the area to obtain productivity, without losing accuracy or increasing costs. The study area covers a planted area of 287.66 ha, belonging to Eucatex S / A, located in Itatinga, in the state of São Paulo. The volume dendrometric data (m³.ha-1) were obtained through inventories carried out by the company and were estimated in 32 permanent rectangular plots for continuous forest inventories (CFI) and 32 permanent rectangular plots plus 66 temporary plots for the pre-cut inventory (PCI). The following steps were performed with the CFI data for spatialization of the original data in the ArcGIS program: application of an univariate statistic on the variable volume. ha-1; generation of the experimental variogram; variogram adjustment; validation of the theoretical model; application of kriging; generation of productivity maps year by year. Subsequently ...
Mestre
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Lane, Karl. "The feasibility of using remote sensing and field-based checks to monitor the impact caused by collection of wood in the Eastern Cape/Ciskei forest and thicket formations." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/21929.
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Bibliography: pages 71-83.A variety of studies have shown the problems of energy supply faced by low-income communities in southern Africa. Most of these communities are dependent upon indigenous fuelwood supplies. In addition, many of these communities use indigenous wood for construction. This largely uncontrolled utilisation imposes severe threats on woody vegetation communities. The Eastern Cape/Ciskei region is an area where energy supply problems are particularly severe and impacts on woody vegetation correspondingly severe. This study aimed to investigate the feasibility of using remote sensing techniques to monitor the the impact caused by collection of wood in the Eastern Cape/Ciskei forest and thicket communities. A variety of remote sensing techniques for landcover analysis were investigated. In all cases, visual interpretation was used because it is considerably cheaper and demands less technical expertise than would computer processing. In addition, many studies have shown visual interpretation to be superior. Maps were drawn from multitemporal aerial photograph sequences and from Landsat and SPOT satellite images. These maps showed that there has been relatively little change in area of woody vegetation in the study area since 1956. However, field studies showed that vegetation community structure had been degraded as a result of intense and sustained human impact. This qualitative decline also reflected a decline in usefulness of the woody vegetation of the area to local communities. This substantial degradation was not visible on any of the remote sensing imageries. This emphasises that field-based checks to monitor human impacts on forest and thicket formations are essential. Strategies for reducing the dependence of low-income communities on indigenous vegetation for energy supplies and constructional timber have been reviewed from the literature and these are descibed in Appendix 1. Most successful strategies in other parts of the world have been the result of a national commitment to tree planting, recognition of a multiplicity of constraints and the voluntary involvement of the communities the strategies are intended to assist.
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Maphiri, Stella. "Forest biomass energy use and perceptions on tree planting and community woodlots in households of two rural communities in Keiskammahoek, Eastern Cape, South Africa." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1503.
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Thesis (MScFor (Forest and Wood Science))--University of Stellenbosch, 2009.ENGLISH ABSTRACT: Access to secure energy supplies is widely acknowledged as a critical foundation for sustainable development. Rural households are highly dependent on forest resources for their livelihoods including energy needs. Fuelwood is a non-timber forest product (NTFP) that accounts for one of the main uses of forests and woodlands. Despite substantial household electrification programmes in South Africa, the use of fuelwood as a source of energy continues. This study aimed to analyze fuelwood use patterns of two rural villages situated in Keiskammahoek in the Eastern Cape Province of South Africa in order to understand the perceptions of the community members regarding communal tree planting. The study was conducted in two rural villages, namely, Cata and Tshoxa. A total of 120 respondents from both villages were interviewed using semi-structured questionnaires to collect data on the use of fuelwood and evaluate their perception on tree planting. The study revealed that up to 77% of the people living in Keiskammahoek used fuelwood as a major source of energy and that women were the main collectors and users of fuelwood. In the rural Cata, food is cooked in three-legged pots over open fires while in Tshoxa food is mainly cooked over paraffin and electric stoves. The respondents from both villages did not have energy conservation measures in place and improved wood stoves have not been introduced in this region. The local community of Cata was also involved in tree planting on a community level, while both villages were also involved in tree planting at a household level. The study concluded that fuelwood was the most important product from the forests in both rural areas and natural forests were a valuable source of other NTFPs; most notably indigenous fruit products. In addition most of the fuelwood was used for cooking and heating purposes but that there was no deliberate use of energy efficient methods. On tree planting, the study showed that communities from both rural villages have an interest in planting trees around their households; with preference for fruit and shade trees.
AFRIKAANSE OPSOMMING: Toegang tot betroubare energieverskaffing word algemeen erken as 'n uiters belangrike grondslag vir volhoubare ontwikkeling. Plattelandse huishoudings is hoogs afhanklik van bosbronne vir hul bestaan, met inbegrip van energiebehoeftes. Brandhout is 'n nie-hout bosproduk (NHBP) wat beskou word as een van die hoofgebruike van woude en boslande. Nieteenstaande wesenlike elektrifiseringsprogramme vir huishoudings in Suid-Afrika, duur die gebruik van brandhout as 'n bron van energie voort. Hierdie studie het beoog om die gebruikspatrone van brandhout van twee plattelandse dorpe in Keiskammahoek in die Oos-Kaapse Provinsie van Suid-Afrika te ontleed en om die begrip van die gemeenskap aangaande die gemeenskaplike plant van bome te verstaan. Die studie is in twee plattelandse dorpe, naamlik Cata en Tshoxa, uitgevoer. Onderhoude is gevoer met 'n totaal van 120 respondente van beide dorpe deur die gebruik van halfgestruktureerde vraelyste om gegewens oor die gebruik van brandhout in te samel en die respondente se begrip van die plant van bome te evalueer. Die studie het aan die lig gebring dat tot 77% van die mense wat in Keiskammahoek woon, brandhout as 'n hoofbron van energie gebruik en dat vrouens die hoofgaarders en gebruikers van brandhout is. In die landelike Cata word kos in driepootpotte op oop vure gekook terwyl kos in Tshoxa hoofsaaklik op paraffien- en elektriese stowe gekook word. Die respondente van beide dorpe het nie energiebesparingsmaatreëls in plek gehad nie en verbeterde houtstowe is nog nie in hierdie streek ingebring nie. Die plaaslike gemeenskap van Cata was ook betrokke by die plant van bome op 'n gemeenskapsvlak, terwyl beide dorpe ook betrokke was by die plant van bome op 'n huishoudelike vlak. Die studie het tot ’n gevolgtrekking gekom dat brandhout die belangrikste produk van die woude in beide plattelandse gebiede is en dat die natuurlike woude 'n belangrike bron van ander NHBP’s is; veral inheemse vrugteprodukte. Daarbenewens is meeste van die brandhout gebruik vir kook- en verhittingsdoeleindes, maar daar was geen doelbewuste gebruik van energiedoeltreffende metodes nie. Op die gebied van die plant van bome het die studie getoon dat die gemeenskappe van beide plattelandse dorpe belange het in die plant van bome rondom hulle huishoudings; met voorkeur aan vrugte- en skadubome.
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Ndlovu, Nomzamo Bonisiwe. "Quantifying indigenous forest change in Dukuduku from 1960 to 2008 using GIS and remote sensing techniques to support sustainable forest management planning." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85622.
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Thesis (MSc)--Stellenbosch University, 2013.ENGLISH ABSTRACT: This study aimed to understand how Dukuduku Forest in Kwa-Zulu Natal has changed from 1960 to 2008 and whether the change in political regimes, during and post apartheid eras might have contributed to changes in forest extent. To achieve the aims, the following analyses were made: - Qualitative and quantitative spatial analyses of forest change; - Analyses of the correspondence of change with political changes in the country; - Assessment of perception of people living in the Dukuduku forest area. The Dukuduku land cover was mapped from aerial photos using ArcGIS 9.3 to determine whether or not there has been a significant change in the area from 1960-2008, in response to resource use pressures and to come up with the strategic sustainable management plan from the results found. Five aerial photographs were used to determine the changes in land cover from the year: 1960, 1970, 1992, 2005 and 2008. The Land cover types were classified into four classes, Indigenous Forests, Plantation Forests, Water Bodies and Other (open areas, cultivated land, and all the human disturbed and transformed land). The percentage of cover per class was compared across the years to determine overall change in land cover and the rate of change per year was also calculated. The results from the study showed that: - Natural Forest increased by 11% (700 ha), at the rate of 20.56 hectares per year between 1960 and 1992, which is the apartheid era. Between 1992 and 2008, the democratic era, the forest decreased by 34.4% (2472.31ha), at the rate of 168 hectares per year. - The Dukuduku forest community gains resources (timber and grass for construction, art, firewood, medicinal plants, grazing of livestock and food) from the forest. The people are willing to contribute in protecting the forest only if the governing authorities would include them in decisions made, as the NFA demands Participatory Forest Management, but which does not currently exist in Dukuduku.
AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die verandering van die Dukuduku woud in Kwa-Zulu Natal vanaf 1960 tot 2008, en vernaamlik of die verandering in politieke regimes tydens en in die postapartheid eras tot verandering bygedra het in die woud se vorm. Om hierdie doelwitte te breik is die volgende analises gedoen: - Kwalitatiewe en kwantitatiewe ruimtelike analises van woudverandering; - Analises van die korrelasie tussen hierdie fisiese omgewingsverandering en politieke verandering in die land; - Analise van die persepsie van mense wat in die Dukuduku woudgebied woon. Die Dukuduku gronddekking is gekarteer met behulp van lugfotos, waarvoor ArcGIS 9.3 gebruik is om te bepaal of daar noemenswaardige verandering in die gebied plaasgevind het van 1960 tot 2008, in reaksie op hulpbrongebruike, en om ‘n volhoubare bestuursplan gestel voor wat op die bevindinge gebaseer is. Vyf lugfotos is gebruik om verandering in gronddekking te bepaal vir die jare: 1960, 1970, 1992, 2005 en 2008. Die Gronddekking tipes is geklassifiseer in vier klasse naamlik Inheemse Woude, Plantasiebosse, Waterliggame en Ander (oop gebiede, landerye en al die mens-versteurde en getransfomeerde gebiede). Die persentasie van elke dekkingsklas is oor die jare vergelyk om die verandering in algehele grond-dekking te bepaal, en die tempo van verandering is ook bepaal, asook die tempo van verandering. Die resultate van die studie wys dat: - Die natuurlike woud toegeneem het met 11% (700 ha), teen ‘n tempo van 20.56 hektaar per jaar tussen 1960 en 1992, tgedurende die apartheidsera. Tussen 1992 en 2008, die demokratiese era, het die woude verminder met 34.4% (2472.31 ha), teen ‘n tempo van 168 hektaar per jaar. - Die gemeenskap wat in die Dukuduku woud woon verkry hulpbronne van die woud (hout en gras vir konstruksie, kuns, brandhout, medisinale plante, weiding vir vee, en voedsel). Die mense is gewillig om by te dra tot beskerming van die woud indien die owerhede hulle sou betrek in besluite wat geneem word, veral omdat die nasionale Wet op Bosse voorsiening maak vir Deelnemende Bosbestuur, wat tans nie by Dukuduku gebeur nie.
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Zanga, Ambroise 1956. "Sampling efficiency evaluation in Emory oak woodlands of southeastern Arizona." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/291343.
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A forest inventory was made by a two-man team in the Emory oak (Quercus emoryi) woodlands, near the Huachuca Mountains, in southeastern Arizona. Two plot sizes, 1/10th, and 1/25th hectare, and three basal area factors, 2, 4 and 6 (square meters per hectare) were used. Tree tally time was recorded, but the travelling time between plots was not recorded. Total number of trees, total basal area, and total volume of trees per hectare were measured, summarized, and analyzed. Significant differences were noted between plot sampling and point sampling. Results suggested that with plot sampling, 1/25th hectare plot was more efficient than 1/10th hectare plot for all measures of forest densities. With point sampling, basal area factor 6 had the highest relative sampling efficiency in terms of trees per hectare. Basal area factor 2 had the highest relative sampling efficiency in terms of basal area and volume per hectare. From this information, more efficient forest inventories of the Emory oak woodlands can be designed.
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Helm, Amy Cimarolli. "The relationships between the forest fuels and vegetation of Richmond National Battlefield Park, Virginia." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-02132009-172549/.
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Kortenhoven, Aaron Peter. "Use of Gallery and Non-Gallery Forest by Ungulates Inhabiting the Loma Mountains Non-Hunting Forest Reserve, Sierra Leone, West Africa." Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_theses/206.
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This 11-month study examined rates of encountering dung pellet groups, dung piles and ungulates in gallery forests and non-gallery forests during diurnal surveys in the Loma Mountains Non-Hunting Forest Reserve (LMNHFR) in Sierra Leone, West Africa. These indices of relative abundance were then used to infer relative habitat use by the seven ungulate species on which data were collected. This study also examined the differences in rates of encountering duikers during nocturnal surveys with rates of encountering duikers during diurnal surveys to determine which time of day produces higher rates of encounter, and thereby a more accurate estimate of duiker abundance. The dung of four of the seven species, namely Cephalophus niger, Philantomba maxwelli, Tragelaphus scriptus, and Potamochoerus porcus is encountered at a higher rate in gallery forest than in non-gallery forest. Rates of encountering the dung of three species, C. silvicultor, C. dorsalis and Syncerus caffer nanus, do not differ between forest types. Rates of encountering four species, namely C. niger, P. maxwelli, T. scriptus, and C. silvicultor are higher in gallery forest than in non-gallery forest. Rates of encountering three species, namely C. dorsalis, S. caffer nanus, and P. porcus do not differ between forest types. Rates of encountering duikers ranged from three to six times higher during nocturnal surveys than during diurnal surveys for C. niger and P. maxwelli and 20 times higher for C. dorsalis. Survey timing did not affect the rate of encounter for C. silvicultor. Forest ungulates in the LMNHFR utilize gallery forests regularly. Possible reasons for the higher rates of encounter for six of the species in gallery forests compared with non-gallery forests are access to water, readily available browse resulting from annual fire damage on the periphery and interior of gallery forests, and easy access to cover for ungulates when foraging in adjacent grassland. Given the current rate of forest loss in West Africa, studies examining how forest mammals are able to persist in small forest fragments should be high priority for both government and conservation groups. The findings here give evidence that forest ungulates can and do use small areas of forest. Most importantly, the findings from this study show the global value of the LMNHFR for the conservation of large mammals endemic to the Upper Guinea Forests.
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Nguyen, Minh Hieu. "Deriving trip's modes and trip's purposes from GPS-based travel surveys." Thesis, Paris Est, 2020. https://these.univ-paris-est.fr/intranet/2020/2020PESC2006.
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Les données sur la mobilité jouent un rôle crucial dans la recherche sur le comportement des voyageurs et la prévision de la demande. Le recours exclusif aux techniques de collecte de données conventionnelles, à savoir entretien individuel, entretien téléphonique / Web / personnel assisté par ordinateur, sondage postal et courrier électronique présente de nombreux inconvénients, notamment une lourde charge pour les répondants, d’où un taux de réponse faible, description de la mobilité sur une seule journée par personne, manque de fiabilité en raison des limites de la mémoire humaine, coût élevé vue la nécessité d’un travail intensif, écart important entre les enquêtes périodiques sur la mobilité des ménages, sans oublier les difficultés à combiner et à harmoniser les données des enquêtes dans différents pays ou régions. L’utilisation maintenant sans contrainte du système de positionnement global (GPS) a ouvert de grandes possibilités pour améliorer la qualité de ces données. Les journaux relevés GPS sont objectifs, nombreux abondants, continus, détaillés et précis d’un point de vue spatio-temporel. Cependant, les informations de positionnement en elles-mêmes ne sont pas éligibles suffisantes pour l'analyse de la mobilité en raison de l'absence de caractéristiques des déplacements. Cette lacune a entraîné un développement substantiel de deux nouveaux domaines de recherche: l'imputation des modes de transport déplacement et du motif du voyage à partir des données GPS, respectivement. À l'heure actuelle, les téléphones intelligents sont les appareils privilégiés pour collecter les traces GPS et la description des déplacements correspondants. La détection du mode et du motif est une étape essentielle avant de procéder à une analyse du comportement de déplacement (choix du mode ou temps passé dans les activités, par exemple). En ce sens, les performances des algorithmes d'inférence du mode et du motif déterminent le potentiel de l'utilisation d'enquêtes basées sur GPS en tant que complément, voire même alternative complète aux techniques conventionnelles. Dans la littérature, il existe trois lacunes dans la recherche concernant les algorithmes d'imputation et pour les enquêtes assistées par GPS. La première provient du fait que, jusqu’à présent, les enquêtes GPS ont été menées essentiellement dans les zones urbaines des pays développés et parfois aussi en Chine. Par conséquent, l’utilisation du GPS dans les enquêtes sur la mobilité dans les villes des pays en développement reste à développer. La seconde et la troisième lacunes sont les conséquences de cette première limitation. La liste des modes de détection comprend la marche, le vélo, le transport en commun et la voiture, mais pas la moto, l’un des principaux moyens utilisés dans les pays émergents. Enfin, les imputations ont été mises en œuvre très fréquemment avec le support des Systèmes d’Information Géographique (SIG); Cependant, les données SIG ne sont pas partout disponibles et d’une qualité suffisante. L'absence de solutions raisonnables pour imputer les caractéristiques des déplacements à partir des données GPS sans l’apport d’un SIG constitue une lacune de la recherche. Cette thèse a pour objectif de rechercher des réponses aux trois questions susmentionnées en construisant à la fois des modèles d'inférence de mode et de motif. Deux ensembles de données ont été utilisés. Le premier a été collecté en Rhône-Alpes, en France, par un appareil dédié, tandis que le second a été rassemblé à Hanoï, au Vietnam, par smartphone. Sur la base des performances des classificateurs des recommandations visant à améliorer la qualité des enquêtes par GPS en général et pour les pays en développement en particulier ont été proposéesMobility data play a crucial role in travel behavior research and demand forecast. The complete reliance on conventional datum collection techniques, that is, face-to-face interview, computer-assisted telephone/web/personal interview, postal survey and email has a number of big drawbacks, including (1) high burden on respondents, thus high non-response rate, (2) inclusion of one-day data per person, (3) lack of reliability due to human memory limits and habit of rounding travel time, (4) high cost with intensive labor and (5) big time gap between periodic household travel surveys not to mention the difficulties in combining and harmonizing data of surveys in different regions or countries. The unlimited use of Global Positioning System (GPS) has opened up great opportunities for dealing with the problem of poor data. GPS logs are objective, numerous, continuous, detailed and accurate spatiotemporally. Yet, positioning information itself is not eligible for analysis due to the lack of trip characteristics. This deficiency has induced the substantial development of two new research fields that are involved in imputing transportation modes and trip purposes from GPS data, respectively. On-board devices were initially utilized to take advantage of electricity. Afterwards, lightweight, small and wearable personal devices have been developed to collect data at person level, which emphasized the need of detecting trip modes. Currently, smartphone is the most preferred devices to gather both logs and their corresponding so-called ground truth. Detections of mode and purpose are essential steps prior to do any travel behavior analyses (e.g. mode choice or time spending in activities). In this sense, the performances of mode and purpose inference algorithms determine the potential of employing GPS-based surveys as a supplement and even an entire alternative to conventional techniques. In the literature, there are three research gaps related to imputation algorithms and GPS-assisted surveys. The first is the great focus of investigations in well-structured urban areas of developed countries and occasionally in China. Therefore, the use of GPS in mobility surveys in cities of developing countries has been questionable. The others are consequences of the first limitation. Second, the list of mode detection encompasses walk, bike, transit and car but not motorcycle that is one of the main means in emerging countries. Last, purpose imputation has been implemented very frequently with the support of GIS data; however, GIS data are not available and good enough everywhere. Lack of reasonable solutions to derive purposes from GPS data without GIS data is a gap. This thesis aims at seeking answers to three mentioned-above existing questions by building both mode and purpose inference models. Two data sets were used. The first was collected in Rhone-Alpes, France by dedicated device whilst the second was gathered in Hanoi, Vietnam by smartphone. Based on prediction results, the discussions and recommendations for enhancing the quality of GPS-based surveys in general and for developing countries in particular have been proposed
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Mattsson, Mårten. "Markägare i Stockholms län och deras inställning till biodiversitet och skydd av mark /." Umeå : Institutionen för skoglig resurshushållning och geomatik, Sveriges lantbruksuniversitet, 2004. http://epsilon.slu.se/9717170.pdf.
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Sarı, Ragıp Avcı Mustafa. "Isparta ormanlarında zararlı lepidoptera ve hymenoptera türleriyle mücadelede biyoteknik yöntemlerin kullanımı /." Isparta : SDÜ Fen Bilimleri Enstitüsü, 2008. http://tez.sdu.edu.tr/Tezler/TF01158.pdf.
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Aldinger, Kyle Ray. "Playback surveys and breeding habitat characteristics of golden-winged warblers (Vermivora chrysoptera) on high-elevation pasturelands on the Monongahela National Forest, West Virginia." Morgantown, W. Va. : [West Virginia University Libraries], 2010. http://hdl.handle.net/10450/11269.
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Thesis (M.S.)--West Virginia University, 2010.Title from document title page. Document formatted into pages; contains ix, 99 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references.
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Turton, Rachael Heather. "The impact of the radiation balance on snowmelt in a sparse deciduous birch forest." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/29567.
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The representation of high-latitude surface processes and quantifying surface-climate feedbacks are some of the most serious shortcomings of present day Arctic land surface modelling. The energy balance of seasonally snow-covered sparse deciduous forests at high latitudes is poorly understood and inaccurately represented within hydrological and climate models. Snow cover plays an important role in wintertime fluxes of energy, water and carbon, controlling the length of the active growing season and hence the overall carbon balance of Arctic ecosystems. Snow cover is non-uniform and spatially variable, as wind redistributes snow from areas of exposed open tundra to sheltered areas within the forest, where a deeper snowpack develops. Low solar zenith angles, coupled with sparse deciduous leafless trees, cast shadows across the snow surface. The spatial distribution of canopy gaps determines the timing of direct radiation which penetrates down through the canopy to the snow surface. The forest canopy also excludes incoming longwave radiation and yet also emits longwave radiation to the snow surface. Consequently the forest canopy plays a key role in the radiation balance of sparse forests. To improve our knowledge of these complex processes, meteorological and field observations were taken in an area of highly heterogeneous birch Betula pubescens ssp. czerepanovii forest in Abisko, Sweden during the spring of 2008 and 2009. Detailed measurements of short and longwave radiation above and below the canopy, hemispherical photographs, tree temperatures and snow surveys were conducted to quantify the radiation balance of the sparse deciduous forest. An array of below canopy pyranometers found the mean canopy transmissivity to be 74 % in 2008 and 76 % in 2009. Hemispherical photographs taken at the pyranometer locations analysed with Gap Light Analyzer (GLA) showed reasonable agreement with a mean canopy transmissivity of 75 % in 2008 and 74 % in 2009. The canopy transmissivity was found to be independent of the diffuse fraction of radiation as the canopy is very sparse. A series of survey grids and transects were established to scale up from the below canopy pyranometers to the landscape scale. Hemispherical photographs analysed with GLA showed the sparse forest canopy had a mean transmissivity of 78 % and a mean LAI of 0.25, whereas the open tundra had a mean transmissivity of 97 % and a mean LAI of < 0.01. Snow surveys showed the sparse forest snow depth to vary between 0.34 and 0.55 m, whereas the snow depth in the open tundra varied between 0.12 and 0.18 m. Observations of canopy temperatures showed a strong influence of incident shortwave radiation warming the tree branches to temperatures up to 15 °C warmer than ambient air temperature on the south facing sides of the trees, and up to 6 °C on the north facing sides of the trees. To reproduce the observed radiation balance, two canopy models (Homogenous and Clumped) were developed. The Homogeneous canopy model assumes a single tree tile with a uniform sparse canopy. The Clumped canopy model assumes a tree and a grass tile, where the tree tile is permanently in shade from the canopy and the grass tile receives all the incoming radiation. These canopy models identified the need for a parameter that accounts for the spatial and temporal variation of the shaded gaps within the sparse forest. JULES (Joint UK Land Environment Simulator) is the community land surface model used in the UK Hadley Centre GCM suite. Modifications of the land-surface interactions were included in JULES to represent the shaded gaps within the sparse deciduous forest. New parameterisations were developed for the time-varying sunlit fractions of the gap (flit), the sky-view fraction (fv), and the longwave radiation emitted from the canopy (LWtree). These model developments were informed by field observations of the forest canopy and evaluated against the below canopy short and longwave radiation observed data sets. The JULES Shaded gap model output showed a strong positive relationship with the observations of below canopy shortwave and longwave radiation. The JULES Shaded gap model improves the ratio of observed to modelled short and longwave radiation on sunny days compared to the JULES model. The JULES Shaded gap model reduces the time to snow melt by 2 to 4 days compared to the JULES model, making the model output more aligned with in-situ observational data. This shortening of the modelled snow-season directly impacts on the simulated carbon and water balance regionally and has wider relevance at the pan-Arctic scale. When JULES Shaded Gap was evaluated on the global scale, it improved the modelled snowmass across large areas of sparse forest in northern Canada, Scandinavia and Northern Russia with respect to GlobSnow. The performance of the land surface-snow-vegetation interactions of JULES was improved by using the Shaded gap to model the radiation balance of sparse forests in climate-sensitive Arctic regions. Furthermore these observational data can be used to develop and evaluate high latitude land-surface processes and biogeochemical feedbacks in other earth system models.
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Lima, Gean Carlos Paia. "Comparação de diferentes métodos de cubagem de madeira de povoamento de Pinus taeda l. na região serrana de Santa Catarina." Universidade do Estado de Santa Catarina, 2015. http://tede.udesc.br/handle/handle/1950.
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Previous issue date: 2015-02-19The use of na appropriate volume calculation methods, wich can ensure better accuracy in determining individual volume of trees, is extremely importance in forest surveys, allows a smaller sampling intensity, given the stipulated erros with less time and labor cost. In this contexto, the aim of this study was to compare the volume calculation methods Smalian, Huber, Newton, Hohenadl (5 sections), Hohenadl )10 sections), FAO, Method sections, 19, Pressler and Sectional Standard, with the volume of trees determined by the water displacement method (Xylometer), wich is considered as true volume for Pinus taeda with age of 9, 13 and 20 years, in the municipalirty of Ponte Alta do Norte-SC. In total, were sampled 98 trees, all in according to the diferente methods, and clocked the time spent performing each method. After the trees were sectioned into logs of 3.10 meters, classified in assortment and applied the technique xylometer. Were fit the fifth-degree polynominal using the data obtained in each volume calculation method, checking what method provided the best fit and estimate the quantity in relation to xylometer. We used the completely randomized designs (CRD), with each tree set up a repetition of data and each cube of a treatment method. Bartlett s homogeneity rtest and analysis of variance (ANOVA) was applied to all ages, followed by the Tukey testa t 5% significance to compare the mean volumes and times. The analysis of variance showed significant diferentes between treatments for all ages, both the volume and for mearuting time. Independente of age, all volume calculation methods overestimated the volume of trees in relation to the real volume obtainde from the xylometer. For ages 9 and 13, volumes obtainde by volume calculation methods Huber, Pressler and Sectional Standard presented the lowest deviations compared to the xylometer with -0.08%; -0.43%, -0.97%; and 6,853%; -8.332%, -8.827% respectively. At age 20 years Hohenadl method (5 sections) showed the best precision (deviation of -1.98%) followed by Huber, Sectional Standard and Pressler, with deviations of -2.55, -2.59 and -3.03% respectively. By Tukey test, methods of sections 19, FAO, Smalian, Newton and Hohenadl (10 sections) differed its volumes compared to real volume to the age of 20 years. For the age of nine years only methods of sections 19, FAO, Smalian differed results about the real volume. To the age of 13 no method was statistically equal to the true volume. Methods FAO, Smalian and 19 sections were considered the worst methods to estimate the volume for all ages studied. Hohenadl (5 sections) was the volume calculation method of faster execution, differing from the other methods, Always with scaling of less than seconds. On the estimate of the volume of the fifth degree polynomial, the Sectional Standard method showed values to those obtained with the xylometer the three ages studied. Both Huber method as the Standard Sectional method had calculated volumes closer to the true volume determined by xylometer, and presente a time spent to achieve the very close of volume calculation methods that obtainde lowest times
O emprego de um método de cubagem adequado, que possa garantir melhor precisão na determinação do volume individual de árvores, é de suma importância nos levantamentos florestais, permite uma menor intensidade amostral, atendendo aos erros estipulados, com menor tempo e custo de trabalho. Nesse contexto, o objetivo do presente estudo foi comparar os métodos de cubagem de Smalian, Huber, Newton, Hohenadl (5 seções), Hohenadl (10 seções), FAO, Método relativo 19 seções, Pressler e Seccional Padrão, com o volume das árvores determinado por meio do método de deslocamento de água (Xilômetria), sendo este considerado como volume verdadeiro, para a espécie Pinus taeda com idades de 9, 13 e 20 anos, no município de Ponte Alta do Norte-SC. Foram cubadas 98 árvores de acordo com os diferentes métodos, sendo cronometrado o tempo gasto na execução de cada um. Após a cubagem as árvores foram seccionadas em toras de 3,10m, classificadas por sortimento e xilometradas. Foi ajustado o polinômio de quinto grau utilizando os dados obtidos em cada método de cubagem, verificando qual método proporciona o melhor ajuste e estimativa do volume em relação ao xilômetro. Foi empregado o Delineamento Inteiramente ao Acaso (DIC), sendo que cada árvore configurou uma repetição de dados e cada método de cubagem um tratamento. O teste de homogeneidade de Bartlett e análise de variância (ANOVA) foram aplicados para todas as idades, seguidos do teste de Tukey a 5% de significância para comparar as médias dos volumes e dos tempos. A análise de variância constatou diferença significativa entre os tratamentos de todas as idades, tanto para o volume como para o tempo de medição. Independente da idade, todos os métodos de cubagem superestimaram os volumes das árvores em relação ao volume verdadeiro obtido com a xilometria. Para as idades de nove e treze anos, os volumes obtidos pelos métodos de cubagem de Huber, Pressler e Seccional Padrão apresentaram os menores desvios comparado com o xilômetro, com -0,08%; -0,43% e -0,97%; e 6,853%; -8,332% e -8,827% respectivamente. Na idade 20 anos o método de Hohenadl (5 seções) apresentou a melhor precisão (desvio de -1,98%) seguido dos métodos de Huber, Seccional Padrão e Pressler, com desvios de -2,55, -2,59 e -3,03% respectivamente. Pelo teste de Tukey, os métodos de 19 seções, FAO, Smalian, Newton e Hohenadl (10 seções) diferiram seus volumes em relação ao volume verdadeiro para a idade de vinte anos. Para a idade de nove anos, apenas métodos de 19 seções, FAO, Smalian diferiram seus resultados em relação ao volume verdadeiro. Para a idade de 13 anos, nenhum método foi estatisticamente igual ao volume verdadeiro. Os Métodos da FAO, Smalian e 19 seções foram considerados os piores métodos na estimativa do volume para todas as idades estudadas. Hohenadl (5 seções) foi o método de cubagem de mais rápida execução, diferindo dos demais métodos, com tempo de cubagem sempre inferior a 60 segundos. Na estimava do volume pelo polinômio de quinto grau, o método Seccional Padrão apresentou valores mais próximos aos obtidos com a xilometria nas três idades em estudo. Tanto o método de Huber quanto o método Seccional Padrão apresentaram volumes calculados bem próximos ao volume verdadeiro determinado na xilometria, além de apresentar um tempo de medição bem próximo ao dos métodos que obtiveram os menores tempos de cubagem
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Gallagher, Sarah Louise. "Influence of habitat associations and distance from low-order streams on amphibian and reptile communities on public lands in east-central Mississippi." Master's thesis, Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-11092007-100145.
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O'Casey, Carol Elaine. "A floristic and vegetational analysis of the Mill Creek drainage area of the San Bernardino Mountains, California." CSUSB ScholarWorks, 1988. https://scholarworks.lib.csusb.edu/etd-project/323.
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Hull, Carter Dean. "Multicomponent chemical equilibrium modeling of the fluids and U-TH geochrnology of authigenic mineralization in geothermal systems /." View full-text version online through Crater Lake Digital Research Collection, 1990. http://craterlakelib.oit.edu/u?/craterlake,144.
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Thesis (Ph. D.)--University of Oregon, 1990.Typescript (photocopy). Presented to the Department of Geological Sciences and the Graduate School of the University of Oregon in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Includes bibliographical references (leaves 157-164).
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Fabian, Christopher J. "Application of a digital terrain model for forrest land classification and soil survey." Diss., Columbia, Mo. : University of Missouri-Columbia, 2004. http://hdl.handle.net/10355/4107.
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Thesis (M.S.) University of Missouri-Columbia, 2004.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (June 30, 2006). Vita. Includes bibliographical references.
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Subburayalu, Sakthi Kumaran. "Application of machine learning for soil survey updates a case study in southeastern Ohio /." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1199992659.
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Vande, Voort Amy M. "Habitat Characteristics and Occupancy Rates of Lewis's Woodpecker in Aspen." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/922.
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Lewis‘ woodpeckers (Melanerpes lewis) are generally associated with open ponderosa pine (Pinus ponderosa), open riparian, and burned pine habitats in the West; however, this species has recently been found to nest in aspen (Populus tremuloides) stands in Utah. This study describes the habitat characteristics of Lewis‘ woodpecker nest sites in aspen and investigates how well aspen stand characteristics predict Lewis‘ woodpecker occupancy. I surveyed for Lewis‘ woodpeckers at previously occupied nesting locations in aspen and took habitat measurements at nest sites. In addition, nest-centered Forest Inventory and Analysis (FIA)-type plots provided stand-level habitat characteristics. I used logistic regression to determine which stand-level habitat variables were associated with nest locations; significant variables were then used to select FIA plots in Utah that contained predicted suitable nesting habitat. Criteria used to select FIA plots were aspen type stands, percent canopy cover less than 46%, and average tree diameter at breast height greater than 27.9 cm (11 inches). I then conducted occupancy surveys at FIA plots predicted to contain “suitable” and “non-suitable” Lewis’ woodpecker habitat to field validate the predictive model. No predicted non-suitable plots (n=26) were occupied and only one predicted suitable plot (n=49) was occupied. My results indicated that Lewis’ woodpeckers are rare throughout Utah in aspen stands even though there seems to be abundant nesting habitat available. My results also indicated that variables measured by FIA do not, in isolation, provide sufficient capability to predict Lewis’ woodpecker nesting habitat or actual use, and that more data are needed to accurately predict Lewis’ woodpecker nesting habitat, such as distance to, age, and severity of fires.
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Winter, Cody R. "Perceptions Affecting Tree Valuation: An Analysis of Recently Sold and Leased Properties in Tampa, Florida." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/7110.
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The urban forest is a structure that is fluid in both species composition and how it is integrated in our cities and suburban areas. Much like the fluidity in its structure, the urban forest provides ecosystem services and disservices in many forms. These services and disservices can often come in the form of temperature regulation, lower crime rates, and even higher property values. The latter, which is associated with the economic value of trees, is a part of the hedonic pricing literature which suggests that there is a disparity in the value associated with trees to house prices. With the City of Tampa conducting its own hedonic pricing study, along with the presence of robust urban forest data, 2,000 residents of the city who had recently purchased or rented their home were mailed a questionnaire gauging how trees influenced their decision to live at their current residence and how they perceived the urban forest. Out of the 2,000 properties, 400 of the surveys were received resulting in a 20% return rate.
Five hypotheses were tested to determine how people’s perceptions affected the value they place on trees. It was hypothesized that home owners were more likely than renters to report tree disservices due to high maintenance costs, and potential damage. Additionally, it was hypothesized that homeowners would likely report more negative opinions of trees compared to renters. The analysis showed that tree drawbacks related to cost/maintenance and damage were reported by 43% and 45% of homeowners respectively. Likewise, 32% of renters reported cost/maintenance and 37% reported damage as their top drawbacks of trees. Although homeowners more frequently reported cost/maintenance and damage as drawbacks of trees, there was no significant statistical difference in opinion on trees at the .05 level. It was hypothesized that because neighborhood trees have less drawbacks such as property damage, residents would favor neighborhood trees more than trees on their property. Cross tabulating Likert statements with canopy cover did not reveal a preference for neighborhood trees above trees found directly on resident property. It was hypothesized that respondents living in homes with lower assessed values would express more negative opinions of trees such as cost and maintenance being reported as drawbacks. Cross tabulating sales price with the negative Likert statements concerning trees revealed that homes with higher assessed value reported more negative opinions of trees. It was hypothesized that different ethnic groups such as African Americans, Hispanic/Latinos, and White/Caucasians as well as residents of different affluence would report similar opinions and tree cover percentages with people from similar demographics. Despite the current literature suggesting differences in opinions, preferences, and canopy cover for different races/ethnicities, the analysis did not reveal a link between race/ethnicity and the availability of tree canopy or landscape preference. Finally, it was hypothesized that there would be a high correlation between residents’ purchases and/or rental decisions and the extent of canopy cover from trees originating on their property and/or in their neighborhood. For respondents who strongly agreed/agreed that trees influenced their rental/purchase decision there was a marginally higher canopy cover in the area surrounding their property than directly on their property. Additionally, there appeared to be no relationship with the level of agreement that trees influenced residents’ decision to rent/purchase and the amount of tree canopy on their property and in their neighborhood.
The conclusions of the study are that the opinions of trees in Tampa, FL are primarily positive among those in the sample population. In order to gain less biased results it is suggested that a door to door method be utilized in the future. It is also suggested that residents’ opinions are sampled after a severe storm to assess how hazardous conditions affect the overall opinions surrounding trees.