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Assessing Canopy Cover Requirements of Storm's Stork (Ciconia stormi) at Multiple ScalesBerdie, Ian Joseph 01 January 2008 (has links)
Much conservation work focuses on individual species, partly because of the perception that wildlife species are effective symbols for raising funds and drawing awareness to environmental causes. However, for species-based studies to aid conservation efforts, the biological and ecological needs of species need to be addressed in a way that informs decisions and provides concrete recommendations for land managers. This thesis addresses the forest cover needs of Ciconia stormi, a rare and understudied bird species that inhabits the islands of Borneo and Sumatra and parts of peninsular Malaysia. Levels of forest canopy cover associated with areas inhabited by Ciconia stormi are identified at multiple spatial resolutions using a 500m MODIS soft classification product, 30m Landsat data, and hemispherical photographs. Important threshold values of 75 percent tree cover was identified at the regional scale, and 85 percent at foraging sites. There has been severe forest disturbance in regions inhabited by Ciconia stormi between 1993 and 2004, indicating the species may be somewhat tolerant to disturbance. Areas having been logged at least 20 years before present average over 85 percent canopy cover and have few large gaps, indicating that these forests may be suitable habitat for the species.
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A 100-year retrospective and current carbon budget analysis for the Sooke Lake Watershed: Investigating the watershed-scale carbon implications of disturbance in the Capital Regional District’s water supply lands / One hundred-year retrospective and current carbon budget analysis for the Sooke Lake WatershedSmiley, Byron 01 May 2015 (has links)
Northern forest ecosystems play an important role in global carbon (C) cycling and are considered to be a net C sink for atmospheric C (IPCC, 2007; Pan, et al., 2011). Reservoir creation is a common cause of deforestation and when coupled with persistent harvest activity that occurs in forest ecosystems, these disturbance events can significantly affect the C budget of a watershed. To understand the effects of these factors on carbon cycling at a landscape level, an examination of forest harvest and reservoir creation was carried out in the watershed of the Sooke Lake Reservoir, the primary water supply for the Greater Victoria area in British Columbia. Covering the period between 1910 and 2012, a detailed disturbance and forest cover dataset was generated for the Sooke Lake Watershed (SLW) and used as input into a spatially-explicit version of the Carbon Budget Model of the Canadian Forest Sector 3 (CBM-CFS3). The model was modified to include export of C out of the forest system in the form of dissolved organic C (DOC) into streams. The fraction of decaying C exported through this mechanism was tuned in the model using DOC measurements from three catchments within the SLW. Site-specific growth and yield curves were also generated for watershed forest stand types, in part, by using LiDAR-derived site indices. C transfers associated with disturbances were adjusted to reflect the disturbance types that occurred during the 100-year study period.
Due to the removal of C resulting from wildfire, logging and residue burning, as well as deforestation disturbances, total ecosystem C stocks dropped from 700 metric tonnes of C per hectare (tC ha-1) in 1910 to their current (2012) level of ~550 tC ha-1 across the SLW. Assuming no change in management priorities and negligible effects of climate change, total ecosystem C stocks will not recover to 1910 levels until 2075. The cumulative effect of reservoir creation and expansion on the C budget resulted in 14 tC ha-1 less being sequestered (111,217 tC total) across the watershed by 2012. In contrast, sustained yield forestry within the Capital Regional District’s tenure accounts for a 93 tC ha-1 decrease by 2012, representing an impact six times greater than deforestation associated with reservoir creation. The proportionally greater impact of forestry activity is partly due to current C accounting rules (Intergovernmental Panel on Climate Change) that treats C removed from the forest in the form of Harvested Wood Products as C immediately released to the atmosphere as carbon dioxide. Cumulative DOC export to the Sooke Lake reservoir was ~30,660 tC by 2012, representing a substantial pathway for C leaving the forest ecosystem. However, more research is required to understand what fraction of terrestrially-derived DOC is sequestered long term in lake sediment. The results of this study will assist forest manager decision making on the appropriate management response to future forest disturbance patterns that could result from climate change and to improve climate change mitigation efforts. / Graduate / 0478 / 0425 / 0368 / byrons@uvic.ca
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Ecological Responses of Avian Species to Land Cover Metrics at the Landscape-Level and Across Broad Spatial ExtentDe Camargo, Rafael Xavier January 2018 (has links)
Human activities have transformed natural landscapes into human-dominated areas at unprecedented rates in the last centuries. Land cover transformation is associated with loss of natural habitat, thus a threat to biodiversity. Because habitat loss will likely continue in the future due to population growth and increase demand for natural resources, an important question in ecological studies is whether land cover features (i.e. amount, variety, shape, configuration) can be used as predictors to estimate species loss from habitat modification.
This thesis investigates the predictive ability of landscape features in predicting species distributions at the landscape level and across large regions. It tests several predictions from classic hypotheses such as the species-area relationship and habitat fragmentation, utilizing a macroecological approach. Response variables (e.g. species richness, species’ probability of occurrence) and independent variables (e.g. proportion of natural areas, metrics of fragmentation, temperature, etc.) are analysed in cell sizes of 25-900km2 covering large regions (e.g. southern Ontario, New York State). Bird species were chosen as the main biological model.
Most literature assumes that species richness should vary positively as a function of remaining natural area, following the well-known species–area relationship (i.e. classic SAR). Prior studies have shown that avian species richness has a peaked, rather than a monotonic increasing, relationship with the proportion of natural land cover in landscapes of southern Ontario. The first chapter of the thesis showed improvements in the predictive power of classic SARs by proposing the “Lost-habitat SAR”, which demonstrates that richness of open-habitat species can be predicted when we partition human-dominated land cover into an ‘‘available human-dominated’’ component and ‘‘lost’’ habitat (i.e. parts of the landscape that can no longer be utilized by any species).
The second chapter addresses a current contention in the literature about the effect of habitat fragmentation beyond habitat amount at the landscape level. Specifically, I tested the effect of fragmentation (e.g. number of patches) on both avian richness and the probability of occurrence (pocc) of individual species, after controlling for habitat amount in 991 landscapes, each 100-km2, in southern Ontario. The analysis showed that overall species richness responds primarily to habitat amount, and that the effect of habitat fragmentation, holding the total amount of habitat constant, is negligible. The probability of occurrence of a few bird species did relate negatively to the size, number and isolation of the patches within the landscape. We argue that the evidence is inconsistent with the hypothesis that reducing habitat fragmentation would be an effective conservation strategy for birds at the landscape level.
Chapter 3 tested the speculation in the climate change literature that habitat loss may impede the colonization or movement of species whose ranges are shifting northwards in response to climate. Using the same 100-km2 landscapes of southern Ontario, I examined individual bird species’ probability of occupancy as a function of the amount of remaining natural land cover for three groups of species: i) those whose northern range limit falls within the study area, ii) those whose southern range limit is in the study area, and iii) those whose ranges cover the entire study area. The results showed that the probability of occupancy of southern-edge species is a positive function of the amount of natural land cover (forest) in the landscape, while the probability of occupancy of northern-edge species is a negative function of natural land cover. Hence, I conclude that at southern range limits species faces the dual stresses of climatic warming and habitat conversion. Whereas, at northern (potentially expanding) range edges, partially disturbed landscapes are more readily occupied than undisturbed landscapes.
In the final chapter, I challenge widely accepted hypothesis that habitat loss causes biodiversity loss by testing whether conserving natural land cover would conserve species diversity. More specifically, I tested whether broad-extent relationships between avian species richness and natural land cover are independent of: 1) whether species distribution data come from systematic censuses (atlases) versus range maps, and 2) the grain size of the analysis in grid cells covering southern Ontario, CA, and New York State, US. My findings showed that over regional extents, range-map-based richness relates strongly to temperature, irrespective of spatial grain, and that censused species richness relates to temperature less strongly. Moreover, range-map richness is a negative function of the proportion of natural land cover, while realized richness is a peaked function. Therefore, I conclude that conserving natural land cover would not conserve species diversity in southern Ontario or in New York State, since greater natural cover does not imply higher richness. We argue that habitat loss has become a panchreston. It may be misguiding conservation biology strategies by focusing on a threat that is too general to be usefully predictive.
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Determination of priority areas for the re-establishment of the forest cover, based on the use of geotecnologies: Una waterched case study, Taubaté, SP / Determinação de áreas prioritárias para o restabelecimento da cobertura florestal apoiada no uso de geotecnologias: estudo de caso da bacia hidrográfica do rio Una em Taubaté, SPCelso de Souza Catelani 08 October 2007 (has links)
The determination of priority areas for the re-establishment of forest cover in watersheds is directly associated with probability of effective success in forestry project implementation. However, considering analysis complexity and the amount of spatial data necessary to accomplish that goal, state of the art technology tools capable of providing multi-criteria analysis to support decision make are necessary. This research was developed in an area of 476km that corresponds to the Una River basin in the municipality of Taubaté, SP. A multi-criteria analysis was based on continuous classification and paired comparisons using AHP (Analytical Hierarchy Process) techniques, available in the GIS package called SPRING v. 4.3.2 (Georeferenced Information Processing System). A map of priority areas for the reestablishment of forest cover in that watershed was obtained, and results revealed a large area (26.6% of the total watershed area) with extreme priority for forest cover re-establishment. This indicates the urgent need of environmental restoration in this basin. This indicates a strategy improving making decision process in the practical manner toward resource application only on priority areas. / A determinação de áreas prioritárias para o restabelecimento da cobertura florestal nativa em bacias hidrográficas se constitui numa ferramenta diretamente associada à necessidade de otimizar os parcos recursos eventualmente disponíveis, para se obter o sucesso efetivo na implantação de projetos dessa natureza. No entanto, para atender a essa finalidade, a complexidade no tratamento e o volume de dados ambientais espacializados necessários requerem um aparato tecnológico capaz de processar uma análise multicriterial como ferramenta de suporte à decisão, no estado da arte das geotecnologias aplicáveis. Nesse contexto, o presente trabalho desenvolvido para uma área de 476km correspondentes à área da Bacia Hidrográfica do Rio Una no município de Taubaté, SP, aborda uma análise multicriterial baseada na classificação contínua e na técnica de comparação pareada AHP (Analytical Hierarchy Process), incorporados ao SIG completo denominado SPRING v. 4.3.2 (Sistema de Processamento de Informações Georreferenciadas), para a obtenção de um mapa de áreas prioritárias para o restabelecimento da cobertura florestal nativa na bacia. Os resultados obtidos revelaram uma grande área, correspondente a 26,6% da área da bacia, classificada como Prioridade Extrema. Isso indica a necessidade de recuperação ambiental da bacia. Os resultados permitem de forma prática subsidiar a tomada de decisão na alocação de recursos e projetos dessa natureza nessas áreas prioritárias.
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Vývoj metod oceňování lesa v podmínkách ČR / Development of Forest Valuation Methods in the Czech RepublicAbsolonová, Jana January 2019 (has links)
The aim of this thesis was to define the issue of determining the administrative price and market value of forest in the Czech Republic. The thesis describes the evolution of methods of determining the price of forest in history since 1897. Furthermore, the thesis deals with the current problem of determining the market value of forest in the Czech Republic. The current situation is documented by a case study, which deals with the determination of the administrative price and market value. The study compares these two values. The final analysis is focused on recommendations of corrections of existing valuation regulations and method of market valuation of forest.
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Forest Cover and Economic Development : A cross-country study on the relationship between forest cover and economic development in South AmericaDalberg, Terry, Svensson, Felix January 2021 (has links)
Ongoing deforestation is an urgent, global issue with both direct and indirect impacts on a nation’s future development. This as change in forest cover and economic development provides an intuitive link between each other. Deforestation is driven by the expectations of economic return through exploitation of natural resources in search for economic development. The purpose of this paper is to investigate the relationship between change in forest cover and economic development in South America between 1991 and 2019. Even if deforestation is considered widely studied, it remains an empirical question how it relates to economic development. This study uses the framework of Environmental Kuznets Curve for Deforestation (EKCD), an economic theory which suggest that economic development has an inverted U-shaped relationship with deforestation. By using a fixed effect model, we find evidence of a U-shaped relationship between forest cover and income (GDP per capita). Our results indicate that a country’s forest cover decline as income raises until a turning point is reached, after which forest cover increases together with advancing economic development. Hence, provide empirical evidence of the existence of a U-shaped EKCD in South America. Furthermore, the study is conducted using average data and the turning point therefore is also an average for the continent
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The Transition of Farming Systems Causing Forest Degradation in Ratanakiri Province, Cambodia / カンボジア・ラタナキリ州における森林劣化を引き起こす農業システムの変遷Hor, Sanara 25 November 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第18668号 / 地環博第126号 / 新制||地環||26(附属図書館) / 31582 / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)教授 渡邉 紹裕, 准教授 西前 出, 准教授 橋本 禅 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
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The Effects of Heterogeneous Marijuana Policy Legalization in California on Surrounding EnvironmentsPrice, Gina A. 12 September 2022 (has links)
No description available.
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Optimum Forest Management through Investigating Land-cover Changes, Deforestation Drivers, Forest Structure and Local Livelihoods in Banmauk Township, Myanmar / ミャンマー、バンマウクにおける土地被覆変化、森林伐採要因、森林構造および地域住民の生計を通してみた最適な森林管理Aye, Tin Hnaung 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(農学) / 甲第24907号 / 農博第2570号 / 新制||農||1102(附属図書館) / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 柴田 昌三, 教授 松下 幸司, 教授 德地 直子 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
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The impact of forest on pest damage, pollinators and pollination services in an Ethiopian agricultural landscapeSamnegård, Ulrika January 2016 (has links)
The distribution of wild biodiversity in agroecosystems affect crop performance and yield in various ways. In this thesis I have studied the impact of wild biodiversity, in terms of trees and forest structures, on crop pests, pollinators and the pollination services provided in a heterogeneous landscape in southwestern Ethiopia. Coffee, Coffea arabica, is a forest shrub native to Ethiopia and is grown in most wooded areas in the landscape where I conducted my studies. Wild coffee is still found in remote parts of the forests in the landscape. For my first paper, I surveyed pest damage on coffee in coffee forest sites, where some sites were situated in continuous forest and some in isolated forest patches. I found the variation in pest damage frequency to mainly be among coffee plants within a site, rather than among sites, which indicates the importance of local processes. However, some pests were clearly connected to the forest habitat, such as the olive baboon. In my second study, I surveyed pollinators visiting coffee flowers across a gradient of shade-tree structures. I found the semi-wild honeybee to be the dominating flower visitor. The abundance of the honeybee was not related to shade-tree structures, but to amount of coffee flower resources in the site. On the other hand, other pollinators, which included other bee species and hoverflies, were positively affected by more shade trees in the site. In my third study I investigated how the forest cover affected local bee communities in the agricultural landscape. Moreover, I investigated if this relationship differed between the dry and rainy season. The distribution of food resources for bees changes between the seasons, which may affect the bees. Most trees, fruit trees and coffee, which are patchy resources, flowers in the dry season, whereas most herbs and annual crops, which are more evenly spread resources, flowers during the rainy season. I found a clear turnover in bee species composition between the dry and rainy season, with more mobile species in the dry season. Increased forest cover in the surrounding landscape had a positive impact on bee abundance and species richness. However, the impact did not change between seasons. In my fourth study I evaluated the pollination success and pollen limitation of a common oil crop in the landscape in relation to forest cover. I found severe pollen limitation across the landscape, which may be related to the observed low bee abundances. The pollen limitation was not related to surrounding forest cover. In conclusion, I have found the forest and wooded habitats to impact several mobile animals and pathogens in our study landscape, which in turn affect people. However, there is large complexity in nature and general relationships between forest structures and all crop related organisms may be unlikely to find. Various species are dependent on different resources, at different spatial scales and are interacting with several other species. To develop management strategies for increased pollination services, for reduced pest damage or for conservation in the landscape, more species-specific knowledge is needed. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>
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