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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Body weight estimation of Bovidae and Plio-Pleistocene faunal change, Turkana Basin, Kenya

Leakey, Louise Nicol January 2001 (has links)
No description available.
2

Microsatellite variability in four contemporary rhinoceros species : implications for conservation

Scott, Candace A. 08 July 2008 (has links)
Rhinoceroses are arguably the most endangered of all large mammal taxa. In order for ongoing conservation of this species to be successful, it is crucial to accurately characterize the remaining genetic diversity for all rhinoceros species. To do this, I optimized a standard suite of 24 taxon-specific rhinoceros microsatellite loci. These loci have the power to provide the most comprehensive estimate of comparative microsatellite genetic diversity within and among the four extant African and Asian rhinoceros genera. These loci were further used to evaluate the comparative influences of rhinoceros species versus microsatellite taxonomic origin as predictors of rhino microsatellite diversity, and finally to examine the evolutionary relationships between extant rhino taxa. The African black michaeli rhino subspecies had the highest level of microsatellite genetic variability of all available rhinos, while southern white and Indian rhinos were the least variable rhinos. These findings also suggested that species and taxonomic origin of microsatellite loci were both significant predictors of microsatellite heterozygosity in rhinoceroses. A weak association between the Sumatran and black rhinos was found with a DLR neighbour-joining tree. The standard loci were able to assign unique genotypes to all available rhinos as well as differentiate between all rhino species by correctly assigning individual rhinos back to their respective populations. / Thesis (Master, Biology) -- Queen's University, 2008-07-02 23:01:32.553
3

Large Mammal Movement: Differences in Primary and Branch Logging Road Use in Algonquin Provincial Park, Ontario

Roulston, Hillary Emma January 2013 (has links)
There is an expansive network of roads in Algonquin Provincial Park (APP) to facilitate forestry resource extraction. This leaves a research need for examining how the logging road network in APP affects the large mammals, and what local-level and landscape-level variables influence that use. Local-level data was collected directly at observation points, and landscape-level data was produced from ArcGIS for 40km2, 80km2, and 130km2 buffer areas. The objective of my study was to look at the use of primary and branch logging roads by five large mammal species in APP, and determine if landscape-level variables had an influence on the level of movement and utilization. The five species included moose, white-tailed deer, American black bear, eastern wolf and coyote. My null hypothesis (H0) states that there will be no difference in large mammal use between the primary and branch logging roads within APP and that local- and landscape-level variables will have no influence on them; my alternative hypothesis (H1) states that there will be less large mammal activity on the primary logging roads, more large mammal movement on the branch logging roads and local- and landscape-level variables will influence this use. Tracking was done by vehicle on six transects across the park for three repeated surveys where species identification and local-level variables were recorded. Landscape-level variables were acquired through GIS analysis in the lab. Based on the results from the local-level data, branch and primary logging road use differed in composition, though no significance was found between the use by large mammals for these two types of road. Through generalized linear models, specific combinations of landscape-level variables did influence large mammal movement on the primary and branch logging roads within three habitat range scales (130km2, 80km2, and 40km2). The most significance was seen at the buffer of 40km2 on the branch logging roads, with the variables road density (p < 0.01), percent forest cover (p = 0.04) and topographic ruggedness (p < 0.01) all having a strong impact on large mammal movement. The only significant findings for primary logging roads were also at the 40km2 scale with percent forest cover (p = 0.03) and percent water cover (p = 0.02) having an impact on large mammal movement. Overall, the landscape variables had greater influence on branch logging roads that may be explained by the quality of the surrounding habitat, as well as greater influence at smaller buffer scales. Further research and monitoring of the large mammals in APP is recommended to expand on this preliminary study. Greater understanding of the local- and landscape-level variables at differing habitat ranges will assist in understanding these large mammal movements and provide data to base logging road management on. As large mammals are wide-ranging species, my study informs APP that their logging road network does not seem to hinder the movements of this group of animals. Overall, the large mammals in APP did not have any significant difference in their use of primary and branch logging roads of APP. Further research has the potential to give greater understanding of the impacts of the logging road network on the five large mammal species studied in APP. There is also the potential for useful management strategies to emerge for large mammals in this park, and how to incorporate human activities within their habitat while maintaining sustainable populations.
4

Gregarious Behavior in Large Mammals: Modeling, Methodology, and Application

Morton, Thomas L. 01 May 1993 (has links)
Gregarious behavior of ungulates was considered in four ways. The first concern was W. D. Hamilton's hypothesis that a simple movement rule could reduce predation risk and encourage grouping behavior. Simulations showed little effect of this nearest-neighbor rule on predation risk. Similar, more complicated rules reduced predation risk by up to two thirds. The second focus was on the accuracy of ground observers in diagramming individual animal locations in small herds of elk. A remotely controlled airplane was used to photograph the herds from above. A substantial distance discrepancy was found between "true" and "observed" animal locations. This discrepancy increased with group size and was different between observers but not between herds. Observers were better at predicting relative animal locations than absolute animal locations. The third consideration was interanimal spacing in bison herds photographed from an airplane during a three-month period. At later dates photographed herds were located, and cover-sampling methods were adapted to estimate bison visibility in each area. These data were used in linear regression models which explained over two-thirds of the variance in nearest-neighbor distance. Important indicator variables were the number of animals in the herd, a cover measurement, the north and east location of herds, the time photographed, and the fraction of the animals standing. The fourth focus was the development of simulations of simple movement rules used to mimic grouping behavior. Individuals moved according to two simple first nearest-neighbor rules: if within a minimum distance, move directly away, and if outside a maximum distance, move directly toward. Four other rules were used to determine individual states. Two different measurements were made for each simulation run: the overall mean nearest-neighbor distance and the overall mean subgroup size. Results showed that the means and variances of near-neighbor distances decreased as the number of individuals in the simulation increased. Different near-neighbor rules had little effect on mean nearest neighbor distance. All rules produced results similar to each other and different from bison data. A random model was more similar to the bison data.
5

Managing human footprint with respect to its effects on large mammals: implications of spatial scale, divergent responses and ecological thresholds

Toews, Mary 03 October 2016 (has links)
The environmental problems facing the world today are largely attributable to anthropogenic activities and landscape change. Addressing these challenges in an evidence-based way requires an understanding of precisely how species and ecosystems are responding to human impacts. Discerning linkages between stressors and their ecological repercussions, and using this to inform conservation, can be challenging due to the complexity and uncertainty of ecological research. I focused on the responses of five wide-ranging large mammal species – gray wolf (Canis lupus), Canada lynx (Lynx canadensis), coyote (Canis latrans), white-tailed deer (Odocoileus virginianus) and moose (Alces alces) – to human footprint (measure of human infrastructure and landscape change), using 12 years (2001-2013) of snowtrack surveys conducted across the boreal forest of Alberta. I explored three key challenges to discerning the linkages between ecological dynamics and management actions. First, I asked whether the direction and magnitude of species responses vary depending on the spatial extent and grain of the study. Second, I asked whether these species respond more strongly to individual footprint features or to the cumulative effects of footprint (measured as total footprint), and whether responses to footprint are consistent across species. Third, I evaluated the utility of thresholds for large mammal management and asked whether there is evidence for consistent threshold responses to total footprint across scales. In addressing the first two questions, I evaluated a set of generalized linear mixed effects models (GLMM) relating the relative abundance of each species to individual and cumulative effects of human footprint, using an information-theoretic approach. I compared the direction of species responses across our regional study area (approximately 400,000 km2) to those reported in previous smaller-extent studies (median 1,525 km2), and compared responses across three spatial grains (250m, 1500m, and 5000m transect buffers). In addressing the third question, I conducted a review on the utility of ecological thresholds, described as abrupt changes in the response to a continuous driver, for large mammal management. I further tested for thresholds in species responses to total footprint by comparing linear models (logistic regression) to piecewise regression models. I compared threshold values between two grains (approximately 33km2 - 1500m transect buffer, and 5500km2 - grouping transects into clusters), and across four regions (boreal forest extent, three landscape planning units). I found that the direction of species responses varied with spatial extent, but not grain, and that species responded strongly to a broad suite of footprint features, indicating the need to manage for cumulative effects. Despite the appeal of ecological thresholds, using these as targets is challenging and the success of doing so has rarely been evaluated. I found threshold models to be better supported than linear ones across species, but due to variability and uncertainty in threshold values, the results are more suited as guidelines or hypotheses to be further tested, as opposed to specific management targets. Translating research on complex ecological systems into management actions is a continuing challenge, yet, ongoing biodiversity monitoring and adaptive management may refine our existing tools, and ultimately lead to better environmental stewardship. / Graduate / 2017-09-05 / 0329
6

Effects of anthropogenic pressure on large mammal species in the Hyrcanian forest, Iran / Effects of poaching, logging and livestock grazing on large mammals

Soofi, Mahmood 08 December 2017 (has links)
No description available.
7

O conhecimento de agricultores quilombolas sobre forrageio e uso de habitat por mamíferos de grande porte na Mata Atlântica: evidenciando a centralidade dos ambientes antropogênicos na constituição do etnoconhecimento (Vale do Ribeira, SP, Brasil) / The perception of quilombola smallholders concerning the foragin and habitat use of large mammals in the Atlantic Forest: evincing the centrality of anthropogenic environments in local knowledge (Ribeira Valley, Brazil)

Prado, Helbert Medeiros 18 June 2012 (has links)
A etnoecologia investiga as relações entre os humanos e o seu ambiente natural, incluindo o estudo do conhecimento ecológico de populações locais (CEL) sobre interações entre as espécies e destas com o ambiente. Suas principais temáticas de interesse incluem a compreensão do CEL em termos de: sua construção e compartilhamento entre as pessoas, suas mudanças frente a processos de modernização vivenciados por populações rurais, bem como suas similaridades e divergências em relação ao conhecimento científico normativo. Esta tese é um estudo em etnoecologia que se concentra principalmente (1) nas comparações entre o CEL e o conhecimento científico normativo, e (2) na relevância de diferentes elementos da paisagem na formação do repertório presente no CEL. Nesta pesquisa, o CEL é analisado em termos do conjunto de conhecimentos locais sobre aspectos ecológicos de mamíferos de médio e grande porte na Mata Atlântica. O estudo foi realizado no contexto de três comunidades remanescentes de quilombo do Vale do Ribeira (SP, Brasil). Estas comunidades se originaram a partir de contingentes de escravos fugidos ou abandonados na região há pelo menos dois séculos, e adotaram como principal atividade de subsistência na Mata Atlântica a agricultura de coivara - prática comum nos trópicos e caracterizada principalmente por seu sistema de descanso (pousio) e rotatividade do solo. A prática histórica da coivara por sua vez definiu em grande parte a composição e a configuração da paisagem que se observa atualmente na região. O CEL foi registrado a partir da aplicação de entrevistas, semi estruturadas, estruturadas e de listagens livres, abordando questões sobre dieta e uso de habitat pelas espécies. O conhecimento científico sobre a dieta da fauna, utilizado como parâmetro para comparação com o CEL, foi reunido por meio de uma revisão da literatura ecológica sobre o tema. Já os dados envolvendo uso de habitat pelas espécies foram obtidos através do registro in situ das mesmas na paisagem, pela técnica de armadilhamento fotográfico realizado no presente estudo. Resultados de interesse ecológico e etnoecológico foram obtidos. Na revisão crítica dos estudos sobre dieta de ungulados neotropicais, importantes limitações metodológicas foram identificadas, e podem servir de base de reflexão para pesquisas futuras nesse campo. Já com relação ao uso de habitat pela fauna, a partir do registro faunístico in situ, observou-se que o contexto das matas secundárias (antigas roças de coivara) se mostrou tão atrativo para a maioria das espécies analisadas quanto o ambiente de mata madura. Esses resultados, juntamente com as informações de estudos prévios ressaltando a importância tanto material quanto cultural da agricultura de coivara, bem como seus impactos reduzidos na paisagem, ressaltam o caráter desproporcional com que esta prática vem sendo desencorajada pelos órgãos ambientais do Estado. No campo da etnoecologia, esta tese mostra que os níveis de consenso populacional e de convergência em relação ao conhecimento científico variaram de acordo com os diferentes aspectos ecológicos considerados sobre as espécies em questão, como dieta, uso de habitat e hábito de vida (diurno/noturno). Já as comparações com o conhecimento científico, com o foco em diferentes elementos da paisagem, evidenciaram uma maior saliência do contexto ambiental das matas secundárias (antigas roças), e dos espaços da roça e dos quintais antigos na formação do repertório desse conhecimento. Em contrapartida, nas últimas três décadas, as populações aqui estudadas têm experimentado uma série de transformações, caracterizadas principalmente pela formação de vilas semi-urbanizadas e o abandono quase completo do sistema de coivara como prática agrícola local. Considerando que nesse processo as gerações mais novas não mais vivenciam suas práticas na paisagem, como os mais velhos o faziam, é razoável considerar a hipótese de que o CEL destes jovens venha a se constituir num repertório cada vez mais reduzido em relação àquele que ainda persiste entre os indivíduos mais velhos da população. / Ethnoecology deals with the relations between humans and the natural environment, which includes the study of the local ecological knowledge (LEK) concerning interactions among species between species and the environment. The study\'s main thematic interests center upon understanding how LEK is built and shared, how it changes in the face of processes of modernization experienced by rural populations, and how it corroborates and/or contradicts normative scientific knowledge. This thesis is an ethnoecological study that focuses primarily on (1) comparisons between LEK and normative scientific knowledge, and (2) the relevance of different landscape elements in the formation of LEK repertoires. In this study, LEK is analyzed in terms of the existing body of local knowledge concerning ecological aspects of the large mammals in the Atlantic Forest. The study was carried out in three quilombolas communities in the Ribeira Valley (São Paulo, Brazil). These communities originated from maroon colonies formed by runaway and abandoned slaves some two centuries ago. These settlers lived off the Atlantic Forest, adopting the shifting cultivation system known as coivara, a common form of subsistence agriculture in the Tropics. This practice of coivara largely determined the composition and configuration of the local landscape such as it is today. Local Ecological Knowledge was gathered through semi-structured and structured interviews and free-listing, covering such issues as species diet and habitat use. The scientific knowledge on these same diets, which was used as a parameter of comparison with the LEK, was gleaned through a review of the ecological literature on the theme. Data on habitat use was gathered in situ using camera trapping technique. Results of ecological and ethnoecological interest were obtained. Significant methodological limitations were identified during the critical review of studies on Neotropical ungulate diets, providing a basis for reflection in future studies. Regarding habit use by fauna, in situ observation showed that secondary forest (old swidden plots) proved just as attractive to most of the species as did mature forest. These results, combined with the findings of previous researches emphasizing the material and cultural importance of coivara and its relatively low impact on the landscape, underline the disproportionate vigor with which the practice has been discouraged by environmental organs. In the field of ethnoecology, this thesis shows that the levels of local consensus and LEK convergence with the scientific knowledge varied depending on the ecological aspects considered for the species in question, such as diet, habitat use and foraging habits (diurnal/nocturnal). Comparison with the scientific knowledge, with focus on the different landscape elements, revealed greater relevance of the environmental context of secondary forest (regrowth), cultivated plots and homegardens in the formation of this local knowledge repertoire. Over the course of the last three decades, the study populations have experienced a series of transformations brought about by agglomeration in semi-urbanized villages and the near-total abandonment of the coivara system as the mainstay of local agricultural practice. Seen as the younger generations have had far less exposure to the traditional practice than their elders, it is reasonable to assume that the LEK they possess will yield an increasingly limited repertoire in comparison with that currently preserved by the older generations.
8

O conhecimento de agricultores quilombolas sobre forrageio e uso de habitat por mamíferos de grande porte na Mata Atlântica: evidenciando a centralidade dos ambientes antropogênicos na constituição do etnoconhecimento (Vale do Ribeira, SP, Brasil) / The perception of quilombola smallholders concerning the foragin and habitat use of large mammals in the Atlantic Forest: evincing the centrality of anthropogenic environments in local knowledge (Ribeira Valley, Brazil)

Helbert Medeiros Prado 18 June 2012 (has links)
A etnoecologia investiga as relações entre os humanos e o seu ambiente natural, incluindo o estudo do conhecimento ecológico de populações locais (CEL) sobre interações entre as espécies e destas com o ambiente. Suas principais temáticas de interesse incluem a compreensão do CEL em termos de: sua construção e compartilhamento entre as pessoas, suas mudanças frente a processos de modernização vivenciados por populações rurais, bem como suas similaridades e divergências em relação ao conhecimento científico normativo. Esta tese é um estudo em etnoecologia que se concentra principalmente (1) nas comparações entre o CEL e o conhecimento científico normativo, e (2) na relevância de diferentes elementos da paisagem na formação do repertório presente no CEL. Nesta pesquisa, o CEL é analisado em termos do conjunto de conhecimentos locais sobre aspectos ecológicos de mamíferos de médio e grande porte na Mata Atlântica. O estudo foi realizado no contexto de três comunidades remanescentes de quilombo do Vale do Ribeira (SP, Brasil). Estas comunidades se originaram a partir de contingentes de escravos fugidos ou abandonados na região há pelo menos dois séculos, e adotaram como principal atividade de subsistência na Mata Atlântica a agricultura de coivara - prática comum nos trópicos e caracterizada principalmente por seu sistema de descanso (pousio) e rotatividade do solo. A prática histórica da coivara por sua vez definiu em grande parte a composição e a configuração da paisagem que se observa atualmente na região. O CEL foi registrado a partir da aplicação de entrevistas, semi estruturadas, estruturadas e de listagens livres, abordando questões sobre dieta e uso de habitat pelas espécies. O conhecimento científico sobre a dieta da fauna, utilizado como parâmetro para comparação com o CEL, foi reunido por meio de uma revisão da literatura ecológica sobre o tema. Já os dados envolvendo uso de habitat pelas espécies foram obtidos através do registro in situ das mesmas na paisagem, pela técnica de armadilhamento fotográfico realizado no presente estudo. Resultados de interesse ecológico e etnoecológico foram obtidos. Na revisão crítica dos estudos sobre dieta de ungulados neotropicais, importantes limitações metodológicas foram identificadas, e podem servir de base de reflexão para pesquisas futuras nesse campo. Já com relação ao uso de habitat pela fauna, a partir do registro faunístico in situ, observou-se que o contexto das matas secundárias (antigas roças de coivara) se mostrou tão atrativo para a maioria das espécies analisadas quanto o ambiente de mata madura. Esses resultados, juntamente com as informações de estudos prévios ressaltando a importância tanto material quanto cultural da agricultura de coivara, bem como seus impactos reduzidos na paisagem, ressaltam o caráter desproporcional com que esta prática vem sendo desencorajada pelos órgãos ambientais do Estado. No campo da etnoecologia, esta tese mostra que os níveis de consenso populacional e de convergência em relação ao conhecimento científico variaram de acordo com os diferentes aspectos ecológicos considerados sobre as espécies em questão, como dieta, uso de habitat e hábito de vida (diurno/noturno). Já as comparações com o conhecimento científico, com o foco em diferentes elementos da paisagem, evidenciaram uma maior saliência do contexto ambiental das matas secundárias (antigas roças), e dos espaços da roça e dos quintais antigos na formação do repertório desse conhecimento. Em contrapartida, nas últimas três décadas, as populações aqui estudadas têm experimentado uma série de transformações, caracterizadas principalmente pela formação de vilas semi-urbanizadas e o abandono quase completo do sistema de coivara como prática agrícola local. Considerando que nesse processo as gerações mais novas não mais vivenciam suas práticas na paisagem, como os mais velhos o faziam, é razoável considerar a hipótese de que o CEL destes jovens venha a se constituir num repertório cada vez mais reduzido em relação àquele que ainda persiste entre os indivíduos mais velhos da população. / Ethnoecology deals with the relations between humans and the natural environment, which includes the study of the local ecological knowledge (LEK) concerning interactions among species between species and the environment. The study\'s main thematic interests center upon understanding how LEK is built and shared, how it changes in the face of processes of modernization experienced by rural populations, and how it corroborates and/or contradicts normative scientific knowledge. This thesis is an ethnoecological study that focuses primarily on (1) comparisons between LEK and normative scientific knowledge, and (2) the relevance of different landscape elements in the formation of LEK repertoires. In this study, LEK is analyzed in terms of the existing body of local knowledge concerning ecological aspects of the large mammals in the Atlantic Forest. The study was carried out in three quilombolas communities in the Ribeira Valley (São Paulo, Brazil). These communities originated from maroon colonies formed by runaway and abandoned slaves some two centuries ago. These settlers lived off the Atlantic Forest, adopting the shifting cultivation system known as coivara, a common form of subsistence agriculture in the Tropics. This practice of coivara largely determined the composition and configuration of the local landscape such as it is today. Local Ecological Knowledge was gathered through semi-structured and structured interviews and free-listing, covering such issues as species diet and habitat use. The scientific knowledge on these same diets, which was used as a parameter of comparison with the LEK, was gleaned through a review of the ecological literature on the theme. Data on habitat use was gathered in situ using camera trapping technique. Results of ecological and ethnoecological interest were obtained. Significant methodological limitations were identified during the critical review of studies on Neotropical ungulate diets, providing a basis for reflection in future studies. Regarding habit use by fauna, in situ observation showed that secondary forest (old swidden plots) proved just as attractive to most of the species as did mature forest. These results, combined with the findings of previous researches emphasizing the material and cultural importance of coivara and its relatively low impact on the landscape, underline the disproportionate vigor with which the practice has been discouraged by environmental organs. In the field of ethnoecology, this thesis shows that the levels of local consensus and LEK convergence with the scientific knowledge varied depending on the ecological aspects considered for the species in question, such as diet, habitat use and foraging habits (diurnal/nocturnal). Comparison with the scientific knowledge, with focus on the different landscape elements, revealed greater relevance of the environmental context of secondary forest (regrowth), cultivated plots and homegardens in the formation of this local knowledge repertoire. Over the course of the last three decades, the study populations have experienced a series of transformations brought about by agglomeration in semi-urbanized villages and the near-total abandonment of the coivara system as the mainstay of local agricultural practice. Seen as the younger generations have had far less exposure to the traditional practice than their elders, it is reasonable to assume that the LEK they possess will yield an increasingly limited repertoire in comparison with that currently preserved by the older generations.
9

Padrões de distribuição de mamíferos de médio e grande porte em paisagens fragmentadas / Distribuition patterns of medium and large size mammals in fragmented landscapes

BERNARDO, Paulo Vitor dos Santos 03 April 2012 (has links)
Made available in DSpace on 2014-07-29T16:21:19Z (GMT). No. of bitstreams: 1 Dissertacao_Paulo_Bernardo.pdf: 1129022 bytes, checksum: 7c040610be6ff90732215785459de5f2 (MD5) Previous issue date: 2012-04-03 / Habitat fragmentation is defined as the breaking of a continuous habitat in patches or fragments. This process leads to environmental changes capable of affecting communities in different ways, causing species composition changes. Beta diversity measures can show the variation between the composition of different communities, where two ecological patterns can be found: turnover and nestedness. In turnover the variation in community structure is a consequence of species replacement, while in the nestedness poor communities are nested in richer communities. Here I tested: (I) how habitat fragmentation affects the presence of large e medium sized mammals in different functional groups; (II) if the variation in beta diversity in fragmented landscapes is caused by turnover or nestedness, and (III) if the variation observed was due to habitat fragmentation. I used 19 Semidecidous Forest patches in the Brazilian Cerrado, from the State of Goiás. Landscape metrics from 2.5 km around the patches were obtained from classifications and measurements. For the analyses, I made four sets based in diet, size, diet amplitude and all previous three together. I calculated the beta diversity with Sorensen indices, turnover with Simpson indices and nestedness with Nestedness indices. The natural area size influenced the group B3- felines and the core area percentage, the groups A1-carnivores, larges and B3-felines. The core area percentages were the most important character in fragmented landscapes for mammal communities. The felines were the most sensible group. This group was affected by natural area availability and by the core area percentage. The beta diversity pattern in the fragmented landscapes was turnover, but it was not related to environmental variation or spatial distances between the landscapes. Both nestedness and beta diversity were affected by spatial distance, but beta diversity was also affected by environmental variation linked to landscape connectivity. The changes in different landscapes cause different responses in species and allow the creation of a fragmentation gradient, driving the turnover phenomenon. The carnivores were the species most sensible to habitat fragmentation, mainly because they need large home ranges. Thus, an understanding of how diversity reacts to habitat fragmentation may provide support to the implementation of conservation areas and research upgrading which focus specific species groups. Managed areas with large core areas and good connectivity should bring desirable results for large and medium sized mammals conservation status. This affirmative is true, especially for larger mammals and carnivores. / A fragmentação de habitats pode ser entendida como a quebra de um habitat contínuo em pedaços ou fragmentos. As alterações ambientais provenientes desse processo influenciam as comunidades de diferentes formas podendo causar variações em sua composição de espécies. A diversidade beta pode ser um indicativo da variação entre a composição das comunidades, podendo gerar dois padrões de variação, o turnover e o aninhamento. No turnover ocorre a substituição de espécies ao longo das comunidades, enquanto no aninhamento há a formação de subgrupos a partir de comunidades mais ricas. Neste trabalho testei: (I) como a fragmentação de habitats influencia a presença dos mamíferos de médio e grande porte agrupados em grupos funcionais; (II) como a diversidade beta está sendo influenciada por estes processos de fragmentação de habitats, levando a um padrão de substituição ou aninhamento de espécies e se as mudanças podem ser atribuídas à fragmentação. Utilizei dados de amostragens de mamíferos de médio e grande porte em 19 fragmentos de Floresta Estacional Semidecidual localizados no bioma Cerrado no estado de Goiás. A paisagem que se encontrava 2,5 Km ao redor dos fragmentos foi mapeada, e neste perímetro calculada as métricas da paisagem. Para análise, formei quatro conjuntos de grupos com os mamíferos, baseados na dieta, na massa corporal, na amplitude de nicho trófico e na junção dos três anteriores. A diversidade beta foi calculada segundo o índice de Sorensen, o turnover pelo índice de Simpson e o aninhamento pelo índice de Nestedness. A quantidade de área influenciou a presença do grupo B3 felinos e a porcentagem de área nuclear os grupos A1 carnívoros, grandes e B3- felinos. A porcentagem de área nuclear na paisagem é a característica mais importante para a presença dos mamíferos na paisagem fragmentada. Os felinos foram o grupo mais sensível sendo influenciados pela quantidade de área e porcentagem de área nuclear. A diversidade beta nas paisagens fragmentadas está estruturada pela substituição de espécies, mas somente a diversidade beta foi influenciada pela variação ambiental relacionada a conectividade das paisagens. As diferentes alterações nas paisagens provocam diferentes respostas nas espécies e permitem a criação de um gradiente de fragmentação impulsionando o processo de substituição de espécies. A manutenção de fragmentos com grande quantidade de área nuclear e boa conectividade favorece a conservação de mamíferos, principalmente os de grande porte e carnívoros.
10

Monitoramento e avaliação das passagens inferiores de fauna presentes na rodovia SP-225 no município de Brotas, São Paulo / Monitoring and evaluation of the fauna underpasses located on SP-2525 highway in the city of Brotas, São Paulo

Abra, Fernanda Delborgo 17 September 2012 (has links)
A Ecologia de Estradas é um novo campo de conhecimento e surgiu das demandas sobre estudos de impactos ambientais em áreas naturais, com a construção de empreendimentos lineares, como estradas, rodovias e linhas férreas. Sérios problemas ambientais ligados à implantação de estradas e rodovias estão sendo analisados em todo o mundo, como: dispersão de espécies exóticas, alteração do ciclo hidrológico, mudanças microclimáticas, produção de material particulado e ruído, contaminação das águas e do solo, perda de habitat, fragmentação de ambientes naturais e, principalmente, o atropelamento de animais silvestres. Vários estudos vêm sendo desenvolvidos especialmente na América do Norte e Europa e medidas mitigatórias para o atropelamento de animais silvestres, como as passagens de fauna, vêm sendo criadas. Essas estruturas restituem a conectividade entre os fragmentos florestais e matrizes permeáveis e, quando efetivas nas travessias de animais, contempla-se a conservação da biodiversidade e a segurança do usuário. O estado de São Paulo possui 81 passagens de fauna em 14 rodovias diferentes e, numa delas, a SP-225, foi realizado o monitoramento de 10 passagens inferiores de fauna (PIF), distribuídas em 51 km de extensão. O trecho da rodovia em estudo corta os municípios de Dois Córregos, Brotas e Itirapina. Os objetivos deste trabalho foram comparar a efetividade em travessias de mamíferos de médio e grande porte entre diferentes tipos estruturais de PIF, novas e antigas (presentes antes do licenciamento da duplicação da rodovia), com presença e ausência de água. Três tipos diferentes de PIF foram monitorados: passagens quadradas de concreto, redondas de tubo Armco e um terceiro tipo de grande galeria. Também verificamos a influência da paisagem num entorno de 50 metros (buffers) ao redor das PIFs estudadas. O monitoramento foi realizado por meio de filmagens com câmeras digitais de vídeo e canteiros de pegadas com pó de mármore, durante oito dias por mês, no período de um ano, totalizando um esforço amostral de 96 dias. Foram registradas 800 travessias, sendo que 725 foram exclusivas para mamíferos de médio e grande porte, tendo 16 diferentes espécies representadas. As espécies que mais utilizaram as passagens foram capivara (Hydrochoerus hydrochaeris), com 435 travessias de indivíduos, seguido de veado catingueiro (Mazama gouazoubira), com 94 indivíduos, e tatu galinha (Dasypus novemcinctus), com 52 indivíduos. Os resultados foram testados através de análises de variância e teste correlação de Spearman. Verificou-se que a presença de água é um fator altamente significativo para a travessia da fauna (X2 = 236,5; p<<0,001). Não detectamos diferença na efetividade dos três tipos de PIF estudados (ANOVA: F= 1.43, p= 0,255) embora o tipo \"grande galeria\" tenha contemplado a travessia de 15 espécies diferentes, apresentando, portanto, maior riqueza. O baixo número amostral para PIF do tipo grande galeria impediu o uso de seus resultados em testes estatísticos, porém, uma maior amostragem talvez pudesse mostrar maior sucesso desse tipo de PIF. É possível que passagens redondas e quadradas não tenham diferido no número de travessias por terem em média o mesmo tamanho (2 m x 2 m em PIFs quadradas e 2 m de diâmetro em PIFs redondas), pois talvez os mamíferos de médio e grande porte não tenham predileção por tipos estruturais específicos entre essas duas PIFs. A análise da paisagem no entorno da rodovia demonstrou que as matrizes mais presentes foram as culturas de laranja e pasto, mas a única espécie que respondeu aos tipos de matrizes foi o gambá (Didelphis albiventris), estando freqüente em passagens circundadas por cana de açúcar e pasto. Analisando a ocorrência das espécies estudadas nas PIFs, verificamos que cachorro do mato (Cerdocyon thous) e tatu (Dasypus novemcinctus) se mostraram relacionados negativamente com a presença de água (p= -0,72 e p= -0,62 respectivamente, teste de Spearman), enquanto que veado, gambá e paca se mostraram relacionados positivamente com a presença de vegetação. É possível relacionar o sucesso de travessias de mamíferos de médio e grande porte com PIFs apresentando água também dentro dos limites da paisagem considerados. Nesse sentido, tivemos 676 travessias em passagens úmidas e 46 travessias em passagens secas. A aplicação prática dessa informação é a possibilidade de modificação de tubos de drenagem fluviais já existentes em rodovias (com dimensão mínima de 1,5 m de diâmetro, ou 1,5 m x 1,5 m para caixas retangulares) para a passagem de fauna, ou a construção de novos tubos adaptados para fauna de médio e grande porte nas rodovias em licenciamento para implantação ou duplicação / Road Ecology is a new field of knowledge that emerged from environmental impact studies in natural areas due to the construction of linear developments, such as roads, highways and railways. Serious environmental problems linked to the construction of roads and highways have been analyzed worldwide, such as: dispersion of exotic species, hydrological cycle changes, microclimatic changes, the production of particulate material and noise, water and soil contamination, habitat loss, natural environments fragmentation, and road kill. Many studies have been conducted especially in North America and Europe resulting in mitigation measures such as fauna crossings for the reduction of road kill. These structures restore the connectivity between forests fragments and permeable matrices, the conservation of biodiversity and safety of users is taken into consideration when it is effective for the crossings of animals. Sao Paulo State has 81 fauna crossings in 14 different highways and, in particular, there was monitoring of 10 fauna underpasses, on the SP-225 distributed over 51 km. The section of the highway in the study cuts through the municipalities of Dois Corregos, Brotas and Itirapina. The purpose of this study was to compare the different structural types, new and old (present prior to the highway duplication licensing), with and without the presence of water and their effectiveness on medium and large-sized mammals usage of fauna underpasses. Three different types of fauna underpasses were monitored: square concrete underpass, Armco tube tunnels and a third type of open spam underpass. We also verified the influence of the landscape within 50 meters (buffers) surrounding the fauna underpasses studied. The monitoring was made utilizing digital video recording cameras and marble dust beds track stations, eight days a month, during one year, the sampling totaling 96 days. There were 800 crossings registered, 725 were exclusively for medium and largesized mammals, representing 16 different species. The species that most used the crossings were the capybara (Hydrochoerus hydrochaeris), 435 crossings of the individuals, followed by the gray brocket deer (Mazama gouazoubira), with 94 individuals, and the nine-banded armadillo (Dasypus novemcinctus ), with 52 individuals. The results were tested through the analysis of variance and Spearman correlation test. It was found that the presence of water is a highly significant factor for the fauna crossing (X2 = 236,5; p<<0,001). We detected no difference in the effectiveness of the three types of underpasses studied (ANOVA: F= 1.43, p= 0,255) although the type \"open spam underpass\" demonstrated greater diversity with the crossings of 15 different species. The low sampling number for the type of open spam underpass prevented the usage of the results in statistical tests; however a larger sampling would probably be able to show a greater success of this type of fauna underpass structure. It is possible that there had not been a difference in the number of crossings in round culverts and square culverts because these structures have on average the same size (2m x 2m in square underpasses and 2m in diameter in round underpasses). Maybe because medium and large-sized mammals don\'t have a preference for specific structural types between these two types of fauna underpasses. The analysis of the landscape in the surrounding areas of the highway showed that the cultures of orange and pasture were the prevalent matrices, but the white-eared opossum (Didelphis albiventris) was the only specie that responded to these types of matrices. The white-eared opossum was found frequently in landscapes surrounded by sugar cane and pasture. Analyzing the occurrence of the species studied in the fauna underpasses, we verified that crab eating fox and armadillo demonstrated a negative interaction with water (p= -0,72 e p= -0,62 respectively, Spearman test), whereas gray brocket, white eared opossum and spotted paca demonstrated a positive interaction with the presence of vegetation

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