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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.
11

Mamíferos terrestres de maior porte e a invasão de cães domésticos em remanescentes de uma paisagem fragmentada de Mata Atlântica: avaliação da eficiência de métodos de amostragem e da importância de múltiplos fatores sobre a distribuição das espécies / Terrestrial large mammals and invasion of domestic dogs in remnants of an Atlantic Forest fragmented landscape: evaluation of the efficiency of sampling methods and of the importance of multiple factors on species distribution.

Espartosa, Karina Dias 12 March 2009 (has links)
Nessa dissertação, avaliei a eficiência e congruência de métodos para amostragem de mamíferos de maior porte e investiguei a influência de fatores múltiplos correlacionados, comuns em paisagens fragmentadas, sobre a distribuição destes animais em remanescentes de Mata Atlântica. Através de amostragens padronizadas em 24 remanescentes florestais de uma paisagem rural com 49% de remanescentes florestais no Planalto Paulista e de um delineamento pareado, no capítulo 2 comparei o desempenho e a congruência de dois métodos (pegadas em parcelas de areia e armadilhas fotográficas) e de dois tipos de isca (banana e iscas de cheiro) para a estimativa da riqueza e taxa de ocorrência de mamíferos de maior porte. Ambos os métodos se mostraram adequados para o estudo destes animais em florestas tropicais e dos fatores que afetam sua distribuição em paisagens alteradas, pois (1) registram as espécies de menor porte e noturnas, (2) podem ser padronizados entre áreas heterogêneas, (3) apresentam desempenho semelhante no registro da maioria das espécies e da riqueza de espécies, e (4) refletem de maneira similar o padrão de ocorrência das espécies entre diferentes áreas. Frente às iscas de cheiro utilizadas, a banana foi a isca mais eficiente na amostragem tanto das espécies herbívoras/frugívoras quanto das espécies onívoras, destacando a necessidade da padronização das iscas utilizadas e do uso de iscas complementares ou de iscas que atraiam uma ampla gama de animais. Usando os dados obtidos com armadilhas fotográficas, avaliei quais fatores condicionam a presença e a freqüência de ocorrência de cães domésticos (capítulo 3) e de mamíferos de maior porte (capítulo 4) nos remanescentes. Esta avaliação foi realizada através da seleção de modelos de regressão construídos com base na relação causal entre os fatores estudados - que pode ser estabelecida a partir de como usualmente se dá a expansão das atividades humanas em florestas neotropicais - e comparados através do critério de informação AIC (The Akaike Information Criterion). Para o cão doméstico, foram considerados quatro fatores: extensão de estradas, quantidade de mata e número de cães domésticos no entorno, e qualidade da vegetação. Foi observada uma forte relação positiva entre o total de residentes e o total de cães domésticos no entorno dos remanescentes. Dentro dos remanescentes, o cão doméstico foi mais registrado do que sete das 11 espécies nativas, sua ocorrência foi mais bem explicada pela quantidade de cães no entorno, e sua freqüência de ocorrência pela diminuição da quantidade de mata no entorno, o que mostra a necessidade de controle populacional desta espécie no entorno de áreas naturais e da manutenção de áreas florestadas mais extensas, menos suscetíveis a entrada deste invasor. Para os mamíferos de maior porte, os fatores considerados foram: quantidade de mata e número de residentes no entorno dos remanescentes, distância à estrada de asfalto, freqüência de ocorrência de cães domésticos nos remanescentes, e qualidade da vegetação dos remanescentes. Os resultados demonstraram que, apesar da ampla variação na resposta das espécies a estes fatores, a distância a estradas de asfalto e a freqüência de ocorrência de cães domésticos, fatores que são correlacionados a disponibilidade de habitat e não são freqüentemente considerados, determinaram a distribuição de um número maior de espécies. A comunidade de mamíferos de maior porte encontrada é simplificada, dominada por espécies generalistas e com poucos dispersores e predadores de sementes e plântulas, o que pode levar a conseqüências negativas para outras espécies e para o funcionamento e regeneração das florestas remanescentes. Estes resultados sugerem que para a conservação de uma comunidade íntegra de mamíferos de maior porte na Mata Atlântica é necessário, não apenas a manutenção de grandes contínuos de mata nativa ou de paisagens com percentual alto de matas remanescentes, mas a redução drástica das perturbações associadas à ocupação e atividades humanas. O manejo e restauração de paisagens devem considerar a proximidade entre os remanescentes florestais e estradas, principalmente as asfaltadas e de alto tráfego, e a importância de campanhas de controle populacional e vacinação de cães domésticos. / In this master thesis, I evaluated the efficiency and congruence of methods for sampling large mammals, and investigated the influence of multiple and correlated factors, common in fragmented landscapes, on the distribution of these animals in Atlantic Forest remnants. Through standardized surveys at 24 forest remnants in a rural landscape with 49% of remaining forest in the Planalto Paulista and using a paired design, in chapter 2 I compared the performance and the congruence of two methods (tracks in sand plots and camera-trapping) and of two types of baits (banana and scent lures) for estimating richness and rate of occurrence of large mammals. Both methods are suitable for studying these animals in tropical forests as well as the factors that affect their distribution in disturbed landscapes, because (1) they record medium-sized and nocturnal species, (2) can be standardized among heterogeneous sites, (3) present similar performance for recording most species and richness, (4) reflect in similar ways the pattern of species occurrence among different sites. Compared with scent lures, banana was the most efficient bait for sampling herbivores/frugivores as well as omnivores, highlighting the need to standardize baits and use complementary baits or baits that attract a wide range of animals. Using camera-trapping data, I evaluated which factors determine the presence and the frequency of occurrence of domestic dogs (chapter 3) and of large mammals (chapter 4) in remnants. This evaluation was done through the selection of regression models buit based on the causal relationship among studied factors which can be established from the way expansion of human activities usually happens in neotropical forests and compared through the AIC, The Akaike Information Criterion. For the domestic dog, four factors were considerate: extension of roads, amount of forest and number of domestic dogs in the surroundings, and vegetation quality. It was observed a strong positive relationship between the total number of residents and the total number of domestic dogs in the surroundings. Inside remnants, the domestic dog was more frequently recorded than seven of the 11 native species, its occurrence was better explained by the number of dogs in the surroundings, and its frequency of occurrence by the reduction of the amount of forest in the surroundings, which indicates the need of population control of this invasive species in the surroundings of natural areas and of the maintenance of extensive forests areas that are less susceptible to the entrance of this invasive species. For native large mammals, the considered factors were: amount of forest and number of residents in the surroundings, distance from paved roads, frequency of occurrence of domestic dogs and vegetation quality. Results suggested that, despite the large variation in the responses of species to the studied factors, distance from paved roads and frequency of occurrence of domestic dog, factors that are correlated with habitat availability and are not frequently considered, determined the distribution of a larger number of species. The large mammal community found is simplified, dominated by generalist species and with few seed and seedling dispersers and predators, which can lead to negative consequences to other species and to forest functioning and regeneration. These results suggest that for conserving a complete large mammal community at the Atlantic Forest, not only the maintenance of large tracts of continuous forest or landscapes with high percentage of remaining forest is needed, but also a drastic reduction of disturbances associated with human activities and occupation. Landscape management and restoration should consider the proximity between forest remnants and roads, especially those that are paved and present high traffic, and the importance of campaigns of domestic dog population control and vaccination.
12

Variabilité des comportements alimentaires au Paléolithique moyen en France septentrionale : apports des études archéozoologiques / Variability of food behavior in the Middle Palaeolithic from Northern France : a zooarchaeological study

Seveque, Noemie 20 December 2017 (has links)
L'Europe du Nord-Ouest, plus particulièrement la France septentrionale, constitue durant le Pléistocène moyen et supérieur un carrefour biogéographique. Les populations animales, et donc les Hommes, y évoluent en fonction des variations climatiques et environnementales. La grande richesse des vestiges fauniques a permis de réaliser une étude archéozoologique et paléoécologique sur l'ensemble des niveaux de trois gisements datés du Pléistocène supérieur : Caours (Somme) pour l'Eemien, Le Rozel (Manche) et Mutzig (Bas-Rhin) pour le début Weichsélien. Une reprise partielle du matériel dentaire de Biache-Saint-Vaast (Pas-de-Calais) daté de la fin de Saalien a également été faite. L'étude des séries fauniques, majoritairement basée sur la réalisation de profils de mortalité et la détermination de la saisonnalité d'occupation des niveaux archéologiques, a permis de mettre en évidence des comportements de subsistance récurrents dans les différents gisements : chasse principalement ciblée sur les cervidés, transport sélectif des cadavres en fonction de la taille des animaux et exploitation intensive à but alimentaire avec la récupération de la viande, de la moelle et de la langue. Malgré une grande homogénéité dans la gestion du gibier et du territoire, certains comportements tendent à être plus variables : exploitation des cadavres à but utilitaire avec la récupération des peaux, des fourrures et l'utilisation des os en tant que retouchoir, et sélection d'individus en particulier en fonction de l'âge et/ou du sexe. Les Néandertaliens de France septentrionale montrent ainsi une grande homogénéité dans leurs comportements de subsistance, mais également une variabilité qui découle de leur adaptation constante à leur milieu. / Northwestern Europe is during the Middle and Late Pleistocene a biogeographical crossword, in particular Northern France. Large mammals and Humans are present depending on the climatic and environmental variations. The huge amount of preserved bones coming from archaeological sites allowed to make zooarchaeology and palaeoecology studies of the complete sequences of three sites dated from Upper Pleistocene: Caours (Somme) from the Eemian, Le Rozel (Manche) et Mutzig (Bas-Rhin) from the Early Weichselian. Large mammals teeth from Biache-Saint-Vaast (Pas-de-Calais), dated from the end of the Saalian, were also partially studied. The zooarchaeological research was mainly focused on the use of mortality profils and the determination of seasonnality. It was then possible to determine some general behavior, recurrent in several sites, as preference of cervids, selective transport of animals depending on the weight of the mammals, and intensive use with alimentary research marked by the collect of meat, marrow and tongue. Despite that, some behavior seem to be more specific, like a non-alimentary purpose of corpses with use of skin, fur and bones as retouchers, as well as preferential hunting based on age and/or sex of the individuals. Thus, Neandertalians' behavior from Northern France is characterized by a certain homogeneity, but also by a variability that results from the constant adaptation of their environment.
13

Mamíferos terrestres de maior porte e a invasão de cães domésticos em remanescentes de uma paisagem fragmentada de Mata Atlântica: avaliação da eficiência de métodos de amostragem e da importância de múltiplos fatores sobre a distribuição das espécies / Terrestrial large mammals and invasion of domestic dogs in remnants of an Atlantic Forest fragmented landscape: evaluation of the efficiency of sampling methods and of the importance of multiple factors on species distribution.

Karina Dias Espartosa 12 March 2009 (has links)
Nessa dissertação, avaliei a eficiência e congruência de métodos para amostragem de mamíferos de maior porte e investiguei a influência de fatores múltiplos correlacionados, comuns em paisagens fragmentadas, sobre a distribuição destes animais em remanescentes de Mata Atlântica. Através de amostragens padronizadas em 24 remanescentes florestais de uma paisagem rural com 49% de remanescentes florestais no Planalto Paulista e de um delineamento pareado, no capítulo 2 comparei o desempenho e a congruência de dois métodos (pegadas em parcelas de areia e armadilhas fotográficas) e de dois tipos de isca (banana e iscas de cheiro) para a estimativa da riqueza e taxa de ocorrência de mamíferos de maior porte. Ambos os métodos se mostraram adequados para o estudo destes animais em florestas tropicais e dos fatores que afetam sua distribuição em paisagens alteradas, pois (1) registram as espécies de menor porte e noturnas, (2) podem ser padronizados entre áreas heterogêneas, (3) apresentam desempenho semelhante no registro da maioria das espécies e da riqueza de espécies, e (4) refletem de maneira similar o padrão de ocorrência das espécies entre diferentes áreas. Frente às iscas de cheiro utilizadas, a banana foi a isca mais eficiente na amostragem tanto das espécies herbívoras/frugívoras quanto das espécies onívoras, destacando a necessidade da padronização das iscas utilizadas e do uso de iscas complementares ou de iscas que atraiam uma ampla gama de animais. Usando os dados obtidos com armadilhas fotográficas, avaliei quais fatores condicionam a presença e a freqüência de ocorrência de cães domésticos (capítulo 3) e de mamíferos de maior porte (capítulo 4) nos remanescentes. Esta avaliação foi realizada através da seleção de modelos de regressão construídos com base na relação causal entre os fatores estudados - que pode ser estabelecida a partir de como usualmente se dá a expansão das atividades humanas em florestas neotropicais - e comparados através do critério de informação AIC (The Akaike Information Criterion). Para o cão doméstico, foram considerados quatro fatores: extensão de estradas, quantidade de mata e número de cães domésticos no entorno, e qualidade da vegetação. Foi observada uma forte relação positiva entre o total de residentes e o total de cães domésticos no entorno dos remanescentes. Dentro dos remanescentes, o cão doméstico foi mais registrado do que sete das 11 espécies nativas, sua ocorrência foi mais bem explicada pela quantidade de cães no entorno, e sua freqüência de ocorrência pela diminuição da quantidade de mata no entorno, o que mostra a necessidade de controle populacional desta espécie no entorno de áreas naturais e da manutenção de áreas florestadas mais extensas, menos suscetíveis a entrada deste invasor. Para os mamíferos de maior porte, os fatores considerados foram: quantidade de mata e número de residentes no entorno dos remanescentes, distância à estrada de asfalto, freqüência de ocorrência de cães domésticos nos remanescentes, e qualidade da vegetação dos remanescentes. Os resultados demonstraram que, apesar da ampla variação na resposta das espécies a estes fatores, a distância a estradas de asfalto e a freqüência de ocorrência de cães domésticos, fatores que são correlacionados a disponibilidade de habitat e não são freqüentemente considerados, determinaram a distribuição de um número maior de espécies. A comunidade de mamíferos de maior porte encontrada é simplificada, dominada por espécies generalistas e com poucos dispersores e predadores de sementes e plântulas, o que pode levar a conseqüências negativas para outras espécies e para o funcionamento e regeneração das florestas remanescentes. Estes resultados sugerem que para a conservação de uma comunidade íntegra de mamíferos de maior porte na Mata Atlântica é necessário, não apenas a manutenção de grandes contínuos de mata nativa ou de paisagens com percentual alto de matas remanescentes, mas a redução drástica das perturbações associadas à ocupação e atividades humanas. O manejo e restauração de paisagens devem considerar a proximidade entre os remanescentes florestais e estradas, principalmente as asfaltadas e de alto tráfego, e a importância de campanhas de controle populacional e vacinação de cães domésticos. / In this master thesis, I evaluated the efficiency and congruence of methods for sampling large mammals, and investigated the influence of multiple and correlated factors, common in fragmented landscapes, on the distribution of these animals in Atlantic Forest remnants. Through standardized surveys at 24 forest remnants in a rural landscape with 49% of remaining forest in the Planalto Paulista and using a paired design, in chapter 2 I compared the performance and the congruence of two methods (tracks in sand plots and camera-trapping) and of two types of baits (banana and scent lures) for estimating richness and rate of occurrence of large mammals. Both methods are suitable for studying these animals in tropical forests as well as the factors that affect their distribution in disturbed landscapes, because (1) they record medium-sized and nocturnal species, (2) can be standardized among heterogeneous sites, (3) present similar performance for recording most species and richness, (4) reflect in similar ways the pattern of species occurrence among different sites. Compared with scent lures, banana was the most efficient bait for sampling herbivores/frugivores as well as omnivores, highlighting the need to standardize baits and use complementary baits or baits that attract a wide range of animals. Using camera-trapping data, I evaluated which factors determine the presence and the frequency of occurrence of domestic dogs (chapter 3) and of large mammals (chapter 4) in remnants. This evaluation was done through the selection of regression models buit based on the causal relationship among studied factors which can be established from the way expansion of human activities usually happens in neotropical forests and compared through the AIC, The Akaike Information Criterion. For the domestic dog, four factors were considerate: extension of roads, amount of forest and number of domestic dogs in the surroundings, and vegetation quality. It was observed a strong positive relationship between the total number of residents and the total number of domestic dogs in the surroundings. Inside remnants, the domestic dog was more frequently recorded than seven of the 11 native species, its occurrence was better explained by the number of dogs in the surroundings, and its frequency of occurrence by the reduction of the amount of forest in the surroundings, which indicates the need of population control of this invasive species in the surroundings of natural areas and of the maintenance of extensive forests areas that are less susceptible to the entrance of this invasive species. For native large mammals, the considered factors were: amount of forest and number of residents in the surroundings, distance from paved roads, frequency of occurrence of domestic dogs and vegetation quality. Results suggested that, despite the large variation in the responses of species to the studied factors, distance from paved roads and frequency of occurrence of domestic dog, factors that are correlated with habitat availability and are not frequently considered, determined the distribution of a larger number of species. The large mammal community found is simplified, dominated by generalist species and with few seed and seedling dispersers and predators, which can lead to negative consequences to other species and to forest functioning and regeneration. These results suggest that for conserving a complete large mammal community at the Atlantic Forest, not only the maintenance of large tracts of continuous forest or landscapes with high percentage of remaining forest is needed, but also a drastic reduction of disturbances associated with human activities and occupation. Landscape management and restoration should consider the proximity between forest remnants and roads, especially those that are paved and present high traffic, and the importance of campaigns of domestic dog population control and vaccination.
14

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

Fernanda Delborgo Abra 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
15

Paléoenvironnements et reconstitutions paléoclimatiques du Pléistocène moyen de Thaïlande et leur impact sur la biodiversité et la distribution des espèces : la contribution de la faune de vertébrés du gisement de Khok Sung (Province du Khorat) / Paleoenvironmental and paleoclimatic reconstructions of the Thai Middle Pleistocene and their impacts on the biodiversity and the species composition and distribution : the contribution of Khok Sung (Khorat province, Thailand) vertebrate community

Suraprasit, Kantapon 16 November 2015 (has links)
La sablière de Khok Sung, dans la province de Nakhon Ratchasima, qui a livré plus d'un millier de fossiles de mammifères et de reptiles (cranes, dents isolées et restes post-craniens), abrite la faune de vertébrés du Pléistocène la plus riche de Thaïlande. La faune mammalienne qui est décrite ici en détail, se compose d'au moins 18 espèces identifiées (12 genres), y compris un primate et des proboscidiens, rhinocéros, suidés, bovidés, cervidés et carnivores. Elle compte principalement des taxons encore représentés de nos jours, ainsi que quelques taxons globalement ou localement éteints. A partir des données paléomagnétiques et des comparaisons fauniques, l'âge de la faune de Khok Sung est estimé au Pléistocène Moyen tardif, vers 188000 ou 213000 ans. Par rapport aux autres faunes diversifiées du Pléistocène d'Asie du Sud Est, l'assemblage de Khok Sung est caractérisé par une association des taxons Stegodon-Ailuropoda, comparable en cela au site de Thum Wiman Nakin, ce qui supporte l'hypothèse selon laquelle le Nord Est de la Thaïlande était un corridor biogéographique appartenant à la route migratoire Sino-Malaise, entre la Chine du Sud et l'île de Java. L'analyse des isotopes stables du carbone à partir de l'émail des ongulés fossiles révèle la présence d'une partition de niches entre les méga-herbivores et au sein des cervidés. Les valeurs du d13C de l'émail suggèrent également que les ruminants ont consommé une grande quantité de plantes en C4, ce qui indique que les prairies à graminées étaient particulièrement répandues en Thaïlande à cette époque où les écosystèmes n'étaient pas encore soumis à l'influence anthropique. La mesure des isotopes stables de l'oxygène, obtenue par échantillonnage sérié de l'émail des dents de grands mammifères, et l'analyse du cénogramme de la localité de Khok Sung reflètent une importante variation saisonnière des précipitations et de la température, associée à des conditions climatiques relativement humides. / The Khok Sung sand pit, Nakhon Ratchasima province, has yielded the richest Pleistocene vertebrate fauna of Thailand, where more than a thousand fossil mammals and reptiles (skulls, isolated teeth, and postcranial remains) were recovered. The mammalian fauna, which is described in details hereby, consists of at least 18 identified species (12 genera), including a primate, proboscideans, rhinoceroses, suids, bovids, cervids, and carnivores, which are characterized by mostly extant elements associated to some completely and locally extinct taxa. The age of the Khok Sung fauna is tentatively attributed to the late Middle Pleistocene as either 188 or 213 ka, based on the paleomagnetic data and on the faunal comparisons. The Khok Sung mammal assemblage yields the Stegodon-Ailuropoda faunal association, most similar in composition to that of Thum Wiman Nakin, supporting the hypothesis that northeastern Thailand was a biogeographic gateway of the Sino-Malayan migration route from South China to Java. An analysis of stable carbon isotopes extracted from the tooth enamel of fossil ungulates reveals evidence of niche partitioning among megaherbivores and within cervids. The enamel carbonate d13C values also suggest a considerable amount of C4 plants in the dietary use of ruminants, indicating that grasslands had significantly expanded in Thailand at that time during which anthropic impacts on the ecosystems were absent. The stable oxygen isotope results, obtained from the serial sampling of large mammal enamel, combined with the cenogram analysis reflect significant seasonal variation in precipitations and temperature for Khok Sung, associated to a relatively humid climate.
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Leveraging big satellite image and animal tracking data for characterizing large mammal habitats

Oeser, Julian 07 September 2022 (has links)
Die zunehmende Verfügbarkeit von Satellitenfernerkundungs- und Wildtier-Telemetriedaten eröffnet neue Möglichkeiten für eine verbesserte Überwachung von Wildtierhabitaten durch Habitatmodelle, doch fehlt es häufig an geeigneten Ansätzen, um dieses Potenzial voll auszuschöpfen. Das übergeordnete Ziel dieser Arbeit bestand in der Konzipierung und Weiterentwicklung von Ansätzen zur Nutzung des Potenzials großer Satellitenbild- und Telemetriedatensätze in Habitatmodellen. Am Beispiel von drei großen Säugetierarten in Europa (Eurasischer Luchs, Rothirsch und Reh) wurden Ansätze entwickelt, um (1) Habitatmodelle mit dem umfangreichsten global und frei verfügbaren Satellitenbildarchiv der Landsat-Satelliten zu verknüpfen und (2) Wildtier-Telemetriedaten über Wildtierpopulationen hinweg in großflächigen Analysen der Habitateignung und -nutzung zu integrieren. Die Ergebnisse dieser Arbeit belegen das enorme Potenzial von Landsat-basierten Variablen als Prädiktoren in Habitatmodellen, die es ermöglichen von statischen Habitatbeschreibungen zu einem kontinuierlichen Monitoring von Habitatdynamiken über Raum und Zeit überzugehen. Die Ergebnisse meiner Forschung zeigen darüber hinaus, wie wichtig es ist, die Kontextabhängigkeit der Lebensraumnutzung von Wildtieren in Habitatmodellen zu berücksichtigen, insbesondere auch bei der Integration von Telemetriedatensätzen über Wildtierpopulationen hinweg. Die Ergebnisse dieser Dissertation liefern neue ökologische Erkenntnisse, welche zum Management und Schutz großer Säugetiere beitragen können. Darüber hinaus zeigt meine Forschung, dass eine bessere Integration von Satellitenbild- und Telemetriedaten eine neue Generation von Habitatmodellen möglich macht, welche genauere Analysen und ein besseres Verständnis von Lebensraumdynamiken erlaubt und so Bemühungen zum Schutz von Wildtieren unterstützen kann. / The growing availability of satellite remote sensing and animal tracking data opens new opportunities for an improved monitoring of wildlife habitats based on habitat models, yet suitable approaches for making full use of this potential are commonly lacking. The overarching goal of this thesis was to develop and advance approaches for harnessing the potential of big satellite image and animal tracking data in habitat models. Specifically, using three large mammal species in Europe as an example (Eurasian lynx, red deer, and roe deer), I developed approaches for (1) linking habitat models to the largest global and freely available satellite image record, the Landsat image archive, and (2) for integrating animal tracking datasets across wildlife populations in large-area assessments of habitat suitability and use. The results of this thesis demonstrate the enormous potential of Landsat-based variables as predictors in habitat models, allowing to move from static habitat descriptions to a continuous monitoring of habitat dynamics across space and time. In addition, my research underscores the importance of considering context-dependence in species’ habitat use in habitat models, particularly also when integrating tracking datasets across wildlife populations. The findings of this thesis provide novel ecological insights that help to inform the management and conservation of large mammals and more broadly, demonstrate that a better integration of satellite image and animal tracking data will allow for a new generation of habitat models improving our ability to monitor and understand habitat dynamics, thus supporting efforts to restore and protect wildlife across the globe.
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Land-use change, protected area effectiveness, and wildlife dynamics in post-Soviet European Russia

Sieber, Anika 30 May 2017 (has links)
Die Biodiversitätskrise des Anthropozäns wird vor allem durch vom Menschen bedingte Umweltveränderungen verursacht. Naturschutzgebiete sind ein globaler Eckpfeiler des Umweltschutzes und besonders wichtig für den Erhalt von Großsäugern. Fortschreitender menschlicher Einfluss sowie zunehmender Verlust und die Zerteilung von Lebensräumen innerhalb und außerhalb von Naturschutzgebieten beeinflussen deren Effektivität und Wert für den Umweltschutz stark, besonders in Zeiten sozioökonomischer und institutioneller Schocks mit reduzierten Ressourcen für den Umweltschutz. Der Zusammenbruch der Sowjetunion im Jahr 1991 war solch ein Schock und das Ziel dieser Doktorarbeit war es, besser zu verstehen, wie dieser Schock die Landnutzung, die Effektivität von Naturschutzgebieten und die Populationsdynamik von Wildtieren beeinflusst hat. Der europäische Teil Russlands bot sich deshalb als Untersuchungsgebiet an, da es eine vom Menschen stark beeinflusste Region ist, welche Lebensraum für Großsäuger aufweist sowie ein Netzwerk von Naturschutzgebieten besitzt, die über Langzeitdaten zur Biodiversität verfügen. Diese Doktorarbeit verwendete umfassende Datensätze und interdisziplinäre Ansätze, um die Veränderungen in Landnutzung, Jagddruck, Naturschutzgebieten, Lebensräumen und Populationsdynamiken von Wildtieren in post-sowjetischer Zeit zu beobachten und auszuwerten. Die Ergebnisse zeigen, dass der sozioökonomische und institutionelle Schock nach 1991 einen verringerten Landnutzungsdruck zur Folge hatte, bedingt durch die weit verbreitete Aufgabe von Landwirtschaft und generell abnehmende Raten von Waldeinschlag. Naturschutzgebiete spielten eine wichtige Rolle beim Schutz der Biodiversität und profitierten von vergrößerten Lebensräumen für Großsäuger. Wildtierpopulationsdynamiken waren in post-sowjetischer Zeit wesentlich beeinflusst von Landnutzungswandel und Jagddruck. Diese Forschungsergebnisse leisten einen wertvollen Beitrag zur Unterstützung des Biodiversitätsmonitorings. / The biodiversity crisis of the Anthropocene era is mainly caused by human-induced environmental changes such as land-use change and the overexploitation of wildlife. Protected areas are a cornerstone of the global conservation efforts and particularly important for preserving large mammals. Increasing human impact and continued loss and fragmentation of wildlife habitats inside and outside protected areas strongly affect their effectiveness and conservation value, especially during times of socio-economic and institutional shocks with reduced resources for nature conservation. The breakdown of the Soviet Union in 1991 was such a shock and the overall aim of this thesis was to contribute to a better understanding of how this shock affected land use, protected area effectiveness, and wildlife dynamics in European Russia. European Russia served as a representative area for such a study as it is a human-dominated region, which harbors large mammal species and a long-established network of scientific protected areas providing long-term biodiversity data. The overall aim of this thesis was assessed by using a broad range of data and interdisciplinary approaches to monitor and evaluate changes in land use and hunting pressure, protected areas, wildlife habitats, and species population dynamics in post-Soviet times. The results of this thesis revealed that the socio-economic and institutional shock after 1991 resulted in reduced land-use pressure due to widespread farmland abandonment and overall lowered rates of forest logging in European Russia. Protected areas played an important role in halting threats to biodiversity and benefitted from increased large mammals’ habitat within their zone of interaction. Wildlife dynamics were significantly affected by land-use change and hunting pressure in post-Soviet times. The findings of this thesis provide a valuable contribution to support biodiversity monitoring and overcome knowledge gaps on biodiversity conservation.

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