Tese

Padrões de diversidade, ocupação e coexistência de mamíferos terrestres na região neotropical

Community structure and diversity result from a complex and dynamic phenomenon, determined by a large number of processes in space and time, which are driven by environmental conditions, spatial factors, resource availability, and species interactions, including competition and predation. This study...

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Autor principal: SANTOS, Fernanda da Silva
Grau: Tese
Idioma: por
Publicado em: Universidade Federal do Pará 2019
Assuntos:
Acesso em linha: http://repositorio.ufpa.br/jspui/handle/2011/11249
Resumo:
Community structure and diversity result from a complex and dynamic phenomenon, determined by a large number of processes in space and time, which are driven by environmental conditions, spatial factors, resource availability, and species interactions, including competition and predation. This study used the terrestrial mammal group as a model to investigate part of the processes shaping communities, and to understand patterns of diversity, occupancy, and coexistence in the Neotropical forests. Data from a long-term camera trapping monitoring of terrestrial vertebrates across eight protected area sites were combined. The study sites comprise eight areas distributed through six countries (Costa Rica [1], Panama [1], Ecuador [1], Peru [2], Suriname [1] e Brazil [2]), and include both intact forest and fragmented forest landscapes. Firstly, β diversity was estimated among the eight mammal communities to identify: which sites and species contributed to differences in the variation of community composition (LCBD and SCBD, respectively); which process (species replacement or richness difference) explain the observed β-diversity patterns; and which factors affect local contribution (LCBD) and species contribution (SCBD) to β diversity. Posteriorly, data from five sympatric cat species [jaguar (Panthera onca), puma (Puma concolor), ocelot (Leopardus pardalis), jaguarundi (Herpailurus yagouaroundi) and margay (Leopardus wiedii)], that potentially occur across the eight sites, were used to examine mechanisms that allow coexistence among ecologically similar species. Finally, data from one of the sites was used to test the hypothesis that terrestrial mammals, mainly frugivores and granivores, move seasonally as a response to resource availability fluctuation (e.g., water and fruits) between rainy and dry seasons in a terra-firme forest. The results indicated that fragmented forests contribute more to β diversity than intact forest sites, and that variation in species composition is determined by richness difference rather than replacement. The eleven species ranked as the most important in structuring the communities were also the ones with the highest abundance variation among sites. Regarding felids’ coexistence, the study reveals an apparent spatial and temporal partitioning for most species pairs, with prey abundance being more important than species interactions to the local occurrence and spatial distribution of Neotropical forest cats. Concerning seasonal dynamics, only three species presented differences on occupancy between dry and rainy seasons, while the other analyzed species did not seem to move as a response to variation in water and food availability. In summary, the results provide a broad characterization of terrestrial mammals occurring in the Neotropical region, assessing their conservation status, factors that influence their occurrence, as well as the spatial and temporal patterns of several felid species along eight Neotropical protected forests.