Teses em Zoologia (Doutorado) - PPGZOOL/ICB
URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/3419
O Doutorado Acadêmico foi criado em 1999 e pertence ao Programa de Pós-Graduação em Zoologia (PPGZOOL) do Instituto de Ciências Biológicas (ICB) foi consolidado como um convênio entre Universidade Federal do Pará (UFPA) e Museu Paraense Emílio Goeldi (MPEG).
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Navegando Teses em Zoologia (Doutorado) - PPGZOOL/ICB por Orientadores "COSTA, Maria Cristina dos Santos"
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Item Acesso aberto (Open Access) Avaliação dos efeitos da plantação de palmas (Elaeis guineensis) na conservação de anuros na Amazônia oriental(Universidade Federal do Pará, 2017-06-30) CORREA, Fabricio Simões; JUEN, Leandro; http://lattes.cnpq.br/1369357248133029; COSTA, Maria Cristina dos Santos; http://lattes.cnpq.br/1580962389416378In this thesis, we analyzed the effects of oil palm cultivation (Elaeis guineensis) on taxonomic and functional diversity of anurans in the eastern Amazon. In addition, we analyzed the response of anurans to environmental variation in oil palm plantations and surrounding forests. We surveyed for the presence of anurans in April 2012, 2015 and 2016, in 2100 m² plots through visual and acoustic searches. In April 2016, we also measured microclimatic (air temperature and humidity) and habitat structural variables (water body width and depth, leaf litter depth, canopy openness and number of trees) in both habitat types. We found higher functional diversity and species richness in forests, with difference in species composition and functional characters distribution between forests and oil palm plantations. Water body depth and width positively affected species richness and number of individuals, while water body depth and diurnal temperature influenced species composition in oil palm plantations. Only number of individuals was positively affected by diurnal temperature and nocturnal humidity in forests, while species composition and richness were not affected by any environmental variable in this habitat type. Our results make clear that conversion of forests to oil palm plantations negatively affects anurans taxonomic and functional diversity, making urgent the maintenance of forests surrounding the plantations as a way to reduce the negative impacts.Item Acesso aberto (Open Access) Turnover de anuros da Amazônia, perspectivas em multi escalas e habitats(Universidade Federal do Pará, 2015-03-31) BITAR, Youszef Oliveira da Cunha; JUEN, Leandro; http://lattes.cnpq.br/1369357248133029; COSTA, Maria Cristina dos Santos; http://lattes.cnpq.br/1580962389416378Understanding the processes involved in the species spatial distribution and the reasons leading to compositional dissimilarities among sites (turnover) have been studied on different scales and habitats. In the present study, we investigated the factors affecting frogs turnover from three different perspectives. In our first chapter of this thesis, entitled "Anuran beta diversity in the mosaic anthropogenic landscape in transitional Amazon", we tested how five environments, classified according to their human pressure, can structure frogs turnover. Sampling units (SU) on this first chapter are located in a ecotone between the Amazon and Cerrado biomes, also known as "Arc of deforestation". We observed that the conversion of forested areas (riparian forests) in open environments (monoculture of grains and rubber tree) result substitution of the original species and low turnover rates, something we can call faunal homogenization. However, the concept that turnover may change over structurally different environments is not new, specially if they have a strong degradation gradient, as found in the study area. Thus, in the second chapter of this thesis, "Species turnover in Amazonian frogs: Low predictability and large differences among terra firme forests", we seek to identify how environmental and spatial variation contribute to structure communities in well preserved terra-firme forests in Amazonia. The SU for this second chapter are located over three conservation units (National Forests of Amapá, Caxiuanã and Tapajós). We observed that, despite considered within the same class (terra firme), each community responds to a singular set of environmental variables. Testing the factors influencing species turnover over different scales, we observed that both the portion explained by environment and space had greater explanatory power (r2) in regional scales when compared within each of the areas (local scale). Another interesting result was that the spatial component showed no significant influence on Caxiuanã community, where only 3% of turnover was accounted for by any of the measured environmental factors. Finally, on third chapter titled "How differences in anuran reproductive modes can affect their turnover: Comparing scales and habitats", we discusses how frogs with different reproductive modes respond to environmental and spatial variations, comparing these processes in terra firme and varzea forests. Additionally, we evaluated species probability of occurrence along measured environmental gradients. The SU in this chapter are located in three areas of terra firme 12 forest (the same as in Chapter 2) and two areas of varzea (Sustainable Development Reserve Mamirauá and Amana). Species with aquatic oviposition were prevalent in varzea, while there was a higher proportion species laying on the vegetation in Caxiuanã and more species with terrestrial reproduction in Amapá and Tapajós when compared to the other areas. By dividing the species according to their reproductive modes, clearer response patterns were observed. Also, we can assert that changes in environmental characteristics appear as major turnover driver and are important in all scales, while the spatial distance is more evident at larger scales. Thus, we can conclude that in disturbed areas faunal homogenization decreases species turnover, due to the conversion of forests into open and less heterogeneous areas. Moreover, we also observed that even in areas within the same classification and without human disturbances, there are great differences in turnover partitioning patterns, which can be assigned to a specific set spatial and environmental factors inherent to each area, in addition to species with different reproductive modes.