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Altitudinal gradients represent useful tool for investigating diversity patterns and processes affecting species richness and turnover along steep gradient of conditions at relatively small scale. The aim of my study was to compile a complete checklist of birds for elevational gradient of Mt. Cameroon rainforests (300 - 2300 m a.s.l.) and to analyse distribution of species diversity, species turnover, elevational ranges and relationships between elevational distribution of species and their range size, body weight or diet type. Species richness on the elevational gradient of Mt. Cameroon decline monotonically with some plateau at 600 - 1000 m a.s.l. Changes of community composition along the gradient are caused mainly by species turnover at low elevations, which contrast to pattern above 1200 m a.s.l. where the betadiversity is influenced mainly by continual species loss (nestedness). Species elevational ranges increase with increasing elevation, which is in agreement with elevational Rapoport's rule. Species breeding at higher elevations have smaller geographical ranges, restricted to isolated islands of montane rainforests. Numbers of insectivorous species are rapidly decreasing with increasing elevation, proportion of nectarivorous species is rather invariable and number of granivorous species...

Submitted by GABRIELLE CRISTINA BECA (gabrielle.beca@gmail.com) on 2016-02-25T20:15:26Z No. of bitstreams: 1 dissertacao_gabriellebeca.pdf: 1615879 bytes, checksum: 8a5c0dc6a5fd4b14d63387382f7f3ae9 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-02-26T18:04:40Z (GMT) No. of bitstreams: 1 beca_gc_me_rcla.pdf: 1615879 bytes, checksum: 8a5c0dc6a5fd4b14d63387382f7f3ae9 (MD5) / Made available in DSpace on 2016-02-26T18:04:40Z (GMT). No. of bitstreams: 1 beca_gc_me_rcla.pdf: 1615879 bytes, checksum: 8a5c0dc6a5fd4b14d63387382f7f3ae9 (MD5) Previous issue date: 2016-01-29 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A crescente demanda por fontes alternativas de energia tem contribuído para o aumento da produção de biocombustíveis, levando a fragmentação dos habitats naturais. No entanto, paisagens naturais imersas em matrizes agrícolas podem reter uma diversidade de espécies considerável, mas os efeitos da mudança no uso do solo para a produção de biocombustíveis sobre a persistência das espécies nessas paisagens ainda permanecem incertos. A Mata Atlântica, ecossistema mais fragmentado do Brasil, tem apenas cerca de 12% de sua cobertura vegetal original. A maioria destes remanescentes estão distribuídos em fragmentos pequenos e isolados devido à expansão agrícola, especialmente pela monocultura de cana-de-açúcar. No presente estudo examinamos a riqueza e a composição de mamíferos de médio e grande porte, e quantificamos a contribuição da cobertura florestal, da área estrutural e da quantidade de borda sobre a persistência desses animais. Amostramos 20 paisagens fragmentadas, em um gradiente de cobertura florestal (3% a 96%), imersas em plantações de cana-de-açúcar. Registramos apenas 50% das espécies esperadas de mamíferos de médio e grande porte em todas as 20 paisagens, em comparação com o maior remanescente de floresta semidecídua, o "Parque Estadual Morro do Diabo". Isso nos mostra que esses remanescentes de Mata Atlântica estão altamente empobrecidos, restando apenas25% de espécies especialistas florestais, e a maioria dos mamíferos registrados são espécies generalistas, exóticas e típicas de cerrado. A cobertura florestal foi importante para explicar apenas a presença de alguns ungulados e um roedor de médio porte. As comunidades de mamíferos responderam à substituição de espécies entre as paisagens, que representou 94% da β-diversidade total. Nosso estudo é novo em mostrar que a riqueza de mamíferos não foi afetada pela quantidade de habitat. É importante implementar medidas eficazes de conservação das áreas naturais em paisagens agrícolas, a fim de desenvolver medidas de restauração da cobertura florestal dos fragmentos, pois estes são cruciais para manter populações viáveis de espécies que dependem da floresta e ainda persistem nesses ambientes modificados. / The growing demand for alternative energy sources has contributed to increased biofuel production, leading to fragmentation of natural habitats. However, natural landscapes immersed in agricultural matrices can retain a considerable diversity of species, but the effects of the change in land use for the production of biofuels on the persistence of the species in these landscapes remain unclear. The Atlantic Forest, the most fragmented ecosystems in Brazil, has only about 12% of its original vegetation cover. The most of these remnants are distributed in small and isolated fragments due to agricultural expansion, especially by the sugarcane monocultures. In the present study we examined the richness and composition of medium and large sized mammals, and quantify the contribution of the forest cover, the structural area and the edge amount over persistence of these animals. We sampled 20 fragmented landscapes on a forest cover gradient (3% to 96%), immersed in sugarcane plantations. We recorded only 50% of expected species of medium and large sized mammals in all the 20 landscapes, compared to the largest remnant of semideciduous forest, the "Morro do Diabo State Park". This shows that the Atlantic Forest remnants are highly depleted, with only 25% of forest-specialist species and most of the mammals registered are generalist species, exotic and typical from savana. Forest cover was important to explain only the presence of some ungulates and a medium sized rodent. The mammal communities responded to a high turnover of species between the landscapes, which represented 94% of the total β- diversity. Our study is novel in showing that mammal richness was not affected by the habitat amount. It is important to implement effective conservation measures in natural areas in agricultural landscapes in order to develop measures of restoration of forest cover of the fragments, because they are crucial to maintain viable populations of forest-dependent species and still persist in these modified environments. / FAPESP: 2013/21939-3

Oak habitats are rich in saproxylic species, but the habitat is declining with loss of diversity due to encroachment which decrease the vitality of oaks. The present explorative study compared results from a study conducted in 1994, with present species communities to observe if there has been change in species composition and what factors that can explain species diversity and composition. The results revealed that the overall species composition between 1994 and 2018 has changed. There were 130 species recorded in 2018 compared to 108 species in 1994 (31 new species were recorded in 2018, and 9 species lost from the study in 1994). There was a high species turnover recorded per individual tree, and the species composition between the living and encountered dead trees did not differ. Species composition was affected by canopy cover, and trunk circumference (CCA P-value 0.001 and 0.014 respectively). Unlike 1994, there were no variables in 2018 that could explain the association with species numbers. Warmer conditions recorded during the sampling period have probably led to increased flight activity of beetles and therefore increasing chances of capturing more species and individuals. The warmer conditions possibly shadowed the effects of the explanatory variables in explaining the changes in species numbers. Perhaps the change in species composition could also be attributed to existing management interventions that may be supporting an increasing species number of saproxylic beetles, however no strong conclusions could be drawn. Management interventions such as the recruitment of new oaks should be encouraged and intensified in order to provide habitats and support stable populations as the loss of oaks may lead to increased risk of extinction of the saproxylic beetles in the study area.

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Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2018-04-11T11:57:10Z No. of bitstreams: 2 Dissertação - Lucas Pereira Martins - 2018.pdf: 2113878 bytes, checksum: 4c38a4d425f42506d50aa62bf6661c3f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-04-12T11:22:54Z (GMT) No. of bitstreams: 2 Dissertação - Lucas Pereira Martins - 2018.pdf: 2113878 bytes, checksum: 4c38a4d425f42506d50aa62bf6661c3f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-12T11:22:54Z (GMT). No. of bitstreams: 2 Dissertação - Lucas Pereira Martins - 2018.pdf: 2113878 bytes, checksum: 4c38a4d425f42506d50aa62bf6661c3f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-15 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Understanding how species interact with each other is essential to advance our knowledge on community ecology. However, there are still gaps regarding how interspecific interactions affect and are affected by the variation in the composition of species that constitute the ecological networks. In particular, studies of beta diversity are interesting to understand how sets of biotic filters may affect species’ geographic distribution and persistence on communities. Another interesting question is if variations in species composition may cause changes on how ecological networks are structured. In this dissertation, we propose to evaluate patterns of beta diversity and structure on insect-plant interaction networks. Specifically, in the first chapter we aimed to test if beta diversity is affected by the trophic level to which the assemblage belongs, and by the degree of specialization of species at higher trophic levels to their host species. For this, we used a tritrophic system comprising plants of the family Asteraceae, endophagous herbivores and parasitoids sampled in remnants of Brazilian Cerrado. Our main results show that total beta diversity of parasitoids (higher trophic level) was lower than those of the other trophic levels, while there was no difference between total beta diversity of plants and herbivores. Furthermore, the degree of specialization of the assemblages of herbivores and parasitoids was positively associated to the beta diversity of these groups. In the second chapter, we evaluated if species beta diversity among sites affects dissimilarity in network structure, and if this relationship changes across time. Overall, the relationship between spatial beta diversity and dissimilarity in plant-herbivore network structure was context-dependent, thus indicating that different ecological processes (i.e., niche-based and neutral) may drive the organization of antagonistic networks across time. / Compreender como as espécies interagem entre si é essencial para avançar o nosso conhecimento em ecologia de comunidades. No entanto, ainda existem lacunas no que se refere a como interações interespecíficas influenciam e são influenciadas pela variação na composição de espécies que constituem as redes ecológicas. Em particular, estudos de diversidade beta são interessantes para entender como conjuntos de filtros bióticos podem influenciar a distribuição geográfica e persistência de espécies nas comunidades. Outra questão interessante é se variações na composição de espécies podem causar mudanças no modo como redes ecológicas são estruturadas. Nesta dissertação, propomos avaliar padrões de diversidade beta e estrutura de redes de interações inseto-planta. Especificamente, no primeiro capítulo visamos testar se a diversidade beta é influenciada pelo nível trófico ao qual a assembleia pertence, e pelo grau de especialização de espécies de níveis tróficos superiores às suas espécies hospedeiras. Para isso, utilizamos um sistema tritrófico composto por plantas da família Asteraceae, herbívoros endófagos e parasitoides amostrado em remanescentes de Cerrado brasileiro. Nossos principais resultados demonstram que a diversidade beta total de parasitoides (nível trófico superior) foi menor do que a dos demais níveis tróficos, enquanto que não houve diferença entre a diversidade beta total de plantas e herbívoros. Além disso, o grau de especialização das assembleias de herbívoros e parasitoides foi positivamente relacionado à diversidade beta destes grupos. No segundo capítulo, avaliamos se a diversidade beta de espécies entre locais influencia a dissimilaridade na estrutura de redes ecológicas, e se esta relação muda através do tempo. De modo geral, a relação entre diversidade beta espacial e dissimilaridade na estrutura de redes planta-herbívoro foi contexto-dependente, indicando assim que diferentes processos ecológicos (i.e., baseados em nicho e neutros) podem determinar a organização de redes antagonistas através do tempo.

Submitted by Lara Gomes Melchior null (lahtuti@hotmail.com) on 2016-04-14T21:11:04Z No. of bitstreams: 1 Mestrado Lara Versão Final.pdf: 949503 bytes, checksum: 2675776db95f4fd4b4d6542497c65b45 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-15T13:12:06Z (GMT) No. of bitstreams: 1 melchior_lg_me_sjrp.pdf: 949503 bytes, checksum: 2675776db95f4fd4b4d6542497c65b45 (MD5) / Made available in DSpace on 2016-04-15T13:12:06Z (GMT). No. of bitstreams: 1 melchior_lg_me_sjrp.pdf: 949503 bytes, checksum: 2675776db95f4fd4b4d6542497c65b45 (MD5) Previous issue date: 2016-03-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A escolha da unidade amostral e extensão da área de estudo é crucial para a compreensão dos processos e mecanismos influenciando os padrões de distribuição da biodiversidade. Dependendo da escala espacial escolhida, os padrões de distribuição serão influenciados por processos ecológicos e biogeográficos diferentes. Neste trabalho, nós alternamos as unidades amostrais e extensões da área estudada (corpos d’água em um município, corpos d’água em uma ecoregião, municípios em uma ecoregião e municípios na área total de estudo) para avaliar a importância relativa das variáveis ecológicas e biogeográficas na diversidade beta de anuros na Floresta Atlântica Brasileira. Para isso, nós parcionamos a diversidade beta total nos componentes substituição espacial de espécies e aninhamento. Nós observamos que, mantendo a mesma unidade amostral e aumentando a extensão da área de estudo, os valores da substituição espécies aumentam. Por outro lado, mantendo a mesma extensão e aumentando a unidade amostral, os valores da substituição de espécies diminuem. Além disso, nossos resultados concordam que a importância relativa dos fatores ecológicos e biogeográficos na diversidade beta de anuros é dependente da escala espacial. Considerando as menores unidade amostral e extensão, as variáveis ambientais e distância geográfica se alternam na importância relativa associada aos valores de diversidade beta, enquanto que, em escalas espaciais maiores, as ecoregiões passam a ter uma importância relativa maior. / The selection of the sampling unit and extension of the study area is crucial for understanding the processes and mechanisms influencing biodiversity distribution patterns. Depending on the chosen scale, patterns of distribution will be influenced by different ecological and biogegraphical processes. Here, we alternate the sample units and extensions of the study area (water bodies in a municipality, water bodies in an ecoregion, municipalities in an ecoregion, and municipalities in total area of study) to assess the relative importance of ecological and biogeographical factors in the beta diversity of frogs in the Brazilian Atlantic Forest. We partitioned total beta diversity into two additive components, spatial species turnover and nestedness. We found that considering the same sample unit and increasing the extent of the study area the turnover values increased. On the other hand, considering the same extension and increasing the sampling unit, the turnover values decreased. Furthermore, our results agree that relative importance of the ecological and biogeographical processes in frog beta diversity is dependent on spatial scales. Considering the smallest sampling unit and extension, environmental variables and geographic distance alternated in their relative importance associated with beta diversity, while at largest spatial scales, ecoregions showed higher values of relative importance.

The aim of this thesis is to describe the changes of bird species diversity along elevation gradient on six mounts in Cameroon and nearby Bioko island. The results of the analyses confirm most of the defined hypotheses, especially they show that species diversity declines with altitude and rises with area. Cluster analysis shows the similarity of individual mountains in particular altitude zones. Despite the original hypothesis, mount Cameroon is found to be most similar to mount Kupé, although high mountain assemblages of mount Cameroon and Bioko island are very alike as well. The absolutely highest diversity was detected on mount Cameroon and mount Kupé, but above 2100 m above sea level mounts Oku and Manenguba are the most diverse. The results of this thesis contribute to a clearer notion about factors influencing species diversity; however, more thorough data (particularly from mount Nlonako) and data extension for e.g. bird abundance would enrich the study and it would enable us to perform more detailed diversity analysis, especially an analysis of competition relationship among species. Key words Species diversity, Cameroon, bird assemblages, elevational gradient

The aim of this thesis is to describe the changes of bird species diversity along elevation gradient on six mounts in Cameroon and nearby Bioko island. The results of the analyses confirm most of the defined hypotheses, especially they show that species diversity declines with altitude and rises with area. The absolutely highest diversity was detected on mount Kupé and mount Cameroon, but above 2100 m above sea level mounts Oku and Manenguba are the most diverse. Other analysis showed that the biggest changes in beta diversity of bird assemblages along altitudinal gradients are on the lowest elevational belts which are on the edges of a degraded habitats and continuous undisturbed forests. Other important changes in bird assemblages happen around altitude 1200 m, where the assemblages of lowland rainforest change to assemblages of mountain forest. Analyses of affinity of bird species to forest habitat showed that the most affined assemblages to the forest are those found on mounts Kupé and Rata. On the other hand bird assemblages on mounts Manenguba and Oku are the one of least affined to the forest biotope. Analysis of habitat generalism and specialism did not show the expected outcome and for clearer results the design of analysis needs to be improved. The results of this thesis contribute to a...

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