11 research outputs found

    Fragmentação florestal: efeitos em múltipla escala sobre a diversidade de aves em remanescentes florestais no noroeste do Estado de São Paulo

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    A fragmentação florestal é uma das principais ameaças a diversidade de aves sendo responsável por grande parte das extinções de espécies em florestas tropicais. Os efeitos da fragmentação florestal sobre a diversidade de espécies em remanescentes devem ser analisados em diferentes escalas com a finalidade de uma melhor interpretação de suas conseqüências sobre cada espécie ou grupo de espécies. Desta forma, este estudo procurou responder três perguntas que geraram as hipóteses de trabalho desenvolvidas em cada capítulo. 1) Quais espécies ocorrem na região noroeste do estado de São Paulo? 2) Como a paisagem do entorno dos remanescentes florestais influencia a riqueza e os grupos funcionais de aves? 3) Na escala do fragmento, como as variáveis ambientais influenciam a riqueza de espécies e a distribuição dos grupos funcionais nos remanescentes florestais? As respostas dessas perguntas seguem um gradiente de relação, de um fator regional até o local. Foram registradas 328 espécies para a região. As origens dos registros permitiram supor que os exclusivamente históricos foram de espécies que não ocorram mais localmente. Essas espécies apresentaram uma forte relação com as categorias propostas, sendo que 75% delas possuem algum tipo de dependência com o ambiente florestal, 63% estão categorizadas como ameaçadas de extinção para o estado de São Paulo e 34% pertencem a algum centro de endemismo. Na escala da paisagem, a distância adotada como paisagem de entorno e os requerimentos ecológicos de cada grupo funcional são responsáveis pelas relações com os componentes da paisagem. Na escala do fragmento, as similaridades entre os remanescentes florestais de acordo com as variáveis estruturais e os grupos funcionais nem sempre foram concordantes. As relações positivas entre o tamanho de área e porcentagem de área nuclear com a riqueza...Forest fragmentation is one of the major threats to bird diversity and is responsible for most of the extinctions of species in tropical forests. The effects of forest fragmentation on the species diversity in forest remnants should be analyzed at different scales in order to a better interpretation of the consequences for each species or species groups. The presented thesis was therefore structured in three chapters that address questions which reflect these differente scales 1) Which species occur in the northwestern region of the state of São Paulo? 2) How influences the landscapes the species richness and the functional groups of birds? 3) How are species richness and distribution of functional groups in forest remnants influenced by environmental variables on the patch scale? The answers to these questions follow a gradient, of a regional to a local scale. The records of our assessment and former studies, performed in this region, include 328 species for the northwestern region, but show discrepancies in species composition between the former and the present status. Some species have thus apparently vanished regionally. We structured the records in three categories representing forest dependence, threat status, and endemism. The species that have regionally vanished show a strong relationship with the categories: 75% depend somehow on the forest habitat, 63% are categorized as endangered in the state of São Paulo, and 34% are endemic to four endemism centers. At the landscape scale, the surrounding landscape and the ecological requirements of each functional group describe the relations of bird functional groups and bird species richness to the components of the landscape. On patch scale the multivariate analysis showed that the similarities between remnants according structural variable and functional groups, sometimes disagree. The positive relationship... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Taxocenose de aves em um remanescente da Floresta com Araucária no Sudeste do Paraná, Brasil

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    Este trabalho teve por objetivo analisar a comunidade de aves de um remanescente florestal de pequeno porte (10 ha) localizado no município de Tijucas do Sul, estado do Paraná, nos domínios da Floresta com Araucária. Durante o período de novembro de 1999 a abril de 2001 foram realizadas 15 amostragens de dois dias de duração no qual foram utilizados os métodos de amostragem por captura com redes de neblina e observações visuais e auditivas. Foram registradas 118 espécies de 35 famílias. de acordo com a freqüência de ocorrência cerca de 44% das espécies foram consideradas pouco freqüentes. As guildas tróficas mais representativas foram aquelas compostas por espécies onívoras, seguidas pelas insetívoras de folhagem. O método de captura com redes ornitológicas obteve 501 capturas de 47 espécies. As espécies capturadas apresentaram abundâncias relativas variando de 0,31 a 13,16% e o índice de equitabilidade foi de 0,83, demonstrando que a taxocenose apresenta uma baixa dominância. A estrutura da taxocenose registrada é a esperada para um fragmento de pequeno porte, com a maior abundância de guildas e espécies generalistas e com a presença de um grande número de espécies com baixa frequência de ocorrência. Apesar disso, a composição específica com uma grande presença de espécies silvícolas demonstra que o remanescente desempenha um importante papel na manutenção de espécies dependentes dos ambientes florestais.In this study the community of birds in a small size remnant (10 ha) of Araucária forest, located in the city of Tijucas do Sul, Paraná was evaluated. During the period of November, 1999 to April 2001, 15 surveys had been carried, in which capture with mist nets and visual and aural contacts were used to estimate avian abundance and richness. We recorded 118 species of 35 families. According to the frequency of occurrence around 44% of species were considered with low frequency. When analyzed the trophics guilds, omnivorous and insectivorous of foliage were the most representative. By the capture method had been gotten 501 captures of 47 species. The capture species had relative abundances varying from 0.31 to 13.16% and the uniformity index was 0.83, demonstrating that the avian assemblage had a low dominance of some species. The structure of avian assemblage registered is expected for a small size remnant, with high relative abundance of generalists species and guilds, and the presence of a high number of species with low frequency of occurrence. Despite of, the specific composition presents a great number of species forest dependents showing that this forest remnant has a important role in the maintenance of species regionally.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Water quality of rural ponds in the extensive agricultural landscape of the Cerrado (Brazil)

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    The Brazilian Cerrado, one of the world’s 34 biodiversity hotspots, is today under increasing pressure from the intensification of agriculture, with the replacement of traditional extensive pastures by arable crops. Manmade ponds are currently widespread in rural areas of the Cerrado and provide many ecosystem services such as cattle watering, fish production, irrigation and erosion protection. As in other parts of the world, ponds are also likely to play a critical role in the conservation of freshwater biodiversity, although in the Cerrado there is still very little known about their biota. Good water quality, in particular the level of eutrophication, is a key factor in maintaining aquatic biodiversity at the regional scale. Therefore, we aimed here to assess the water quality of ponds in the Cerrado. We also assessed whether the main types of socioeconomic pond uses have an impact on their water quality. We focused on measures of primary production and conducted socioeconomic inquiries for 56 waterbodies in the Goia ˆnia Cerrado region (GO, Brazil) at the beginning of the 2012 dry season. Overall, differences in water quality appeared to be linked to the type of pond use. The trophic level, as indicated by the chlorophyll concentration and conductivity, was greater in fish ponds and seemed to be related to management practices such as fish feeding and the type of water supply, in particular relatively low inflow volume. This contrasted with ponds used for cattle watering in extensive agricultural landscapes characterized by a low trophic level potentially beneficial for regional biodiversity. Good water quality in pasture ponds may be maintained by spring water inflow or heavy precipitation. Overall, the water quality of the Cerrado ponds was good compared with the same type of waterbodies in other regions of the world. These results highlight the high potential of the Cerrado ponds in extensive agricultural landscapes to provide an important habitat for aquatic biodiversity. Biodiversity inventories and assessments are now needed to increase our knowledge of these waterbodies and inform management activities at the local and regional scale

    Guia de identificação das espécies de anfíbios (Anura e Gymnophiona) do estado de Goiás e do Distrito Federal, Brasil Central

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    O “Guia de Identificação das Espécies de Anfíbios (Anura e Gymnophiona) do Estado de Goiás e do Distrito Federal, Brasil Central” é um trabalho que busca promover a disseminação do conhecimento regional e popularizar o conhecimento sobre os anfíbios do Cerrado, sendo um instrumento de pesquisa útil, tanto para o leigo quanto para o pesquisador interessado. O guia está estruturado em seções que tratam da caracterização de 114 espécies de anfíbios (111 anuros e 3 gimnofionos) com informações disponíveis na literatura científica e dos próprios autores. A caracterização de cada espécie reúne informações sobre a localidade-tipo, a distribuição geográfica, os nomes populares, a caracterização morfológica do adulto e do girino e dados de história natural. São apresentadas imagens em vida das espécies e mapas de distribuição para o Estado de Goiás e Distrito Federal, além de uma chave dicotômica confeccionada a partir da seleção de algumas características morfológicas evidentes, que podem ajudar na identificação das espécies

    ATLANTIC BIRD TRAITS: a data set of bird morphological traits from the Atlantic forests of South America

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    Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morphological variation between and within species, and in how climate, topography, and anthropogenic pressures may explain and affect phenotypic variation. Because morphological data are not always available for many species at the local or regional scale, we are limited in our understanding of intra- and interspecies spatial morphological variation. Here, we present the ATLANTIC BIRD TRAITS, a data set that includes measurements of up to 44 morphological traits in 67,197 bird records from 2,790 populations distributed throughout the Atlantic forests of South America. This data set comprises information, compiled over two centuries (1820–2018), for 711 bird species, which represent 80% of all known bird diversity in the Atlantic Forest. Among the most commonly reported traits are sex (n = 65,717), age (n = 63,852), body mass (n = 58,768), flight molt presence (n = 44,941), molt presence (n = 44,847), body molt presence (n = 44,606), tail length (n = 43,005), reproductive stage (n = 42,588), bill length (n = 37,409), body length (n = 28,394), right wing length (n = 21,950), tarsus length (n = 20,342), and wing length (n = 18,071). The most frequently recorded species are Chiroxiphia caudata (n = 1,837), Turdus albicollis (n = 1,658), Trichothraupis melanops (n = 1,468), Turdus leucomelas (n = 1,436), and Basileuterus culicivorus (n = 1,384). The species recorded in the greatest number of sampling localities are Basileuterus culicivorus (n = 243), Trichothraupis melanops (n = 242), Chiroxiphia caudata (n = 210), Platyrinchus mystaceus (n = 208), and Turdus rufiventris (n = 191). ATLANTIC BIRD TRAITS (ABT) is the most comprehensive data set on measurements of bird morphological traits found in a biodiversity hotspot; it provides data for basic and applied research at multiple scales, from individual to community, and from the local to the macroecological perspectives. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or teaching and educational activities. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ
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