999 resultados para Atlantic rainforest Northeastern Brazil


Relevância:

100.00% 100.00%

Publicador:

Resumo:

The effects of disturbances on plant community structure in tropical forests have been widely investigated. However, a majority of these studies examined only woody species, principally trees, whereas the effects of disturbances on the whole assemblage of vascular plants remain largely unexplored. At the present study, all vascular plants < 5m tall were surveyed in four habitats: natural treefall gaps, burned forest, and their adjacent understorey. The burned area differed from the other habitats in terms of species composition. However, species richness and plant density did not differ between burned area and the adjacent understorey, which is in accordance to the succession model that predict a rapid recovery of species richness, but with a different species composition in areas under moderate disturbance. The treefall gaps and the two areas of understorey did not differ among themselves in terms of the number of individuals, number of species, nor in species composition. The absence of differences between the vegetation in treefall gaps and in understorey areas seems to be in agreement with the current idea that the species present in treefall gaps are directly related to the vegetation composition before gap formation. Only minimal differences were observed between the analyses that considered only tree species and those that considered all growth habits. This suggests that the same processes acting on tree species (the best studied group of plants in tropical forests) are also acting on the whole assemblage of vascular plants in these communities.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper presents a taxonomic study of taxa of the red algae genus Herposiphonia (Ceramiales) occurring on Maracaja Reef in the Coral Reefs Environmental Protection Area (CREPA - rea de Proteo Ambiental dos Recifes de Corais) in Rio Grande do Norte State, along the northeastern coast of Brazil. The CREPA comprises coastline and continental shelf areas of the municipalities of Touros, Rio do Fogo, and Maxaranguape and includes sand dunes, coastal lagoons, and the adjacent shoreline and offshore reefs. Detailed morphological studies were made, considering recent taxonomic criteria for species delimitation of Herposiphonia, and five species were identified: H. delicatula, H. nuda, H. parca, H. secunda, and H. tenella, thus increasing the number of species in the genus from three to six. Herposiphonia delicatula and H. parca represent new occurrences for Brazil, and H. nuda is reported for the first time for the Atlantic Ocean.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The Brazilian Atlantic Rainforest is a highly heterogeneous ecosystem comprising large numbers of tropical and subtropical habitats favorable to the development of cyanobacteria. Studies on cyanobacteria in this ecosystem are still rare, however, especially those involving unicellular and colonial types. The high biodiversity and endemism of this biome has been extremely impacted and fragmented, and less than 10% of its original vegetation cover remains today. We describe here a new species of a colonial cyanobacteria, Lemmermanniella terrestris, found on dry soils in a subtropical region of the Atlantic Rainforest in the municipality of Canania in southern So Paulo State, Brazil. This new taxon demonstrated all of the diacritical features of the genus Lemmermanniella but, unlike the other species of the genus, it was growing on the soil surface and not in an aquatic environment. A set of morphological features, including colonies composed of subcolonies, and cell dimensions, shapes and contents distinguish it from other species of the genus. Considering that species of Lemmermanniella are found in very distinct habitats (such as thermal and brackish waters) and that they maintain the same life cycle described for the genus in all of those environments, the morphological structures of the colonies can be used as reliable markers for identifying the genus, and its species differ primarily in relation to the habitats they occupy.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new species of the tree toad genus Dendrophryniscus is described from a rainforest habitat at Parque Nacional de Serra das Lontras, municipality of Arataca, southern Bahia, Brazil. Dendrophryniscus oreites sp. nov. is related to the Atlantic forest brevipollicatus group by hand morphology, skin texture, ventral coloration and bromelicolous habits. The new species differs from related species by having a larger size, warty skin, inner finger reduced with presence of a dark nuptial pad in males, and a yellowish coloration with discrete dorsal pattern. This discovery highlights the importance of southern Bahia in terms of conservation, and for our understanding of the evolution of the frog diversity within the Atlantic Rainforest.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Long-term conservation in biodiversity hotspots depends on the recovery of communities in secondary forest fragments. In most cases, however, recovery strategies for these areas are based only on passive restoration. It is therefore necessary to determine the efficiency of such strategies. In this study, we assess the efficiency of passive restoration on a 567-ha 28-yr-old fragment of Atlantic Rainforest in Northeastern Brazil. We measured richness, composition, abundance and biomass of a lizard taxocene and also vegetation structure and availability of several microhabitat descriptors in 18 plots of this secondary forest. We then compared them with measures in 29 plots from two neighboring reference sites. Species richness, abundance, biomass and microhabitat descriptors availability inside the secondary fragment did not differ from reference sites. However, composition and vegetation structure showed small differences. Some forest specialist lizards, which should be a focus of conservation efforts in fragmented landscapes of the Atlantic Rainforest, were not found in the fragment and data indicate that this was not due to sampling or a lack of suitable habitat or microhabitat. In the presence of preserved source sites, passive restoration may be a cheap and effective way to recover lizard taxocenes of the Atlantic Rainforest. Some of the species may need to be re-introduced to accelerate the full recovery of original composition of lizard taxocenes in secondary Atlantic Rainforests.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Cientfico e Tecnolgico (CNPq)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A fauna de Ephemeroptera, Plecoptera e Trichoptera associadas ao folhio em um riacho do sudeste do Brasil foi estudada com o objetivo de responder s seguintes questes: 1) A riqueza e a composio faunstica de EPT difere entre os dois mesohabitats (corredeira-remanso) mesmo quando associadas ao mesmo substrato, folhio? 2) A similaridade da fauna de EPT entre os dois mesohabitas muda temporalmente? 3) A estrutura funcional de EPT difere entre os dois mesohabitats (corredeira-remanso)? Para responder essas questes, coletas mensais, de novembro de 1999 a junho de 2000, foram feitas no Ribeiro Bocaina com rede D (10 acmulos de folhas em remanso e 10 em corredeira). A fauna de EPT do Ribeiro Bocaina foi mais diversificada e mais abundante no folhio em corredeira do que no folhio em remanso, no entanto, quando a riqueza foi padronizada para o mesmo nmero de indivduos essa se tornou similar para as duas condies. A fauna de EPT foi bastante diferente entre os dois mesohabitats, tanto em termos da composio faunstica quanto em termos funcionais. Isso provavelmente ocorreu devido s diferenas de velocidade da gua, no tempo de residncia do folhio e na taxa de oxignio da gua entre os dois mesohabitats.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Comunidades de Ephemeroptera, Plecoptera e Trichoptera (EPT) em substrato rochoso foram estudadas em dois riachos do Parque Estadual Intervales. Coletas com um amostrador de Surber (10 subamostras aleatrias, 1 m) foram feitas mensalmente de setembro de 1999 a setembro de 2000 e trimestralmente de dezembro de 2000 a setembro de 2001 nos Ribeires Bocaina e gua Comprida. A fauna de EPT do Ribeiro Bocaina foi mais diversificada e mais abundante do que a do Ribeiro gua Comprida. A fauna de EPT foi bastante diferente entre os dois riachos, tanto do ponto de vista da composio faunstica quanto do ponto de vista funcional. Os resultados indicaram que no houve um padro sazonal claro da variao temporal da densidade.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The upper portion of the Rio Guaratuba, located in the Serra do Mar coastal range of Southeastern Brazil, shows biological and geological evidences of being captured and diverted away from its original course in the direction of the Parana River Basin to become a coastal river due to the Quaternary activity of NW-trending faults. Despite draining directly to the Atlantic Ocean, the upper portion of the Guaratuba still maintains an ichthyofauna that is typical of the adjoining Parana River Basin rather than the characteristic fish fauna of the Brazilian coastal drainages. The fish fauna of the upper Guaratuba is an evident testimony of the tectonic process that allowed the faunal interchange between the upland basins and the coastal drainages that probably has been taking place in Southeastern Brazil throughout the long geological history of the passive Brazilian continental margin.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We describe a new species of Ischnocnema from Santa Teresa, in the Atlantic Rainforest of the State of Espirito Santo, Brazil. Ischnocnema abdita sp. nov. is a member of the Ischnocnema lactea species series; it differs from other Ischnocnema mainly by presenting small size (adult male SVL 15.7 [plus or minus] 0.49 mm; range 15.0-16.8 mm); small discs on fingers I and II, and elliptical, wider than long, moderate sized discs on fingers III and IV; and finger I slightly smaller than finger II. The new species closely resembles Ischnocnema bolbodactyla, differing from it by presenting upper and lower margins of iris red in life; inguinal region with many yellow blotches in life; posterior region of belly and ventral surfaces of thighs, shanks, and feet roughly marbled with large pale yellow blotches; and hidden dorsal area of thighs dark brown with few large pale yellow blotches.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Because algae are primarily aquatic, it seems almost paradoxical that there Should exist a relatively diversified soil flora where aerophytic cyanoprokaryotes are especially abundant. However, there appear to be relatively few studies oil this topic. This paper aims to improve the taxonomic knowledge oil the chroococcalean and oscillatorialean cyanoprokaryote flora in tropical regions. Samples of cyanoprokaryotes were collected in the rainforest region of the So Paulo State, Brazil. Data oil cyanoprokaryote mass type and color, substratum type, air and mass temperature and humidity, pH and absolute and relative irradiance were collected. The study revealed the presence of 24 species belonging to the orders Chroococcales and Oscillatoriales (12 species each). Aphanothece (four species) was the most species-rich genus. Overall, taxonomic resolution at the species level based oil morphological and morphometric data can still be problematic.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A dieta de uma populao de jaguarundi (Puma yagouaroundi) (Geoffroy, 1803) (Carnivora, Felidae) foi estudada entre novembro de 2000 e novembro de 2001, em 24,9 km de mosaico de Mata Atlntica secundria e reflorestamento de eucalipto na Serra de Paranapiacaba, So Paulo, Brasil. A anlise das 26 amostras fecais e regurgitadas, obtidas em 570.1 km de percurso, indicou o consumo de 19 itens alimentares em um total de 74 ocorrncias de presas. Pequenos mamferos foram os itens mais frequentemente encontrados na dieta (42,5%), seguidos por aves (21%), rpteis (14%) e mamferos de tamanho mdio (3%). A porcentagem de ocorrncia (PO) sugere que a dieta concentra-se, principalmente, em pequenos roedores (30%) e aves (21%). Foi tambm registrada a predao sobre serpentes da famlia Viperidae. A amplitude de nicho alimentar padronizada (Bsta = 0,76) mostra uma dieta generalista, entretanto, os dados sugerem que o jaguarundi consome principalmente pequenos vertebrados (mamferos, aves ou rpteis), sobretudo, espcies terrestres.