162 resultados para mata brejosa de galeria


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Protocols for rapid habitat evaluation and the biotic indices used in biomonitoring of streams in Brazil provide useful information about water quality and modifications in the ecosystem. However, the interpretation of their results is limited. Previous studies pointed out the low sensitivity of those indices to measure the quality of low-order streams, since they only measure organic impacts. Environmental degradation of these streams is mainly related to impacts caused by landscape change, such as erosion, siltation, channel change, loss of riparian vegetation, and reduction in water flow. The streams of the Serra do Japi are under some of these impacts, caused by agricultural activities. In this study, we evaluated whether the reduction of natural characteristics in these environments would decrease water quality. The Protocol of Habitat Diversity was affected by the impacts of agricultural activities. However, the other three biotic indices: Biological Monitoring Working Party Score System, Average Score Per Taxon, and Index of Benthic Community were not as sensitive to those impacts, since they all indicated a high water quality. An adaptation of the attributes and the scoring system is suggested for defining better policies for the conservation of this area.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this study was to determine the effect of nitrogen (N) and the phosphorus (P) in seedlings of Amburana cearensis planted in areas occupied by Brachiaria decumbens, in an Oxisol, which originally had a Dense Savanna and in a Plinthic surrounding a Gallery Forest. We evaluated the response of A. cearensisgrowth and survival in the absence and doses of -1 10, 20 and 40 kg ha N, as urea and absence and doses of 10, 20 and -1 40 kg ha P, in the form of triple superphosphate in a randomized complete block design. We evaluated the stem diameter at four, eight and twelve months after planting. At the end of the first year were evaluated crown diameter and survival. According to the classification proposed in this study the growth of A. cearensis can be considered very slow in the Oxisol, regardless of fertilization, very slow when fertilized with N in the Plinthic and slow when fertilized with P. Despite the lower growth in Oxisol, the A. cearensis showed higher nutritional requirement there. The A. cearensis seedlings showed moderate nutritional requirement for N and high for P. In Plinthic, their nutritional requirement for P was moderate and total N present in the soil was sufficient to meet growth demand in this stage. This small nutritional requirement for N may be associated with its ability to nodulation.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Pós-graduação em Geociências e Meio Ambiente - IGCE

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A introdução de espécies exóticas traz severas consequências para o ambiente, sendo a perda de diversidade a mais notável. Espécies exóticas podem competir por recursos com as espécies nativas, podendo assim causar a extinção de muitas espécies. A demografia e o padrão espacial de populações naturais também podem ser afetados pela presença de uma espécie invasora, o que pode levar a significativos efeitos para todo o ecossistema. Este trabalho teve por objetivo investigar o impacto causado na demografia e no padrão de distribuição espacial da palmeira Euterpe edulis pelo pisoteio e herbivoria do javaporco, resultado do cruzamento do Sus scrofa com o Sus scrofa domesticus. Esta palmeira tem especial importância para o ecossistema por ser considerada uma espécie-chave no ambiente, fornecendo alimento para muitas espécies. Foi feita uma parcela de 25 x 50m e contabilizados todos os indivíduos da palmeira presentes. Para avaliar a estrutura demográfica as plantas foram categorizadas em seis estádios de acordo com a altura: plântula, jovem I, jovem II, imaturo I, imaturo II e adulto. Para a distribuição espacial as plantas foram divididas em quatro estádios de acordo com o potencial impacto do javaporco e importância para o recrutamento: plântula, jovem, imaturo e adulto. Os dados foram coletados antes (2008) e depois (2014) da invasão do javaporco em um fragmento de mata estacional semidecídua no interior do Estado de São Paulo. A invasão do javaporco não afetou drasticamente a estrutura demográfica como um todo, mas houve uma redução considerável na proporção de plantas jovens I. Para avaliar os impactos na distribuição espacial usamos uma análise espacial de padrões de pontos univariada (entre plantas dentro de cada estádio) e bivariada (entre plantas de dois estádios). O javaporco não influenciou a distribuição espacial de plantas em cada estádio e nem as relações espaciais entre as plantas...

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Amphibian populations worldwide have been suffering declines generated by habitat degradation, loss, fragmentation and habitat split. With habitat loss and fragmentation in the landscape comes habitat split, which is the separation between the adult anuran habitat and breeding sites, forcing individuals to move through matrix during breeding seasons. Thus, habitat split increases the chance of extinction of amphibians with aquatic larval development and acts as a filter in the selection of species having great influence on species richness and community structure. The use of functional diversity allows us to consider the identity and characteristics of each species to understand the effects of fragmentation processes. The objective of this study was to estimate the effects of habitat split, as well as habitat loss in the landscape, on amphibians functional diversity (FD) and species richness (S). We selected 26 landscapes from a database with anuran surveys of Brazilian Atlantic Forest. For each landscape we calculated DF, S and landscape metrics at multiple scales. To calculate the DF we considered traits that influenced species use and persistence in the landscape. We refined maps of forest remnants and water bodies for metrics calculation. To relate DF and S (response variables) to landscape variables (explanatory variables), we used a model selection approach, fitting generalized linear models (GLMS) and making your selection with AICc. We compared the effect of model absence and models with habitat split, habitat amount and habitat connectivity effects, as well as their interaction. The most plausible models for S were the sum and interaction between habitat split in 7.5 km scale. For anurans with terrestrial development, habitat amount was the only plausible explanatory variable, in the 5 km scale. For anurans with aquatic larvae habitat amount in larger scales and the addition of habitat amount and habitat split were plausible...