Médio Vale do Paraíba do Sul: fragmentação e vulnerabilidade dos remanescentes da Mata Atlântica

• Autor(a) principal: Silva, Viviane Vidal da
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal Fluminense (RIUFF)
• Texto Completo: https://app.uff.br/riuff/handle/1/17161
• topic: Ciência ambiental; Meio ambiente; Desenvolvimento sustentável; Mata Atlântica; CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS

The habitat fragmentation, a process that reduces continuous areas to forest relicts, was evaluated in Barra do Piraí, Barra Mansa, Piraí, Pinheiral, Porto Real, Quatis e Volta Redonda districts, in the administrative area of the Médio Vale do Paraíba do Sul, Rio de Janeiro. In the study area, the different economic activities developed since the XIX century were based on the intensive exploration of land, industrial activities and urbanization, which have led to a new landscape pattern where the original Seasonal Semideciduous Forest was reduced to isolated fragments. The classification of the forest fragments, according to their secondary ecological successional stages, and the evaluation of the vulnerability regarding the anthropogenic pressure, were accomplished based on the size and form of the fragments, in a Geographic Information System. As a result of the Vegetation Cover Map, the fragments larger than 10 hectares were classified in size intervals. The Shape Index was adopted in the fragment shape analysis, and the Edge Density was used to evaluate the edge effects of fragments. The results have shown that the vegetation cover in the studied area is quite fragmented and the Intermediate Ecological Successional Stage prevails. Fragments with area higher than 100 hectares are expressive in the Seasonal Semideciduous Forest. However, the Atlantic Forest relicts that shown larger areas also present irregular border, and consequently are more susceptible to the external environmental effects. This fact is compensated by the fragment size that turns it less vulnerable to anthropic pressures. This research will contribute for the planning and the management of the remaining Atlantic Forest , as well as for the municipal public authority and for the private sector of the Médio Vale do Paraíba do Sul .