Uso de fatores biológicos e ambientais na avaliação de níveis de vulnerabilidade de bosques do manguezal da Baía de Vitória, ES

• Autor(a) principal: Zamprogno, Gabriela Carvalho
• Data de Publicação: 2015
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/9161
• topic: Vulnerabilidade; Manguezal; Vegetação; Macrofauna; Propriedades do sedimento; Contaminantes; Baía de Vitória; Vulnerability; Mangrove; Vegetation; Sediment properties; Contaminants; Vitoria Bay; Ciências Ambientais; 55

The Vitória Bay is an estuary of great socio-economic importance in the state of Espirito Santo. Human interventions make this ecosystem more vulnerable to natural and anthropogenic stressors. An interdisciplinary analysis was performed to understand, through quantitative and qualitative methodology, the intrinsic characteristics that make a forest more or less sensitive to environmental changes in order to classify forests in levels of vulnerability. For this, it was examined vegetation, macrofauna, contaminants, sediment characteristics and urban pressure. Eight areas were established and in each area were demarcated two points, one for forest fringe and one for basin, totalizing sexteen sampling points. At each point were verified the vegetation structure data and semiannually samples were taken to verify particle size data and organic matter in the sediment, characterization of interstitial water, macrofauna and seedlings. In addition, at each point were evaluated the surface morphology of the sediment and sediment samples were collected for analysis of organic microcontaminants and trace and major elements. Although subject to various human impacts, the vegetation structure has forests with different degrees of maturity and structural heterogeneity, and the most distant areas of direct human impacts, inner portion of the Bay, have forests with higher levels of development and environmental quality compared to the ones closer to urban pressure points. Intermediary development levels were observed indicating pulses of environmental changes. The communities of epifauna of moluscs and crustaceans were different between the fringe and basin points, being influenced by flood frequency. Compositions of the communities were different between the points (1-8) and may have been influenced by anthropogenic changes, crustaceans were more diverse in points with greater anthropic pressure and molluscs, by contrast, showed a reduction in the values of ecological descriptors at those points. In relation to sediment contaminants, this study demonstrates that the points at the extremity of the Bay, subjected to greater human pressure, had higher concentrations of the compounds. Analysis of the sediment surface morphology along the Vitória Bay indicated that 63% of the points presented erosive trend. Indicators were determined to classify forests in three levels of vulnerability and showed to be good estimators in determining mangrove levels of vulnerability to future disturbances and can indicate priority areas for recovery and management.