Avaliação dos efeitos da construção das usinas hidrelétricas sobre a riqueza vegetal relacionada à perda das matas ripárias noTocantins

Abstract

Riparian vegetation plays a very important role in protecting natural resources and conserving biodiversity. However, the area occupied by this vegetation has diminished over the last decades due to the anthropic actions, disregarding its relevance. This study evaluates the potential loss of vegetation diversity of riparian zones with the construction of large hydroelectric projects in cascade in the cerrado biome from the analysis of information obtained in studies of floristic survey and monitoring of four large hydroelectric dams built in the Tocantins river basin. The research was carried out from the licensing studies of four hydroelectric power plants (São Salvador, Peixe Angical, Lajeado and Estreito) built along the Tocantins River, in the Tocantins basin. The data collection was done in official documents (Studies and Environmental Impact Report of the Hydroelectric Power Plants) obtained in the institutions that acted in the licensing. The analyzes were performed based on the frequency of occurrence of species and families in each HPU, applying percentage calculations and Jaccard Similarity Index. Considering the results obtained, the present study suggests that the construction of the studied UHEs generated great negative effects on the plant diversity of the cerrado around the Tocantins basin, with the need to deepen the environmental impact studies and develop viable strategic plans for reduction of