Condições para a manutenção da dinâmica sazonal de inundação, a conservação do ecossistema aquático e manutenção dos modos de vida dos povos da volta grande do Xingu.

Abstract

The aquatic biodiversity and the high fish productivity of the Amazon basin are mainly due to the annual dynamics of the flood pulses and the extensive wetlands. Some of the main impacts of the construction of dams for the generation of hydroelectricity are related to the changes in hydrological dynamics. The construction of the Belo Monte Hydroelectric Plant (HPP) interferes with the hydrological dynamics of the Volta Grande do Xingu (VGX) by diverting most of the flow out of that section of the river. Based on a critical review of the literature on the impacts of dams, as well as in direct field monitoring conducted by both the entrepreneur and our independent research, we found that water volumes substantially larger than those proposed by the company and the Brazilian National Agency of Waters (ANA) are necessary to avoid the loss of the connections between the river and its floodplains, which would result in negative cascade effects that would compromise food security throughout the VGX. The proposal to test the hydrogram established by the company for six years, with a drastic reduction of flow and loss of predictability and regularity of the annual flood pulse, violates the Precautionary Principle, runs counter to the accumulated ecological knowledge on the subject, and puts at risk the natural environment, its biota, and the ways of life of the human populations established in that region.