Metodologias para determinar vazão ecológica em rios

Abstract

The instream flows have the purpose to ensure the minimum conditions for maintenance of aquatic ecosystems. These flows have been called residual, remaining, ecological and environmental and are increasingly essential for sustainable management of water resources. Mostly methodologies to determine the instream flow were developed in the second half of the twentieth century and at the beginning of this century. This paper presents an analysis of methodologies used to determine instream flows in rivers. Besides describing the methods, this study is a summary table of each one, arranging them into four categories: hydrologic, hydraulic, habitat and holistic according to the approaches to their conceptions as well as the applicability and inconvenience of each one. Finally considerations about trends in the adoption of methodologies in Brazil and others countries are made and some opportunities, necessities of research for the improvement of existing methodologies as well as for the development of new and more appropriate methodologies for Brazilian rivers are presented.