IWRA Proceedings

The damming can still be considered the main solution to fix the problems of water scarcity in semi-arid. However, the efficiency of this type of intervention is depends on the maintenance the quality of its waters. Marechal Dutra Reservoir - also known as Gargalheiras, with a capacity of about 40 million cubic meters, is used as a supply source of water for the cities of Currais Novos and Acari, in Rio Grande do Norte, and its regarded as the most eutrophic on the Piranhas-Acu watershed, resulting in severe restrictions to their multiple uses. The study purposed to examine the methods of environmental valuation derived from the production function as a potential tool to measure the impacts of eutrophication of the reservoir Gargalheiras, through the identification and valuation of main ecosystem services. Considering the nature of the environment, classified as an artificial ecosystem, which construction already involves several of important changes and impacts, the very question of identification of ecosystem services reveals some internal contradictions that resulted in restrictions on the approach. The analysis indicated that even with levels of degradation as evident and well documented, neither of the techniques proved to be able to capture the changes resulting from eutrophication. This paper points as the core of the problem the question of the anthropocentric character of Environmental Economics, current theoretical support of environmental valuation. As all analysis are held considering the measures of human welfare, and the human populations impacted by human degradation are relatively small, measures of economic impact also presented themselves as limited, disregarding important aspects of social and ecological order.

Palavras-chave: valoração; serviços ecossistêmicos; eutrofização