Nowadays many aquatic ecosystems have become more eutrophic, as anthropic pollution causes the acceleration of eutrophication, which is a slow natural process. Therefore, the cultural eutrophication occurs more rapidly and causes problems in the affected water bodies. Since most of the reservoirs have complex use (flood attenuation, generation of hydroelectricity, household and industrial water supply, and irrigation), several models have been already developed to simulate the behavior of eutrophic ecosystems. The objective of this study was to determine the benefits of sustainable exploitation of an eutrophic lake. Therefore, the study aims, first, to analyze the trophic level in the lake, and second, to identify the best scenario of reservoir exploitation, in order to avoid the occurrence of eutrophic phenomenon or to minimize this effects. Also, based on the experimental data and an ecological model, the lake stratification and thermocline variation, correlated with operating conditions, have been studied.The study case is represented by a shallow reservoir in Romania, Golesti, which has 55 million m³ volume and a maximum depth of 32 m. Golesti reservoir allows flood control, hydropower generation, water supply (household and industrial), and irrigation. Values of inflow and outflow from January 2008 to October 2009 were available for the studied reservoir.
reservoir, eutrophication, ecological model, nutrients, water quality
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