MODELING THE IMPACT OF PLANNED HYDROELECTRIC POWER PLANTS ON ECOSYSTEMS

Abstract

Estimates of the impact of hydroelectric power plants (HPPs) on an ecosystem are exemplified by the HPPs construction planned in Mongolia in the transboundary Selenga river basin. Implementation of the HPPs projects can lead to essential changes in natural hydrological regime of the Selenga river basin in the Russian Federation, which will influence the regional ecosystems and economy. The international status of natural objects in Russia, which can be affected by these projects, is an important factor. First of all, this concerns Lake Baikal, the World natural heritage site. The paper contains the main results of this problem research. Based on an analysis of hydrological characteristics of Mongolian and Russian parts of the Selenga river basin, and plans for the development of water supply systems and hydro power in Mongolia, the regulated flow of the Selenga river was modeled for different possible operating conditions of HPPs and hydraulic structures (the projects of the Shuren HPP, the Egiin Gol HPP, and the Orkhon-Gobi water diversion system). Possible risks of the impact of potential Mongolian HPPs are revealed, first of all, the risks for the ecosystems of Russian part of the Selenga river. The impact is estimated for separate and joined projects (cumulative impact). The risks of the impact of the HPP construction and operation mean the probability that the values of hydrological, hydro-morphological, morphometric, physicochemical and other abiotic and biotic characteristics of ecosystems will go beyond the limits of natural variability.