Indications of changes in life history of fish as a result of hydroelectric power plants construction on the Dniester River

Environmental costs of hydroelectric power include the destruction of river habitats, transformation of river or land ecosystems into lake ecosystems, reduction of sediment passing downstream of dam, water acidification because of decomposing vegetation, blockage of fish migration routes, change in hydrological conditions downstream of the dam that cause numerous transformations within the ecosystem in general, and ichthyocenosis in particular. The main problem contributing to ecosystem change downstream is the unregulated release of cold water, or so called thermal pollution. This is one of the reasons provoking changes in life histories of fish, such as age of sexual maturity attainment, number of age groups and sex ratio in populations, individual fecundity, and existence of any shift in resource allocation either for growth or reproduction of fish populations situated downstream the cascade of the Dniester impoundments. The particular geo-political position of the Dneister River dictates that any possibility for a solution to the environmental problems must be in a transboundary context. In the present work, the existing experience of Integrated Water Management of Tranboundary waters is reviewed critically under the prism of Moldo-Ukrainian collaboration. Therefore, elaborated recommendations regarding mitigation of the negative environmental impacts of the hydropower plants on the Dniester River should be addressed equally to decision-makers in both countries.