Influence on the environment of the flood protection measures on the Dnister River near Sambir (Lviv region)

Abstract

The object of study is the environment within the territory of the dikes, sluices, pipe water passes, riverbank walls constructing and other hydrotechnical measures in the Upper Dnister valley and its left tributary Chukivka (Oreb) near Sambir. The aim of the study is the analysis of the possible expected impacts on the environment of constructing and exploitation of hydrotechnical buildings in Ralivka and Zadnistrya villages (southern Sambir suburb). The main methods of research are field investigation, mapping, photofixation, cartographical and statistical analyses. The input data are technical characteristics of the planed objects and measures, profile departmental information on the environmental components and ecosystems state. The information about the Dnister riverbed state, the character of the riverbed processes, erosion have been worked out. The resistance of different components of the environment against the planned measures and hydrotechnical building is analyzed. As the results of research, some recommendations and protective measures for minimization of negative ecological effects for floodplain and riverbed ecosystems have been substantiated. During the first year, the intensive sheet erosion is predicted and sediments runoff will increase during the intensive rain. Also, the local air temperature will increase. Temporary local climate changes can negatively impact on some biological species of the bank ecosystem. By degrees, the riverbank will be renewed in natural vegetation and local climate changes will become weaker. In the riverbed and floodplain, some reformation of the cross-sections and the riverbed relief forms will occur. So, the sediments balance in the Dnister and Chukivka riverbeds will be changed. In consequence of these processes, the sediments runoff will considerably increase in the Dnister downstream. The planed activity and described processes will not have considerable negative effects upon the flood plain and river valley biotopes. It is important for biodiversity and landscape diversity saving. Key words: flood protection, inundation, riverbed, floodplain, dikes, hydrotechnical engineering, regulating, Dnister River.