Shipka M. Geoecological state of the Poltva river basin and its optimization

The thesis for the degree of Candidate of Geographical Sciences (Ph.D), specialty 11.00.11 ‒ constructive geography and rational use of natural resources. ‒ Lesya Ukrainka Volyn National University, Lutsk, 2021. The thesis is dedicated to the study of the geoecological state of the Poltva river basin system, the analysis of factors of its formation, and the identification of the ways of its optimization. A systematic approach (its both geographical and ecological aspects) to study the quality of the environmental components is implemented. The object of the complex geoecological research is the river basin as an integral establishment with a hierarchical structure. The analysis of natural conditions and anthropogenic factors of the formation of the geoecological state of the Poltva river basin is conducted. It is determined that the level of settlement adaptation within the watersheds and the associated water management complex has a significant impact on the water quality of the rivers. Lviv city location at the upper part of the Poltva river basin is a determining factor in the formation of the river water quality. The spatio-temporal dynamics of the settlement load of the research area and the population density within the catchments are analyzed. The water management complex includes the sewerage system of Lviv city, two large groundwater intakes for the city water supply, sewerage systems of communal and industrial enterprises of villages, and 10 reclamation drainage systems. According to the results of the analysis of the State Ecological Inspectorate, the impact of the closed landfill for the solid household waste of the Lviv Municipal Enterprise «Zbyranka» and the barns with sour goudron on the quality of environmental components is determined. The structural organization of the river network of the Poltva basin and its transformation are studied implementing large-scale multi-time topographic maps and conducting field studies. The visual decipherment of the space images is carried out and a map of the land use structure of the river basin is marked. It is determined that relief and soil cover of the study area have a decisive influence on land use. The level of anthropogenic load on the Poltva river basin is estimated according to integrated indicators and as a result the studied territory was zoned by the degree of anthropogenic transformation of lands. The level of land resistance to degradation processes is analyzed by overlaying the soil map, the land use structure map, and the slope map. The results of the analysis of the State Ecological Inspectorate and literary sources are processed for the determination of the contamination of soils within the Poltva river basin. The investigations of the geoecological state of vegetation included the analysis of the land use structure map, the study of the spatio-temporal dynamics of forest cover by processing multi-time topographic maps, and the degree of forest damage in the research area by pests and diseases. The research resulted in the identification of major environmental problems of the Poltva river basin and the determination of the ways to solve them. Since the priority environmental problem is significant pollution of the Poltva river, the planned modernization projects at the treatment facilities of Lviv city are considered. Measures aimed at reducing the impact of polluting enterprise pollution on the environment are proposed. Features of the implementation of the new water management system by the EU Water Framework Directive are studied. The map of the land use optimization of coastal areas and the map of the water protection zone of the Poltva river is developed. The improvement of the waste management system within the Poltva river basin involves the implementation of the project of reclamation of the solid household waste landfill of the Lviv Municipal Enterprise «Zbyranka» and the application of measures aimed at reducing the clogging of the study area. The map of optimization of the land use structure in the Poltva river basin, which includes agrotechnical and phytomeliorative measures, is developed. The measures to optimize the forest use are recommended. The degree of the representativeness of natural complexes in the land use structure of the nature reserve fund is analyzed and the prospects for the creation of new protected areas within the Poltva river basin are studied. Key words: river basin, land use, anthropogenic load, the quality of water, optimization.