Дослідження екологічних аспектів при видобуванні донних відкладів з озерних екосистем Волині

The article summarizes fifteen years of scientific research on the impact of sediment extraction on the ecological state of Volyn lakes. The research results have shown that, according to detailed geological exploration, the balance reserves of sapropels in the Volyn region amount to 86 million tonnes of 60% moisture content, or about 95% of those explored in Ukraine. Most of them are concentrated in the Kovel and Kamen-Kashyr districts. A generalization of their ecological condition showed that the water depth in 20% of the surveyed lakes does not exceed one metre, and the depth of sediment layers ranges from 8.8 to 11.5 metres. For such lakes, eutrophication processes have become irreversible, and no preventive measures (introduction of herbivorous fish) will be able to restore their hydrological role. In such cases, technical reclamation of water bodies by excavating bottom sediments is the most effective and, in most cases, the only measure to restore their hydrological and recreational role [6, 20]. In addition to the reserves and quality indicators of sapropel, the research focused on the environmental aspects of bottom sediment excavation. The results of studies of the impact on the ecological state of lakes of two sapropel extraction technologies, hydromechanised and grabbing, on different types of their formation are analysed. When assessing the impact of sediment extraction on the ecological aspects of water bodies, the results were compared with the maximum permissible concentrations of ingredients, according to the requirements for the composition and properties of water of objects used for fisheries purposes.