ANNOTATION

to the dissertation of Tulegenov Erdaulet Askarbekovich on a topic "Ensuring the hydroecological safety of water bodies in the " for a degree of Doctor of Philosophy (PhD) in specialty «6D060800-Ecology»

Relevance. The Akmola region is the central region of the Republic of , which, due to the rapid development of the capital Nursultan and its suburbs, has increased its anthropogenic load. Water resources of the region undergo gradual degradation due to pollution, overuse, climate change. The tasks set in the dissertation work are in the interests of the State Program for Water Resources Management of the Republic of Kazakhstan for 2014-2040 ”dated September 13, 2013. In the Program, the problem of water security in conditions of limited and vulnerable water resources is considered as a threat to the national security of the state. The state program aims to ensure water security of the Republic of Kazakhstan by increasing the efficiency of water resources management, the preservation of water ecological systems. The object of the study is "11 lakes of the Akmola region". The subject of the study is environmental factors that pose a threat to water security for water bodies of the Akmola region. The aim of the thesis research is to develop a strategy for ensuring the hydroecological safety of water bodies in the Akmola region. The tasks of the research work: 1. Analysis of the anthropogenic load on water bodies of the Akmola region; 2. Hydrochemical studies of water bodies of the Akmola region for the presence of dangerous ecotoxicants; 3. Hydrobiological studies as an indicator of surface water quality; 4. Assessment of the reserves of water bodies for self-regulation and self- purification; 5. Preparation of a strategic plan to ensure the hydroecological safety of water bodies in the Akmola region. The novelty of the research work: - For the first time, a Strategic Plan for Hydroecological Safety for water bodies of the Akmola region was drawn up. - In contrast to the current strategic plans for water safety and water management in the Republic of Kazakhstan, the proposed strategy is a document primarily with environmental priority, and it also specifies how to achieve the goals set in Strategic Plan 2025 and the State Water Management Program of the Republic of Kazakhstan for 2014-2040 years. The scientific and practical significance of the research work. The scientific significance of the work lies in the collection and analysis of hydrochemical and hydrobiological indicators of lakes in the Akmola region for the period 2016-2018 and the assessment of the ecological status of these reservoirs. The practical significance of the thesis is determined by the fact that specific risks for the safety of water bodies are identified and, taking into account the obtained scientific facts, successive stages of a strategic plan are drawn up to preserve the ecological well-being of aquatic ecosystems. The provisions for the defense: 1. Based on the analysis of information on the intensity of technogenic impact on the territory of the Akmola region, as well as the impact of agriculture, namely the use of pesticides, were selected lakes with a threat to hydroecological safety. 2. The general hydrochemical indicators of water were analyzed and the indices of water pollution were calculated in the selected lakes of the Akmola region. 3. Analyzes were carried out on the content of 20 types of persistent organic pollutants in the bottom sediments of water bodies. A comparative analysis of their total share in all selected lakes is carried out. 4. The lakes were tested to determine the lethal toxicity of water on Daphnia magna, and non-toxic, medium lethal toxicity, and waters with high lethal toxicity were identified. 5. The indicators of primary daily productivity of phytoplankton were studied. Acute toxicity for Daphnia m. and low primary bio productivity are observed in reservoirs where the highest total content of persistent organic pollutants or an increased water pollution index are revealed. 6. The ecological well-being of water bodies was assessed by the index of the unsatisfactory state of herbivorous and predatory fish in lakes, and by the accumulation of heavy metals in them. 7. The saprobity of water bodies in the Akmola region by the species diversity of phytoplankton was studied. 8. An assessment is given of the self-cleaning ability of water bodies by the ratio of the amount of dissolved oxygen and the biological oxygen consumption in water. 9. A strategy for the safety of water bodies is proposed with the aim of reducing the toxic effects of sources of the spread of pollutants on water bodies. The structure and scope of the dissertation: The dissertation consists of an introduction, the main part, including a review of the literature, materials and methods, and the results of our own research, conclusion, list of used literature, including 175 sources of literature, applications. The work contains 115 pages of computer text, 14 figures, 22 tables. The content of the research work: The threat to water security for water bodies of the Akmola region is mainly represented by agricultural runoff from the outside. The greatest anthropogenic load is experienced by district (0.073 kg of pesticides per 1 ha of arable land), Zharkainsky district (0.039 kg / ha), Astrakhan district (0.024 kg / ha). The results of chemical analysis of the water of the studied lakes demonstrate a steady increase in the content of magnesium, nitrites, oil products, iron, and a significant excess in all studied months of surfactants, sulfates, and copper. According to the water pollution index, lakes Sultankeldy, Yesey, Kokai belong to class I (conditionally pure); to class II (slightly dirty) - Zhalauly, Itemgen, Lake without a name ( village), Zhalanash, Borovoye, Big Chebachye; to class III (contaminated) - Tastykol, Lake without a name (Astrakhan village). Persistent organic pollutants are present in the bottom sediments of the studied water bodies of the region, which so far do not exceed background levels according to sanitary standards. But by the total share of their content in the lakes, the following series of decreasing POPs can be made: 54% (DDT) > 12.71% (polychlorobiphenyl) > 12.59% (aldrin) > 7.85% (hexachlorobenzene) > 7.58% (chlordane) > 3.49% (endrin) > 1.51% (heptachlor) > 0.23% (dieldrin). Three types of lethal toxicity of Daphnia magna were found in the studied lakes: non-toxic waters (Lake without an name (Akkol settlement), Borovoe, Bolshoy Chebachye, Kokai, Esei, Sultankeldy), waters of lakes of moderate lethal toxicity (Itemgen, Untitled lake near Astrakhanka, Zhalanash), and waters with high lethal toxicity (Zhalauly, Tastykol). The highest values of daphnia death are caused by the combination of the presence of POPs and the general pollution of the reservoir: (Zhalauly, Tastykol). The highest values of the primary daily productivity of phytoplankton were observed in the Korgalzhin system of lakes, where the lowest toxicity of water was Sultankeldy (3370 ± 210 kcal / m2), Esei (2650 ± 380 kcal / m2) and Kokai (2170 ± 65.3 kcal / m2). Lakes with average productivity: Borovoe, Bolshoy Chebachye and Lake without a name (Akkol settlement): 1240 ± 298.4 kcal / m2, 987 ± 69.2 kcal / m2 and 428 ± 65.4 kcal / m2, respectively. Closer to the average productivity in this row are Zhalanash lakes (393 ± 45.8 kcal / m2), an untitled lake near the village. Astrakhan (284 ± 49.64 kcal / m2), Itemgen (362 ± 38.21 kcal / m2). The lowest bio-productivity was obtained in lakes where the water toxicity is higher: Zhalauly (122 ± 28.3 kcal / m2), Tastykol (96 ± 7.25 kcal / m2), which can be attributed to unproductive oligotrophic lakes. Fish do not live in the Tastykol and Zhalauly lakes, where the highest total content of persistent organic pollutants is revealed, the water pollution index, acute toxicity for daphnia and low primary bio productivity are increased. A study of the pathomorphology of fish in the Itemgen lakes, a lake without naming near the village of Astrakhan, Zhalanash showed an increased Index of unsatisfactory state of the environment (IUS). In lakes with high biological productivity and low WPI, Esei, Kokai, and Sultankeldy, the IUS is low. The saprobity index of the studied water bodies (S) ranges from 1.54 to 1.82, which corresponds to the β-mesasaprobic zone, which suggests that the lakes of the Akmola region are characterized by moderate water pollution. The ratio of the amount of dissolved oxygen (R) in water to BOD5 shows the fact that there are fewer lakes with a high potential for self-cleaning ability and a predominance of lakes with low self-cleaning ability, which poses a threat to the ecological well-being of these reservoirs. Our proposed water safety strategy is an ecosystem one and provides for the following key points: application of the principle of integrated water resources management; collecting information on the main indicators of the landscape; assessment of the accumulation of pollutants in water bodies; determination of the nature of waste in the catchment area, potential sources of ecotoxicants; assessment of the processes of self-cleaning of water bodies; selection of methods for the protection and rehabilitation of water bodies to maintain self-purification processes and improve water quality.