Salt composition of the waters of the Bureya reservoir

Significance. Significance of the work lies in the need to study the salt composition of the Bureya reservoir water from the beginning of filling, which is important for predicting the water quality of reservoirs in the Amur basin that are to be designed. The objective is to evaluate content of main ions in the water of the Bureya reservoir, and to identify factors determining their spatial and temporal variability. Methods. Hydro/chemical observations in the Bureya reservoir were made from 2003 to 2008 at five plots covering the major part of the water area. Water samples were taken from the surface, middle, and near-bottom horizons in winter, summer, and fall. Water samples were taken from the surface in January, July 2019 in the landslide area and in July 2020 at eight sites in the water body between the landslide and the hydropower dam. Analytical work was carried out according to the methods accepted in hydrochemistry. Materials of the Amur Basin Water Administration for 2005-2019 were used in the work. Results. The content of the main ions in the water of the reservoir during the filling period and the following years was assessed. The dominance of calcium ion among cations and hydrocarbonate ion among anions in the salt composition of water was shown. It is established that the emergence of oxygen deficit in water due to the increased area of flooded forests and reduced water inflow caused the absence of sulfate ion in the reservoir water in autumn and winter 2005. It is shown that staged filling of the reservoir contributed to gradual smoothing of differences in the content of major ions and stabilization of the salt composition of water in the sixth year of filling. In current conditions the content of sodium and potassium ions and chloride ions in the water area of the reservoir is relatively evenly distributed, the highest values of concentrations of calcium and magnesium hydrogen carbonates are observed near the mouth of the Tyrma River. The effect of a large landslide on the content of major ions in the water in 2019-2020 is considered.

Interdisciplinary Approaches to Assessing the Health of People Living in Environmentally Adverse Conditions

Background: The health status of the population of different ages was examined. Since children are very vulnerable to environmental factors, our goal was to examine their health status and compare them with those of the older population. Also one of the important tasks of our study was the installation of carcinogenic and non-carcinogenic risks for children and adults of different sexes. Methods: During our research, we calculated the air pollution index, investigated the incidence statistics of the population, and calculated the lifetime average daily dose (LADD). We investigated the content of sulfur dioxide, hydrogen sulfide, nitrogen oxide, ammonium and hydrogen carbonates and compared it with safe level of exposure. Results: In Aktobe, the Republic of Kazakhstan the external environment is polluted with boron and chromium, and in Aktau - with organic hydrocarbons. High morbidity rates in adolescents were found for endocrine disorders, digestive system diseases, and musculoskeletal system disorders. Estimating the prevalence and incidence of newly diagnosed diseases among women in Aktau showed that the overall incidence rate, as well as the incidence of respiratory and skin diseases, declines with age. The incidence of the genitourinary system and the number of nervous disorders increase, and the number of neoplasms increases in men population. A study of carcinogenic risks showed that children with Aktau, especially boys, have the greatest risk of cancer. Conclusion: The conducted research shows that environmental factors have a big impact on the health of the population.

PEAT-CONTAINING COMPOSITION CONTAINING MAGNESIA BINDER

Based on the new hydraulic magnesia binder, the compositions of the peat-containing composite material have been proposed and investigated. Hydraulic magnesia binder is an astringent composition of hydration-reaction hardening, which consists of an active caustic magnesia powder and a mixing fluid. As the fluid mixing an aqueous solution of magnesium bicarbonate Mg(HCO3)2 with a concentration of 13 g/l was used. Hardening forms water-insoluble products - magnesium hydroxide Mg(OH)2 and magnesium bicarbonates of general formula MgCO3·zMg(OH)2·nH2O, which makes it possible to harden and used products based on such a binder as in the air, and in water. The use of peat as a filler of the developed compositions will make it possible to obtain lightweight waterproof materials and products of heat-insulating purpose. It has been shown that the peat-and-magnesian compositions of all compositions have a hydration hardening coefficient of more than 1.0, which indicates intensification of the hydration and hardening processes in water conditions in comparison with air and large strength parameters. Using XRD the phase composition of peat products and peat- magnesium hardening compositions was established. Thermal analysis showed the presence of magnesium hydrogencarbonates in samples of compositions that are in the form of slightly crystallized neoplasms. Investigations by electron microscopy confirmed the presence of hydrocarbons such as magnesium particles dipingite Mg5(CO3)4(OH)2·5H2O and hydromagnesite Mg5(CO3)4(OH)2·4H2O in the form of thin plates with the vertical direction of crystallization. Increased water resistance of compositions based on hydraulic magnesia binder with non-water-resistant filler peat is due to mineralization of peat particles due to their impregnation with a solution of magnesium bicarbonate and the formation of water-soluble magnesium hydrogen carbonates in the loose porous structure of peat.

Statistic Functions of the Surface Water Bodies’ Water Quality Hydrochemical Indicators Distribution

Water quality chemical indicators functions’ distribution formation mechanism has been discussed. It has been demonstrated that the water quality indicators’distribution variability is characterized by considerable asymmetry and it cannot be approximated by normal distribution, excluding dissolved oxygen, hydrogen carbonates, and silicon. A pattern for water quality point indicators calculation construction on the basis of water bodies’ water quality regular hydro-chemical monitoring data has been proposed.

Effects of liming on the microbial biomass and its activities in soils long-term contaminated by toxic elements

The effects of liming by CaO and CaCO₃ on soil microbial characteristics were studied during laboratory incubation of long-term contaminated arable and grassland soils from the vicinity of lead smelter near Příbram (Czech Republic). The CaO treatment showed significant negative effects on soil microbial biomass C and its respiratory activity in both studied soils, despite the fact that microbial biomass C in the grassland soil increased sharply during the first day of incubation. The metabolic quotient (qCO₂) in soils amended by CaO showed greater values than the control from the second day of incubation, indicating a possible stress of soil microbial pool. The vulnerability of organic matter to CaO could be indicated by the availability of K₂SO₄-extractable carbon that increased sharply, particularly at the beginning of the experiment. The amendment of soils by CaCO₃moderately increased the soil microbial biomass. The respiratory activity and qCO₂ increased sharply during the first day of incubation, however it is not possible to ascribe them only to microbial activities, but also to CaCO₃ decomposition in hydrogen carbonates, water and CO₂. The pH values increased more sharply under CaO treatment in comparison to CaCO₃ treatment. The improvement of soil pH by CaCO₃ could be therefore more convenient for soil microbial communities.