Chemical Composition Of Water Research Articles

Variability of hydrochemical parameters of small boreal lakes under natural and anthropogenic factors (case study of NW Russia)

Small lakes of the boreal zone are highly sensitive indicators of both global environmental change and local anthropogenic pressure. This work presents the results of multidisciplinary study of three small, seasonally stratified lakes of NW Russia, conducted since 2002 to the present time. These lakes were subjected to various degree of impact by rural population and agricultural activity since the beginning of twentieth century but the population and anthropogenic pressure have decreased since 1990s. To monitor the recovering of these lakes from human impact and to relate the evolution of their hydrochemical parameters to short-term weather events and global climatic trend, we measured the lake water temperature and chemical composition (carbon, macro- and micronutrients, trace elements) in summer and winter over full depth of the water column. The pH and concentration of DIC, SO4 and H2S decreased over past decade. Concentrations of Si and nitrite increased over past 15 years, probably linked to progressive replacement of diatoms by cyanobacteria. We also recorded an increase in concentration of Cl and major cations in all lakes, likely linked to increasing connection to groundwater reservoirs. Some trace elements (Fe, Mn, Al, Zn, As, Pb) can serve as suitable indicators of on-going natural processes controlling lake response to external factors. Unlike widely reported global trend of DOC and Fe concentration increase in boreal surface waters of Europe and Northern America, such trend was not discernable in studied Fe-rich humic lakes. We conclude on the necessity of complex, multidisciplinary studies of small humic lakes in the boreal zone, because these “model” lakes can serve as important proxies of on-going environmental changes in highly abundant aquatic ecosystems of poorly characterized regions of NW Russia.

Physico-mechanical behaviour of Oil Palm Broom Fibres (OPBF) as eco-friendly building material

Until recently, the rib of the leaflets of the oil palm tree was only used for making brooms due to its stiffness and durability. However, the mechanical properties of this fibre are unknown. Due to the geometrical variation of the cross-section of the fibres along their length, this study divided them into 4-categories. The result of this study reveals that the fibres have a specific gravity between 0.45-0.84 and diameter varying between 0.20 mm (at the tail) and 4.00 mm (at the cap). Maximum tensile strength of 900 MPa was recorded. Scanning electron microscopy of fibre cross-sections revealed graded cavities concentrated at the core but a densely packed cortex. This radial and longitudinal density gradient is responsible for the phenomenon whereby the fibres are stiffer in bending but possess reduced tensile strength towards the cap. Further investigations carried out on the fibres include water absorption, chemical composition and thermogravimetric analysis. The fibre is proposed for use as natural-fibre reinforcement in cement and polymeric composites as it is cheap, and void of high carbon footprints associated with the use of conventional reinforcement materials in construction.

Natural and Anthropogenic Conditions of the Chemical Composition of Pit Lake Waters (Based on Example Pit Lakes from Central Europe)

The article presents a classification of hydrochemical types of waters in pit lakes. Although natural factors significantly influence the chemical composition of water, the differences between hydrochemical types are also determined by anthropogenic factors. The chemical composition of the water in pit lakes is primarily determined by the kind of rocks mined during the excavation, while secondary anthropogenic impacts can modify the chemical composition of the water. A multidimensional clustering analysis of the water was performed, which allowed three main types of hydrochemical reservoirs to be delimited for the pit lakes assessed in this study: a bicarbonate–magnesium–calcium water type (HCO3–Mg–Ca), a bicarbonate–calcium water type (HCO3–Ca), and a sulphate–calcium water type (SO4–Ca).

Influence of historical landscape on aquatic plant diversity

AbstractQuestionsThe historical composition of landscapes is recognized as an important factor for explaining plant diversity, because species assemblages are not only patterned by current ecological conditions, but also represent legacies of the past. Contrary to terrestrial ecosystems, the influence of history has rarely been considered for aquatic communities. Here, we examined the effect of past land use on aquatic plant communities of freshwater shallow lakes. We first aimed to identify the relevant scale for studying landscape effects on macrophyte communities and then to test the relative influence of environmental variables and past and recent land use on aquatic plant assemblages.LocationAtlantic coastline, southwestern France.MethodsWe surveyed shoreline macrophyte communities of 17 lakes and used species accumulation curves to estimate taxonomic richness. We used water chemistry and lakes’ morphological features as environmental variables and reconstructed land‐use occupancies of lakes’ watershed with aerial pictures of 1945, 1965, 1985 (past) and 2002 (recent). We examined landscape change with principal component analysis and taxonomic composition with non‐metrical multidimensional scaling. We then evaluated the relative influence of morphological, chemical, past and recent land‐use factors on taxonomic richness and composition with variation partitioning methods.ResultsWe found that the studied landscapes exhibit a trend toward an increase of urban and arable fields areas at the expense of semi‐natural ones. Water chemical composition and past land use of the whole watershed (particularly urban and semi‐urban areas) were strongly inter‐correlated, and explained the major part of the variation of taxonomic richness and composition.ConclusionsThese results underline the importance of historical factors in explaining aquatic plant diversity and suggest delayed responses of communities to anthropogenic pressures. Integrating historical factors in future analyses of aquatic ecosystems would thus greatly contribute to understanding ecological processes, and is crucial for the conservation and management of macrophyte communities.

ГЕОХІМІЧНА ХАРАКТЕРИСТИКА РІЧКОВИХ ТА ҐРУНТОВИХ ВОД (Зовнішня зона Передкарпатського прогину)

Geochemical peculiarities of river and groundwaters of the Outer zone of the Precarpathian deep have been established. It is revealed that the main feature of the distribution of salt composition indicators in the Dniester River and its influxes is hydrochemical zonality, which does not depend on the flow direction of the rivers, but is consistent with the physics-geographical and geological features of the area to which the man-made factor is imposed. There is an increase in concentrations of sulfate, calcium in the left bank confluent of the river Shchyrka. The waters from the Tysmenytsya, Kolodnitsa and Dniester rivers in the village Kolodrubi are characterized by the highest amounts of sodium and chlorides and are sodium chloride-hydrocarbonate composition. The water composition of the Dniester River (Rozvadiv village), its confluents Bystrytsia and Letnyanka are hydrocarbonate calcium (sodium-magnesium-calcium), Shchyrka, Vereshchitsa – sulfate-hydrocarbonate calcium (magnesium-calcium). The index of biochemical oxygen consumption for 5 days in the waters of Tysmenytsya River reached 4.5 mg O2/dm3, while in other rivers it was 0.70‒3.20 mg O2/dm3. The content of O2 soluble in the waters of the river Vereshchytsya was 0.29 mg/dm3, the value of biochemical oxygen consumption was 11.4 mg O2/dm3. In the chemical composition of river waters, there is an increase in the concentrations of sodium, potassium and chloride ions from the left bank to the right bank confluents of the Dniester. In the left-bank confluents, in the chemical composition of water dominate the contents of calcium and hydrocarbons ions. The heterogeneity of the lithological composition, the instability of the thickness of the aquifer both in the horizontal and vertical directions, and the different technogenic influence form the irregularity of pollution and its local distribution in groundwater.

Characteristics and influencing factors of hydrochemistry and dissolved organic matter in typical karst water system.

The unique hydrogeological conditions of karst area make the groundwater react rapidly to rainfall events, which makes the groundwater more susceptible to anthropogenic pollutions. The current study based on a combined excitation-emission matrix fluorescence spectroscopy and parallel factor analysis (EEM-PARAFAC) and geochemical-statistical investigation of water samples from the karst water system in Xintian County, Hunan Province, China, gives crucial information about the principal factors influencing karst water hydrochemistry and dissolved organic matter (DOM). The analyzed data revealed that both surface water and descending spring samples were within the Ca-Mg-HCO3 water type and dominated by humic-like fluorophore, and well water samples were within both the Ca-Mg-HCO3 and Na-HCO3 water types and controlled by protein-like fluorophore. The chemical compositions of surface water and descending springs were mainly influenced by the weathering of silicate, carbonate, and evaporate rocks and precipitation. In addition to be affected by the weathering of silicate, carbonate, and evaporate rocks and precipitation, the well water was also impacted by ion exchange and other activities like anthropogenic. The DOM in the karst water system was affected by allochthonous and autochthonous inputs as well as the chemical compositions of the water.

Assessment of the Open Water State in Water Use Point of the Population the Murmansk Region

The study of the ecological situation in lake basins, including the assessment of water pollution, has become relevant recently, since the quality of drinking water depends on the quality of surface water bodies. The paper reflects the main results of water quality assessment of Lower Vaengskoye Lake in the Murmansk Region in the period 2016–2017. Hydro-chemical studies included the following indicators: biochemical consumption of oxygen, mass content of ammonium, nitrites, nitrates, sulfates, iron, coloration and hardness of water, permanganate oxidation. Natural factors are decisive contributors to the chemical composition of water. The sanitary status of the lake was assessed using the methods of microbiological analysis of water from the surface sources of water use. According to the microbiological indicators in the studies, water meets the requirements of hygienic standards. According to sanitary-chemical indicators, there is a variance with the requirements of hygienic standards in 10% of all the studies conducted, namely in terms of coloration, permanganate oxidation, and iron. On the whole, the quality of the lake’s water during the period of the study was assessed by the value of the integral hydro-chemical index as “pure” water (by the value of WPI). The results of the tests make it possible to conclude that the degree of the anthropogenic burden on the reservoir studied is insignificant.

Regional-scale investigation of dissolved organic matter and lead binding in a large impacted lake with a focus on environmental risk assessment

Environmental risk assessment (ERA) increasingly relies on speciation modeling of bioavailability. Heavy metals are the most prevalent pollutants globally, and dissolved organic matter (DOM) plays an important role in speciation and bioavailability of heavy metals. Due to the variation of DOM properties in natural aquatic systems, improvements to the standard one-size-fits-all approach to modeling metal-DOM interactions are needed for ERA. In this study, we investigate variations in DOM and lead (Pb)-DOM binding in Lake Tai (Taihu), a large, impacted lake in eastern China that is characterized by a complex drainage network and is an important water resource at a regional level, and we assess implications of our findings within the context of ERA needs. In our study, DOM in water samples collected from across the 2,400 km2 area of Taihu was characterized using three-dimensional excitation-emission matrix and synchronous fluorescence spectroscopy spectra, the latter being used to calculate conditional stability constants for metal binding. Parallel factor analysis and peak picking were used to assess contributions of protein- and humic-like components of DOM, and fluorescence indices indicative of diagenetic processes were calculated. These quantities calculated from spectroscopic studies, in addition to water quality parameters, were analyzed by bivariate and multivariate analysis. Results show that different DOM components are highly variable across different regions of Taihu, and bivariate and multivariate analyses confirm that water quality and DOM characterization parameters are strongly interrelated. This reflects the different inputs, diagenetic and transport processes across the large expanse of Taihu. We find that the conditional stability constant of Pb-DOM binding is strongly affected by the water chemical properties and composition of DOM, though the conditional stability constant is not itself a parameter that differentiates lake water properties in different regions of the lake. The variability of DOM composition and Pb-DOM binding strength across Taihu is consistent with prior findings that a one-size-fits-all approach to metal-DOM binding may lead to inaccuracies in commonly used speciation models, and therefore such generalized approaches need improvement for regional-level ERA in complex watersheds. The approach taken here to obtain site-specific metal-DOM conditional stability constants for use in increasing the accuracy of speciation modeling is fit-for-purpose for ERA applications at regional levels because the approach is relatively simple, inexpensive, and amenable to high throughput analysis.

Hydrochemical and Isotopic Characteristics of the Lake Balkhash Catchment, Kazakhstan

Lake Balkhash is one of the largest lakes in the world. It is located in arid Central Asia and receives major water from the Ili River, which is an international river flowing across China and Kazakhstan. Hydrochemical and isotopic measurements of waters can provide an improved understanding of hydrogeochemical processes and environmental characteristics, which is useful for water resource management in arid regions. In this study, δD, δ18 O, and major ions in water samples from the Lake Balkhash catchment were analyzed using an integration of mathematical statistics, Piper diagrams, Gibbs model, and principal component analysis (PCA). Water types and main mechanisms controlling the hydrochemistry presented a clear spatial heterogeneity. The chemical composition of lake waters was dominated by SO4-Na and Cl-Na type, whereas river waters were classified as a HCO3-Ca type. The chemical composition downstream of the Ili River evolved from HCO3-Ca to SO4-Na-Cl type. Gibbs model suggested that the main mechanisms controlling the lake water chemistry were evaporation-crystallization processes, and that major ions in the river water were affected by rock-weathering and evaporation processes. The main controlling factors of the water chemistry changed from the upstream to the downstream, and may have related to spatial differences whereby the upstream area experienced higher rainfall and snow melt, and the downstream area experienced relatively higher evaporation. PCA analysis showed that human activities also played an important role in the chemical composition of water sampled from the lake, middle and lower reaches of the Ili River, and other rivers. The isotopic compositions of the lake and river waters varied spatially. In the lake waters, positive isotopic ratios and negative deuterium-excess values indicated that evaporitic enrichment dominated the changes in the isotopic signature of the lake water. In river waters, isotope values located near the global meteoric water line (GMWL) and lower slopes of the regression lines (r=0.91, P<0.001 for Ili River, and r=0.63, P<0.001 for other rivers), were associated with a stronger influence of rainfall and weaker evaporation. Correlation analysis showed that there were significant relationships between isotope values and chemical parameters in the lake water, especially in the eastern area, thus suggesting that extensive evaporation led to simultaneous enrichment of isotopes and ions in the lake water.

Assessment of heavy metal contamination in natural waters of Dereli, Giresun: an area containing mineral deposits in northeastern Turkey.

The concentration of heavy metals in the natural waters of the area surrounding Dereli (Giresun), a mineralized area, was determined. In addition, the physicochemical parameters (such as pH, Eh, and HCO3-) influencing the concentration of dissolved metals in waters were evaluated. Samples were collected from stream, spring, and main river waters, some of which are used by local residents for drinking, fish farming, and animal husbandry. The present data indicate that the water-rock interaction is the main process controlling the chemical composition of waters in the area. The waters are predominantly CaMgHCO3-type waters with alkaline pH values. Heavy metal concentrations (Pb, Zn, Cu, Fe, Mn, U, Cd, As, Hg, Sb, Ni, Co, and Ba) in waters were generally low. Relatively high values of certain metals were determined in waters of the Kotana and Kurtulmus sites of Dereli. The levels of Pb in the river, stream, and spring water samples in these sites were somewhat higher than the Pb values reported in the literature for natural waters. However, these values only slightly exceeded the Pb water limit values proposed by the USEPA and the WHO. In addition, the concentrations of other heavy metals, except Pb, were fairly similar to those of other natural waters and these values were also under the drinking water limits set by the WHO and the USEPA. This study shows that waters in the area of Dereli were not significantly affected by mineralization. This is most likely caused by the bicarbonate-rich waters affecting the dissolved metal concentrations.

ИССЛЕДОВАНИЕ ТРАНСФОРМАЦИИ ХИМИЧЕСКОГО СОСТАВА ПОВЕРХНОСТНЫХ ВОД С ИСПОЛЬЗОВАНИЕМ МОДЕРНИЗИРОВАННОЙ КЛАССИФИКАЦИИ АЛЕКИНА

Climatic changes and value of anthropogenic load of watershed of the rivers can be main reasons. The article researched long-term changes in the chemical composition of rivers in Ukraine. Long-term changes in the chemical composition of the river waters of Ukraine were analyzed using the modernized Alekin classification (modernization was proposed by V.K. Khilchevskyi and S.M. Kurylo). The additions introduced by the authors to the basic classification of O.A.Alekin allow fixing the dynamics of changes in the chemical composition of natural waters by cations at the group level, as well as at a more detailed level, revealing quantitative changes in the relative content of class-forming anions (at the level of subtypes). Taking it into account for the most relevant tasks which arise for hydrologists and hydrochemicals are considered to be determination of modern regularities of streamflow and hydrochemical regime in conditions of warming which happens and assessments of such changes for the perspective. The mineralization of water and concentration of the main ions in river waters change for many reasons. Studying has been executed on the Udaj river, Tur`ya river, Sula river. The trend of increasing salinity of river water is detection. Main changes are taking place in the spring. During period of supervisions there was growth of mineralization of water: Sula – from 440 to 1125 mg/dm3.The main factor there is an increased part of groundwater flow. In favor of this conclusion the following results of researches serve. The special executed calculations showed dependence between part of ground flow and chemical composition of water of the rivers. Different classifications are used to systematize natural waters by chemical composition. Attempts to classify water in accordance with the general conditions by which their chemical composition is formed are known. For analysis of long-term changes of the hydrochemical regime in different phases of the water was found and application of the classification of Alekin (modernizated). Modernization does not touch the highest trait – class, but concerns groups and types, with the introduction of a new taxon – subtype. Modernization to the basic classification of Alekhin allow to fixed in detail the dynamics of changes in the chemical composition of natural waters by cations at the group level. At a detailed level, quantitative changes in the relative content of anions (at the level of proposed subtypes) can be fixed. Verification of the modernized classification of O.A. Alekhin, made on 25 rivers of the Dnipro river basin. Rivers are located in different environmental zones, have different anthropogenic pressure and term of observations (40 – 60 years). An attempt was made to apply the modernized classification to other types of natural waters – groundwater and atmospheric.

Comprehensive monitoring of the Klyazma reservoir

The research was carried out during the comprehensive monitoring of the Klyazma reservoir in 2019. The work is devoted to the assessment of long-term environmental changes under the influence of natural and anthropogenic factors. The research combines two traditional methods of analysis. A layer-by-layer study of diatomic complexes and chemical composition in the bottom sediments of the reservoir was carried out. The results obtained were compared with the results of comprehensive monitoring on the taxonomic composition of phytoplankton and the chemical composition of water in the reservoir's water area. The results of previous studies on the chemical composition of water in the reservoir were used. In addition to the traditional forms of chemical and hydrobiological analysis, an innovative method of graphical analysis was applied to phytoplankton complexes and the principle of unification of bioindication methods was applied for diatom complexes from sediment columns. The main scenarios of taxonomic proportions transformations in phytoplankton and diatom complexes were determined using the method of graphical analysis for the Klyazma reservoir water area. The transformations are caused by the influence of water from the Moscow channel and the planned annual lowering of the water level in the reservoir. Bottom sediments showed a regular increase in the reservoirs level of saprobisation. Presumably, this is due to a non-linear increase in the number of tourists and an cahnges in recreational load. Pronounced accumulation of Cu, Zn and other heavy metals in the coastal zone of the reservoir was confirmed.

Assessment of the post-pyrogenic water toxicity in the north-eastern part of the Great Vasyugan Mire (Western Siberia)

This paper devoted the analysis of the post-pyrogenic water toxicity in the north-eastern part of the Great Vasyugan Mire with a test culture of Daphnia magna Straus. It was found that the water samples of pine-shrub sphagnum bogs have a negative impact on the test organisms D. magna Str. The most toxic effect on test organisms provided by pH value. The chemical composition of waters is determined by the high content of NH+4, Fetotal, organic matter at all points of the study. The MPC exceeded for NH+4, Fetotal and COD. The studied post-pyrogenic areas are characterised by an increase in the concentration of heavy metals (Zn, Pb) and Fetotal in waters.

Assessment of the relationships between elements and organic matter in water after a large landslide in the Bureyskoye reservoir (Russia)

The article provides information on statistical approaches to identify the dominant factors that influenced the water quality in the Bureyskoye reservoir after a large landslide in December 2018 blocked access to a hydroelectric power plant. To restore the hydrological regime, blasting operations were carried out using trinitrotoluene and hexogen. The main indicators of water quality were volatile organic matters and elemental composition that varied along different banks above and below the landslide body and under the influence of explosives. In water samples from the artificial canal after the restoration of the reservoir flow, the content of Fe, Mn, Al, Cu and Zn remained at a low level and did not reach the initial values established prior to the blasting operations. However, an increase in the content of Pb by 7 times and Hg by 80 times was noted. The presence of methanol and methylated benzene derivatives in water could stimulate the formation of more toxic methylmercury, posing a risk to aquatic organisms. Correlation analysis was used to process the obtained data which made it possible to differentiate the contributions of natural (landslide, river tsunami) and anthropogenic factors (blasting) to the change in the chemical composition of water in the reservoir.

«МОНІТОРИНГ ПРИРОДНИХ ВОДНИХ ДЖЕРЕЛ КАРПАТСЬКОГО НАЦІОНАЛЬНОГО ПРИРОДНОГО ПАРКУ» (2019) – ПЕРША В УКРАЇНІ МОНОГРАФІЯ ПРО ДЖЕРЕЛА

The monograph “Monitoring of springs of the Carpathian National Natural Park” is presented and analyzed in the article (authors R.L. Kravchynskyi, V.K. Khilchevskyi, M.V. Korchemlyuk, O. M. Stefurak / Ed. by V.K. Khilchevskyi), published in 2019. This is the first such monographic study of of springs in Ukraine. It presents the results of monitoring studies of natural of springs in the territory of the Carpathian National Natural Park (field surveys, studies of the hydrological regime, chemical composition of water). Inventory and accounting of springs is included in the plan of annual nature conservation activities held in the park. There are all the necessary conditions for a comprehensive study of natural groundwater output to the surface – scientific, logistical and informational base. In 2019, after the grant of two wetlands in the Carpathian National Park (Prut and Pogorelets) international status and their inclusion in the list of wetlands protected by the Ramsar Convention on Wetlands of International Imports of International Imports especially as Waterfowl Habitat, 1971 – the study of environmental components, including springs, becomes more relevant and practical. About 40 expeditions were conducted to investigate springs in three major natural complexes in the Carpathian National Nature Park: Skibov Gorgany, Yasin-Verkhovyna Inter-Mountain Basin, and the Chernogorsky Massif. In the hydrological aspect, these are the basins of the Prut River. About 300 objects were covered by the monitoring studies. As a result of the analysis of literary sources, summarization of the information obtained in the expeditions, laboratory conditions and during the camera processing of materials, a considerable amount of data has been formed for writing the first monographic study in Ukraine on this subject, structurally consisting of eight sections. The methods used in the study of of springs and interpretation of data are presented. The book notes that in our time the multifaceted structure of the ecological and functional significance of natural of springs can be the subject of interdisciplinary research, including natural, technical, economic, often medical, and sometimes humanities. The necessity of increasing attention to the monitoring of natural of springs from environmental experts – geographers, hydrogeologists, hydrologists, ecologists, is justified.

ПРОБЛЕМЫ ИСПОЛЬЗОВАНИЯ ИСТОЧНИКОВ НЕЦЕНТРАЛИЗОВАННОГО ВОДОСНАБЖЕНИЯ НА ТЕРРИТОРИИ ЮГА ТОМСКОЙ ОБЛАСТИ

Introduction. Sources of non-centralized water supply are the most important resource of drinking water for the population of rural areas. As a rule, water is taken from small depths, which makes it vulnerable to pollution. This type of water use is characterized by the absence of any preliminary water treatment. The constant use of groundwater for drinking can negatively affect the health of the local population since the indicators of its chemical and microbiological composition are not controlled in any way and do not always meet the quality standards. All this determines the relevance of the research conducted in the territory of the Tomsk District (Tomsk Region). Methods. Groundwater quality was assessed by comparing the concentrations of substances in the studied water samples with the background values established for the given territory in relation to Sanitary Norms and Regulations as well as microbiological indicators. Changes in the chemical and microbiological composition of the studied water, caused by economic activity, were taken as “pollution” as compared to the natural (background) state for this territory as well as sanitary and hygienic standards. Results. According to the results of studying the chemical composition of water, high levels of the following components were observed: total hardness, Na+, K+, SO42–, Cl–, NO3–, Fe, and Mn. As for NO3–, Fe, and Mn, their concentrations exceed manifold not only the background values but also the maximum allowable concentrations for drinking water. Microbiological analysis showed a large number of microorganisms from various physiological groups, which indicates a high degree of bacterial contamination of water. We present possible reasons for the input of pollutants into the water and review briefly the adverse health effects. Conclusion. In order to prevent the possible negative impact of excessive contents of various components in the chemical composition of water on the health of the local population, preliminary water treatment using available methods is recommended.

Distribution of nutrient elements and organic carbon in the lower reaches of the Selenga River

The content of nutrient elements and organic carbon in the water of the lower course of the Selenga River and its long-term changes under the influence of natural and anthropogenic factors are considered. For analysis, data from field studies carried out in the summer of 2018 and 2019 was used, as well as long-term materials on the chemical composition of water in the closing section of the river (Kabansk gauging station). Today, the hydroclimatic factor largely determines the chemical composition of water in the lower reaches of the Selenga. The aridization of the climate in the region and the associated decrease in the water content of the river led to a decrease in the dilution of diffuse and point pollution. During the period from 1980 to 2017, the average long-term concentrations of total phosphorus increased by 2 times and nitrates by 2.25 times. At the same time, the supply of silicon to Lake Baikal decreased by 1.7 times. Its concentration determines the growth of diatomaceous algae - the main producer of organic matter. Climatic changes largely influence to the transformation of land use on the watershed of the lower reaches of the Selenga River. It was found that agricultural activity on the watershed increases the proportion of suspended form of chemical elements (in particular phosphorus and organic carbon). In the delta of the river, when hydrodynamic conditions change, suspension deposition is observed, the content of dissolved forms of nutrients and organic substances increases. In heated delta areas with low flow rates and intensification of production processes, the organic form of phosphorus prevails over mineral.

Ecology of estuarine waters in small rivers of Southern Baikal in 2018

We conducted comprehensive studies in small rivers and estuarine water areas of Southern Baikal during the under-ice (March) and summer (July) periods of 2018. The chemical composition of water, the number of microorganisms, their diversity and metabolic potential in the studied areas correlated with the geographic location of the rivers, their flow and the degree of anthropogenic impact.

ЕКОЛОГІЧНА ХАРАКТЕРИСТИКА Р. ПІВДЕННИЙ БУГ ТА ОЛЕКСАНДРІВСЬКОГО ВОДОСХОВИЩА ЗА ГІДРОХІМІЧНИМИ ПОКАЗНИКАМИ

The paper presents the results of researches of the modern ecological state South Bug and Aleksandrovskogo of storage pool the affected of the South Ukrainian power complex zone on hydrochemical indexes (main ions, mineralization of water, biogenic matters), which are the indicators of the ecological state of natural reservoirs. Research of the hydrochemical mode South Bug and Aleksandrovskogo of storage pool within the limits of the South Ukrainian power complex conducted during 2019. An analysis of the got data is as compared to those, which took place more early, rotined that the water masses South Bug tested substantial changes (on the indexes of the chemical state). The conducted researches rotined that chemical composition of water S.Bug and Aleksandrovskogo of storage pool had been characterized sufficiently by the high values of mineralization of water, maintenance of main ions, especially sulfate and to general inflexibility.The features of spatio-temporal changeability of the main hydrochemical indicators of quality of water environment are set. Tendency of gradual increase of maintenance of main ions and of mineralization of water is traced on the longitudinal type of the river. The gradual diminishing from the winter to the summer and increase of mineralization of water and main ions an autumn is traced in a seasonal aspect. It is known that the important index of the sanitary-hygenic state of natural reservoirs is content of biogenic matters. Worsening of the ecological state South Bug and Aleksandrovskogo of storage pool is set on maintenance biogenic matters. Modern researches rotined that and here took place changes are certain, namely: on an area in the district of South Ukrainian power complex zone something the concentrations of nitrate and ammoniacal forms of mineral nitrogen and phosphatic ions grew, that testifies to the decline of selfcleansing ability of the river and is the index of process second contaminations of the river.

Paleoenvironmental reconstruction for mineral groundwater area Marcial Waters (Lake Onega catchment)

Assessment of the conditions for the formation of Marcial waters was carried out on the basis of complex isotope-geochemical studies of water, peat deposits in the area of mineral water discharge and regional climate paleoreconstruction. The dependence of the chemical composition of water and flow rate of wells on weather and climatic conditions was discovered. Variations in the chemical composition of water do not coincide in time with a change in the flow rate of wells due to the mixing of modern waters of infiltration origin and, possibly, meltwater of permafrost. The evolution of the hydrogeological system of ferrous waters after the retreat of the glacial edge from the northwestern coast of Lake Onega is shown. It is shown that a permanent aquifer was formed at the end of the Preboreal time. The distribution of iron and uranium isotopes in the peat core reflects a change in the redox conditions due to climate change and the participation of meltwater in the groundwater flow.