Bottom Sediments Of Water Bodies Research Articles

Sorption behaviour of neptunium in marine and fresh water bottom sediments in Far East area of Russia (Lake Khanka and Amur Bay)

The concentration and sorption behavior of 237Np on the bottom sediments of water bodies in the Far East region of Russia (Lake Khanka and Peter the Great Bay) were studied for the first time. The 237Np concentrations vary from 1.06 × 10−6 to 4.43 × 10−5 mBq g−1 in the bottom sediments of Lake Khanka and from 1.05 × 10−4 to 2.52 × 10−3 mBq g−1 for Amur Bay. The experiment on the adsorption of Np on marine and lake sediment showed that it is sorbed through complexation with silicates (albite, leucite). The Np sorption isotherm on marine sediments is described by the Langmuir equation; the distribution coefficients (Kd) of Np vary from 57 to 588 mL g−1. For lake sediments, the isotherm is described by the Henry equation; the Kd value reaches 935 mL g−1.

Distribution and accumulation of heavy metals in the catchment catenary complex and bottom sediments of the water body in an urban environment

Problem Statement. The pollutant intake into water bodies is one of the issues of urban areas. The pollutant input from the residential area of the city with surface runoff can many times exceed the input of pollutants from industrial and recreational areas, as well as from point pollutant sources. The objective of the study is 1) assess the distribution of chemical elements in catchments of water bodies in an urbanised area, 2) accumulation of chemical elements in solid matter of bottom sediments of surface water bodies with catchments in the functional areas of the city, 3) identify the main mechanisms of transfer of elements in solid matter from catchments to water bodies. The study was conducted on the example of Ekaterinburg (Russia). The material for the study consisted of the results of a landscape environmental and geochemical survey carried out in the city area in 2019–2021. Results. The distributions of element concentrations between functional landscape zones in the catenaries of the Kharitonovsky Garden and Chemodanchik reservoir catchments in Ekaterinburg were obtained. The distributions of metal concentrations in the catchment components show a tendency for the transfer of substance of different origin from the landscape components by lateral migration flows to the local basis of denudation (a drainless surface water body). At the same time in the bottom sediments of the reservoir there is a multiple accumulation of both pollutants and elements of typomorphic association. Dust fractions are the main carrier of contaminants in catchments.

The concentrations of artificial and natural radionuclides in the bottom sediments of south-west Altai territory water bodies

The purpose of the research is to study and analyze the environmental condition of small streams and reservoirs in the southwestern part of the Altai Territory (Russia), which were previously exposed to radiation as a result of nuclear tests at the Semipalatinsk test site. Conducting the research, the authors obtained the results of studying the content of artificial and natural radionuclides in the bottom sediments of the water bodies under investigation. Sampling of bottom sediments and their analytical studies were carried out in 2020–2022. The sampling involved measurements of the dose rate of bottom sediment gamma radiation. Having dried and ground the samples, the authors measured the flux density of alpha and beta particles from the surface. Laboratory studies of the samples were carried out using highly sensitive analytical equipment including an ORTEC GEM25P4-70 gamma spectrometer, an Alpha Analyst A1200-32AM CANBERRA alpha spectrometer, and a TRI-CARB 3110TR PerkinElmer beta spectrometer. The activities of natural radionuclides (potassium-40, thorium-232, radium-226) and artificial radionuclides (americium-241, plutonium-239+240, cesium-137 and strontium-90) were identified in the bottom sediments. It was determined that the radiation parameters of bottom sediments of water bodies in the southwestern part of the Altai Territory do not exceed the standard level, and the remains of traces of nuclear tests that took place at the test site are not found in the studied water bodies today.

ОСОБЕННОСТИ ФОТОМЕТРИЧЕСКОГО ОПРЕДЕЛЕНИЯ ОРГАНИЧЕСКОГО УГЛЕРОДА В ДОННЫХ ОТЛОЖЕНИЯХ

Background. Organic matter in bottom sediments originates from plants and animals as a metabolic by-product; it determines biological productivity of a water body and physical and chemical properties of its bottom soils, enriches its aquatic environment with biogenic elements, and provides nutrients for its benthic communites, on which, in turn, feed benthophagous fish species. The most reprepresentative indicator of the organic matter in bottom sediments is organic carbon. Relevance. Currently, for determination of the organic carbon directly in bottom sediments, either expensive equipment or certified methods approved for soils are used. Aim. This work presents the results of development and validation of the method for quantitative determination of organic carbon in bottom sediments. Methods. The developed modification of I.V. Tyurin’s method is based on photometric detection of trivalent chrome that is equivalent to the content of oranic carbon after oxidation of the organic matter in bottom sediments in chromosulfuric acid. Chloride interference was precluded with silver sulphate; as a reference standard, the State Standard Sample of glucose was used for the first time. Results. This method has been tested on the bottom sediments of the Azov Sea, and the results are found to be in compliance with those obtained from the investigations conducted by the traditional Tyurin’s method with silver sulphate. This method does not require expensive equipment and is applicable for mass determination. Conclusion. Based on the results of this investigation, a metrological certification of the developed method has been conducted; it regulates the procedure for determination of carbon mass fractions in the bottom sediments of water bodies in the range from 0.3 to 16.0 %.

Microelement composition of bottom sediments of water bodies in urban conditions

Microelement composition of bottom sediments of water bodies in urban conditions

Methodological aspects of a new method for determining the mass of oil in bottom sediments of water bodies

A method is proposed for determining the mass of oil pollution per unit area of bottom sediments of water bodies, which makes it possible to associate pollution not only with the concentration of pollutants, but also with the area of the reservoir. The approach relates to the field of environmental protection, in particular to the analytical control of the content of oil pollution in mineral, organogenic and mixed bottom sediments. It can be used for environmental monitoring of polluted water bodies, for assessing the damage caused to a water body, and for planning treatment works. The method for determining the mass of oil pollution per unit area of bottom sediments of water bodies includes sampling, drying the sample to an air-dry state, extraction of oil products from bottom sediments, chromatographic separation of oil products from associated organic compounds of other classes, quantitative determination of oil products by absorption intensity in the infrared spectrum. A survey of 88 oil-contaminated reservoirs within the Samotlor oil field in the north of Russia was carried out, in which the proposed method was tested.

ENVIRONMENTAL STATE OF SURFACE WATERS AND BOTTOM SEDIMENTS IN WATER BODIES OF THE SOUTHWESTERN PART OF THE ALTAI TERRITORY

Ecological research findings on surface waters and bottom sediments in water bodies of the southwestern part of the Altai Territory are presented. Samples were collected and analyzed between 2020 and 2021. Activities of natural (40К, 226Ra, 232Th) and artificial (241Am, 239+240Pu, 137Cs and 90Sr) radionuclides were determined in bottom sediments, research into the content of heavy metals (copper, zinc, lead and cadmium) in surface waters and bottom sediments was undertaken. As a result, it was found that radiation parameters of bottom sediments in water bodies of the southwestern part of the Altai Territory did not exceed the regulatory level. No residual nuclear plumes at the Semipalatinsk Test Site are currently detected in water of water bodies of interest. The content of heavy metals in bottom sediments does not correspond to the regulatory level. Ground water contamination with heavy metals was not detected.

Diffusion of 239,240Pu Global Fallout in Bottom Sediments of Water Bodies

Diffusion of 239,240Pu Global Fallout in Bottom Sediments of Water Bodies

Analysis of atmospheric emissions in Murmansk and their relationship with pollution of urban lakes

The main sources of anthropogenic emissions into the atmosphere of Murmansk are emissions from thermal power plants and boiler houses operating on fuel oil. As a result of the analysis of the dynamics of pollutant emissions from stationary anthropogenic sources for the period 1997-2019 it has been established that the level of air pollution is assessed as low; there is a tendency towards a decrease in gross emissions from stationary sources. The main pollutants from thermal power plants are sulfur dioxide, nitrogen oxides, carbon monoxide, formaldehyde, and benzo(a)pyrene. Together with gaseous and liquid substances, fuel oil ash and products of incomplete underburning of fuel, which include heavy metals V, Ni, Cr, Pb, Fe, Sn, enter the atmospheric air. Technogenic compounds of heavy metals and other pollutants from the enterprises of the power unit, falling out with dust or precipitation on the surface and catchment areas of lakes, affect the formation of the chemical composition of surface soils, waters and bottom sediments of water bodies. This is reflected in an increase in the concentration of heavy metals (in particular, V and Ni) in the water and bottom sediments of the lakes of Murmansk in comparison with the background values.

Application of a new method for determining the mass of oil per unit area of bottom sediments of water bodies

The authors of the article draw the readers’ attention to the urgent problem that is the assessment of the pollution of bottom sediments of water bodies with hydrocarbons in the form of oil and oil products. When conducting surveys of water bodies, the determination of the content of oil or oil products in bottom sediments is expressed in grams per kilogram of precipitation in an air-dry state. Information in this form cannot be associated with the mass of oil at the bottom of the water body, what is very important when designing treatment works and calculating damage to aquatic biological resources. The method for determining the mass of oil pollution per unit area of bottom sediments of water bodies has been proposed and tested, what makes it possible to associate pollution not only with the concentration of pollutants, but also with the area of the reservoir.

ОЦЕНКА СТЕПЕНИ ЗАГРЯЗНЕНИЯ ДОННЫХ ОТЛОЖЕНИЙ МАЛЫХ РЕК РОСТОВСКОЙ ОБЛАСТИ

Purpose: to study the degree of pollution of bottom sediments of small rivers of the Rostov region. Materials and Methods: the research was carried out in 2019–2020 according to the decree of the Government of Rostov region of 25.09.2013 no. 595 and in accordance with the orders of the Ministry of Natural Resources and Environment no. 432 of 08.10.2014 and no. 112 of 24.02.2014. The work on monitoring the pollution of bottom sediments carried out by the authors included: samples selection, description, conservation, delivery and preparation; conducting an integral assessment of toxicity. The studies were carried out on microalgae according to the biotesting method for inhibiting the growth of unicellular algae Chlorella vulgaris Beijer and ciliates Paramecium caudatum. A sample was considered toxic if the value of the toxic effect was 50 % or more. In case of detecting high toxicity, the repeated sampling to determine the prevailing priority and specific pollutants was carried out. Results: according to the approved research program, 70 samples (33 in 2019, 37 in 2020) at 21 water bodies were selected. As a result of an integrated assessment of the toxicity of bottom sediments of water bodies, an excess was revealed only in two samples taken in 2019 at the site of the river Temernik. Conclusions: the results of biotesting did not reveal an excess of the permissible toxicity values in all areas of water bodies, except for the river Temernik, where a slight excess was revealed (55 %). In this case, when forming a program for the environmental protection measures implementation, more attention should be paid to a number of other environmental problems of water bodies in the region, among which a special place is taken by low water associated with both climate change and excessive water consumption for the needs of economic activities, land plowing to the water's edge, washing out dams and other blocking structures, including due to improper functioning of culverts.

МЕТОДИКА РАСЧЕТА СТРУЙНЫХ АППАРАТОВ, ИСПОЛЬЗУЕМЫХ В ГИДРОМЕХАНИЗАЦИИ

Purpose: to develop a methodology for calculating jet devices used in hydromechanization for the development of soils and cleaning reservoirs from sediments using the results of our own research and the theoretical and empirical dependences presented in the literature. Materials and Methods: on the example of a diagram of an annular two-surface jet ejectors with increased energy characteristics, a method has been developed and the calculation of the relative and actual geometric and hydraulic parameters of its elements is shown for use as a suction tip on suction dredgers at the necessity to increase the suction height and development depth of centrifugal dredgers. Results. Based on the initial data (the values of the hydraulic resistance coefficients of the inlet section, diffuser, nozzle, the distance from the nozzle edge to the beginning of the mixing chamber, mixer, operating parameters of the pump – pump head and flow rate, pipeline diameters), the pulp density in the suction nozzle, the weight coefficient of ejection, geometric characteristic, relative optimum head, actual heads of the jet apparatus and pump-blower, volumetric total flow, volumetric consistency of the pulp in the suction pipeline, performance over the ground, actual dimensions. Conclusions: the developed methodology will allow calculating the optimal dimensions of jet enjector of a new design and developing a design for the suction tip of a suction dredger for various in pressure, flow rate and development depth of operational options for removing bottom sediments in water bodies.

Methodological Aspects of a New Method for Determining the Mass of Oil per Unit Area of Bottom Sediments of Water Bodies

A method is proposed for determining the mass of oil pollution per unit area of bottom sediments of water bodies, which makes it possible to associate pollution not only with the concentration of pollutants, but also with the area of the reservoir. The article uses the results obtained during the implementation of the project (No. 8.2.13.2020), within the framework of the Competitiveness Improvement Program of Tomsk State University.

Основные критерии оценок содержания тяжелых металлов в донных отложениях водных объектов

The main criteria for assessing the content of heavy metals in sediments of water bodies. At present, the methodology for rationing pollutants in bottom sediments of surface watercourses is clearly not sufficiently developed. There are various and significantly different approaches to the assessment of soil contamination with heavy metals. The maximum permissible concentration (MAC), which is the main criterion for assessing the levels of pollution, is not perfect and needs to be significantly adjusted. A number of methodological assessments of contamination of bottom sediments with heavy metals with comparative characteristics are considered, of which a method for estimating the anthropogenic load on a reservoir according to its geo-classes has been proposed as one of the best. The gross content of heavy metals in bottom sediments of water bodies does not give a sufficient idea of the possibility of secondary pollution of water masses and, as a result, subsequent toxic effects. A much more important indicator is their content and distribution by forms of existence in the solid phase and pore solution of bottom sediments. As a consequence, this article develops a topic for estimating possible secondary pollution of water bodies by determining the content and distribution of TM by forms of existence in the solid phase and pore sediment solution.

Natural radionuclides in bottom sediments of the saline lakes. What factors determine their concentration?

Concentrations of 226Ra, 40K, 210Pb, 234Th, 238U, 232Th, and 210Po were determined in bottom sediments of 11 Crimean saline lakes. From lake to lake, concentration of all radioisotopes and their total amount varied. The greatest variability was noted for 226Ra (CV = 1.268), and the smallest for total sum of radionuclides (CV = 0.336). In all lakes, the concentration of studied radionuclides did not exceed the maximum concentrations found in bottom sediments of water bodies in different regions excepting Lake Sasyk-Sivash where 226Ra concentration was slightly higher than previously found the upper limit. There are the inter-lake differences and temporal changes in radionuclide concentrations in the bottom sediments. Salinity is not main determinant of radioisotope concentrations in the lake bottom sediments, but may modify their concentrations in some ranges. The behavior of 210Pb and 210Po under anoxic conditions differs from observed in oxic. Authors conclude that there is no any single factor itself controlling concentrations of radionuclides in the upper layer of bottom sediments in the saline lakes; there is multicausal determination. Only coupling of many factors (physical, chemical, and geochemical properties of radioisotopes, and geological, climatic, and biological) determines radionuclide distribution patterns.

Impact of urbanization on the state of water bodies and adjacent territories

The processes of urbanization of the territory of the Russian Federation lead to the growing impact of man-made factors on water bodies, especially in those cases when water bodies are located directly in the centers of urbanization, or in the zones of their influence. For water supply of economic activities, a significant proportion of river runoff is withdrawn, large volumes of untreated or conditionally clean wastewater are discharged into rivers. As a result of these processes, the hydrochemical and hydrological regimes of water bodies in urbanized areas have been greatly changed, which in turn leads to the accumulation of a significant amount of contaminated bottom sediments in water bodies, which negatively affects the quality of water and the general ecological state of water bodies. Since the negative impact of urbanization on water bodies with varying degrees of intensity has been going on for over 100 years, the volumes of contaminated sediments accumulated in water bodies, in some cases, reach critical values. Cleaning up contaminated areas of water bodies can be carried out using various sets of measures. However, the development of such measures can only be based on a detailed survey of water bodies. This paper shows that when carrying out such studies, it is necessary to take into account not only the migration of toxic substances in various adjacent environments, for example, from water to bottom sediments, from soils to plants, but also the effect of these compounds on the entire trophic chain, at the end of which there is a person. At the same time, it is necessary to note that both during the restoration work and during the operation of water bodies, it must be remembered that a water body is a single water ecosystem, a system inextricably linked with the adjacent territories.

Anthropogenic enrichment of the chemical composition of bottom sediments of water bodies in the neighborhood of a non-ferrous metal smelter (Silesian Upland, Southern Poland)

An assessment was carried out of the anthropogenic enrichment of the chemical composition of the bottom sediments of water bodies situated in an area with an urban and industrial character (63.7% of the total area). The endorheic catchments of the water bodies studied are lithologically uniform with sandy formations accounting for more than 90% of the surface area. On the basis of geoaccumulation index values, it was found that the bottom sediments of the water bodies studied were contaminated with the following elements: Cd, Zn, S, As, Pb, Sr, Co, Cr, Cu, Ba, Ni, V, Be, in degrees ranging from moderate to extreme, with lower contamination (or absence of contamination) with the same elements being found in the formations present in the vicinity and in the substrate of the basins of water bodies. It was found that one consequence of the fact that these water bodies are located in urban and industrial areas is that there is anthropogenic enrichment of the chemical composition of bottom sediments with certain basic components (organic matter, Mn, Ca and P compounds) and trace elements: Cd, Zn, Pb, Sb, As, Cu and Co, Br, Ni, S, Be, Cs, Sr, V, Cr, Sc, Ba, U, Ce, Eu and Th, with virtually no enrichment of sediments with the other basic and trace components analysed (La, Rb, K2O, Nd, Sm, Na2O, Hf, SiO2, Zr).

Physicochemical Properties of Bottom Sediments in Water Bodies in the Central and Southern Vietnam

The physicochemical characteristics of bottom sediments in inland water bodies in the Central and Southern Vietnam are presented for the first time, including particle-size distribution, organic matter content, bulk density, and natural moisture content. The main types of sediments in rivers, lakes, reservoirs, abandoned quarries, and ponds were determined. The physicochemical properties of bottom sediments in Vietnam water bodies and Volga Chain reservoirs were found to be similar. General features were revealed in the formation of bottom sediments in water bodies under humid, arid, and tropic monsoon climate.

Distribution of Mercury in Water and Bottom Sediments of the Estuary Area of the Red River (Vietnam)

The paper determined the content of mercury in water-bottom sediments and the feature of its spatial distribution in the estuary area of the Red River (Vietnam). The studies were conducted at 30 stations during the main hydrological seasons of 2014-2016 (during the flood and low water). Samples of bottom sediments were collected on the surface layer with a depth 0…10 cm. The spatial distribution of mercury was carried out using the Kriging interpolation method in ArcGIS 10.2.2. The concentration of mercury in the water of the Red River varied from 0.05 to 0.08 µg/l in low water and 0.07…0.11 µg/l during the flood. Towards the sea, the concentration of dissolved mercury decreased. The spatial distribution of the suspended form and phases of bottom sediments of mercury in the estuary area of the Red River was characterized by an increase in the concentration in the Delta watercourses towards the sea, the presence of a maximum in the marginal filter and a general decreasing gradient at the coast. The Hg content in the suspended form varied from 0.008 to 0.7 µg/l, and in bottom sediments within 0.1…1.25 mg/(kg dry weight). In river waters, the main forms of mercury were dissolved and suspended, and in the marginal filter – in bottom sediments. Bottom sediments of the estuary area of the Red River were characterized by a higher content of Hg compared to unpolluted soils in temperate and northern latitudes, as well as bottom sediments of water bodies of another region of Vietnam.

Methodology for assessment of technogenic contamination in water bodies at urban areas

The paper considers the problem of the influence of man-made load on the quality of water and bottom sediments of water bodies. The relationship of the state of the water body, the quality of the water in it and the level of contamination of bottom sediments is established. It has been shown that the rates and volumes of formation of bottom sediments and the level of contamination of their layers are different throughout the existence of a water body, which allows the use of bottom sediments as the main indicator of the ecological state of a water body, reflecting the level of anthropogenic impact on water ecosystems over time.