Chemical Composition Of Bottom Sediments Research Articles

An Investigation of the Chemical Composition of Bottom Sediments from Dried Lake Gavur of Türkiye by Using XRF and Multivariate Data Analysis

Lake sediments offer valuable information about the geographical, climatic and environmental changes. This work examined the chemical elements of eleven sediment samples from the old bottom (0-5m; 0.5m increments) of the dried Lake Gavur in Türkiye by applying XRF along with PCA and PLSR data analyses. The highest but negative correlations were observed for Sr (-0.89), S+SO3 (-0.74) and Zr+ZrO2 (-0.61) with sampling depths meaning that their concentrations were lower in deeper locations (4.0-5.0 m). In contrast, Ti+TiO2 (0.60), Al+Al2O3 (0.53) and Cu+CuO (0.51) had high and positive correlations and their quantities increased as the depth increased. The age of two samples was determined as 4752±33 BP years (2.5 m) and 5470±35 BP (5.0 m). Ca+CaO content was found as lower and Ti+TiO was higher in the deeper sediment (5.0 m) indicating rainy periods. PCA clustered the samples into two groups as deeper samples (4.0-5.0 m) and other samples (0.0-3.5m) while PLSR grouped them into three clusters as deeper (4.0-5.0 m), medium-depth (1.5-3.5 m) and shallower (0.0-1.0m) samples. PLSR model had a good performance to estimate the sampling depth from the chemical elements (R2cal=0.95; R2val=0.67) which means that the variations of the chemicals were highly dependent on the sampling depth.

Study and evaluation of the chemical composition of bottom sediments of the Volga-Akhtunisky flood

The chemical composition of the bottom sediments of the Volga-Akhtuba floodplain was assessed. Chlorides (36 mg/kg) were found to be one of the predominant anions, while calcium (27 mg/kg) and sodium (27 mg/kg) were the predominant cations. In terms of pH, the bottom sediments were weakly alkaline throughout the studies. The agrochemical composition of bottom sediments of the studied water body corresponded to lime sapropel due to the content of organic matter in them (4.21%), as well as common forms of nitrogen (0.58%), phosphorus (0.27%) and potassium (1.1%). To assess the chemical and toxicological parameters in samples of bottom sediments, the quantitative content of metals and pesticides was determined. It was found that their content does not exceed the maximum permissible concentrations. An analysis of the IR spectrum data made it possible to establish that the IR spectrum contains absorption bands characteristic of bentonite clays, which have good fertilizing and water-retaining properties.

Bottom Sediments as an Indicator of the Geoecological State of Natural Water Currents

The parameters of the natural geochemical background of ecosystems of the Lunnoye deposit area were studied and the geoecological conditions of large and small watercourses of the Yukhukhta — Yukungra interfluve were assessed according to the state of the total pollution index of bottom sediments. 27 elements of the gross content were determined by the method of emission spectral analysis. The elements that determine the geochemical specificity of the territory were revealed: Bi, Li, Sn, Y, Be, Sc, K, Th, Cs and Ra. At the time of research, the state of the surface watercourses of the territory is assessed as moderately polluted. With further monitoring, special attention should be paid to the state of the river basin Yukhukhta and especially the dynamics of changes in the chemical composition of bottom sediments of the brook. Lunny and Mramorny. The elements K, Th, Cs, Ra, Be, Zn, Pb, As, Cr, and Ni are proposed as parameters for monitoring the geoecological state of bottom sediments.

Ice Coverage of the Laptev Sea and Air Temperature Variation during Recent Centuries: Observed Data and Reconstructions Using a Geochemical Proxy

Objective: The aim was to reconstruct the climatic parameters and ice of the Laptev Sea over the last centuries and to identify the causes of their variability. Background: The ice-free water area of the Arctic Ocean has increased considerably during the summer–autumn period in recent decades, which may be attributed to several climatic and oceanographic factors. Methods: The ice-free period duration and mean annual surface air temperature were reconstructed using the transfer function technique to compare hydrometeorological data and the chemical composition of bottom sediments accumulated during the observation period. This approach was based on sub-millimeter scanning of sediments using synchrotron radiation X-ray fluorescence. The results revealed a specific feature of the variations in the mean annual air temperature over the last 400 years in the Laptev Sea region, whereby higher (up to positive) temperature anomalies, were observed during the Little Ice Age. Some discrepancies in the ice coverage and climate fluctuations were observed during the period from the end of the Little Ice Age to the beginning of the period of accelerated ice-cover degradation in the Arctic (1850–1980). These discrepancies can be caused by the beginning of global warming, which have disturbed the natural cyclicality of atmospheric processes, whereas natural variations in ice coverage were more stable. Conclusion: A joint analysis of the reconstructed variations in air temperature and the duration of the ice-free period revealed the influence of atmospheric processes on the ice conditions of the Laptev Sea.

ОСОБЕННОСТИ ПОВЕДЕНИЯ ХИМИЧЕСКИХ ЭЛЕМЕНТОВ В СИСТЕМЕ ВОДА–ПОРОДА РАЙОНА РАЗРАБАТЫВАЕМОГО КАРЬЕРА БУТОВОГО КАМНЯ В ПИТКЯРАНТСКОМ РУДНОМ РАЙОНЕ (КАРЕЛИЯ)

Актуальность. Изучение особенностей перераспределения химических элементов в системе вода–порода в районах, где ведется активная разработка месторождений полезных ископаемых, актуально ввиду потенциального влияния этих процессов на экологическую обстановку и изменение геохимических условий природной среды. В частности, это важно для выбранного района, который входит в площадь водосбора крупнейшего природного резервуара пресной воды в Европе – Ладожского озера. Целью представленного исследования является изучение выноса химических элементов водой из гранитоидных пород, вскрытых карьером, и их дальнейшего поведения в природных водах и донных отложениях района. Объектом исследования являются природные воды и донные отложения района разрабатываемого карьера бутового камня (Питкярантский рудный район, республика Карелия). Авторы проследили изменения химического состава природных вод и связанных с ними донных отложений по мере движения воды от ее сброса из карьера до впадения в речную сеть. Методы. Анализ химического состава природных вод и донных отложений проведен стандартными методами: потенциометрия, титриметрия, ICP-AES, ICP-MS. Исследования минералов в составе пород карьера бутового камня проведено при помощи LA-ICP-MS, химический состав горных пород изучен методами XRF, ICP-MS и ICP-AES. Физико-химическое моделирование форм нахождения в природных водах и осаждения минералов проведено в программном комплексе HydroGeo. Верификация модели проведена на основе анализа химического состава донных отложений. Результаты. В изученных водных объектах в отдельных точках отмечены превышения ПДК Fe, Mn, Cu, Zn, Mo, V. При удалении от карьера бутового камня снижается величина общей минерализации природных вод и содержание макрокомпонетов, а также Sr, U, V, Mo, Zn, Cd. Концентрация железа, наоборот, увеличивается ввиду роста содержания органического вещества в воде. В донных отложениях пик концентрации многих элементов (Fe, Mn, Co, Cu, Zn, Cs, Ce, La, Y) наблюдается в точке сброса воды из карьера. Максимальное содержание U отмечается чуть ниже по потоку изучаемых вод, что согласуется с данными по составу донных отложений и моделирования, которые указывают на возможность выпадения уранинита из водного раствора в водоеме, сформировавшемся при сбросе воды из карьера бутового камня и истоке ручья, берущего начало в этом водоеме. Роль органического вещества в изученных водах высока для процесса накопления железа в воде за счет образования устойчивого гидроксо-фульватного комплекса железа, а также для редкоземельных элементов за счет образования комплекса с гуминовой кислотой. Анализ распространенности, форм нахождения и осаждения химических элементов позволили заключить, что эксплуатация карьера бутового камня вносит существенный вклад в перераспределение химических элементов в изучаемом районе.

Assessment of the Bottom Sediments State After Oil Spill

The paper has deal with the monitoring of the lake bottom sediments which were contaminated by oil during emergency spill. The results of geochemical study of chloroform bitumoids extracted from sediment samples showed that the processes of transformation of oil hydrocarbons lasted for 10 years since the oil spill. This is indicated a decrease in the residual oil content and changes in the chemical composition of bitumoids. The hydrocarbons content was decreasing and resinous-asphaltene components was increasing as oxygen-containing groups and bonds in the chemical structure of bitumoids. In the individual composition of hydrocarbons the significant redistribution of saturated hydrocarbons was occurring both within the homologous series and between different homologous series, the CPI coefficient and the biodegradation coefficient Prophy/nC17+nC18 was increasing. By 2017 in absence of new oil spills the chemical composition of bottom sediments had closed to a state inherent in the native organic matter of bottom sediments of coastal lake facies, which characterized by the presence of compounds typical for higher plant lipids (dominance of high molecular weight n-alkanes of composition nC23–nC33 with a significant predominance of odd homologues, a high content of oxygen-containing compounds – solid saturated fatty acids, aliphatic esters and saturated ketones).

Indicator Elements of Hydrocarbon Accumulations in the Southern Part of the Tatar Strait and the Northern Circuit of the Central Depression of the Sea of Japan

Hydrocarbons, in particular methane, in bottom sediments are able to form accumulations together with chemical elements and inorganic compounds. Such elements are indicators of the presence of hydrocarbons. Their establishment in certain areas of the water area can make a serious contribution to geological exploration. This paper examines the relationship of the areas of methane concentration and chemical composition of bottom sediments in the southern part of the Tatar strait and the northern circuit of the central depression of the sea of Japan. A connection of methane was found with elements such as S, Mn, Sr, Cu, Zn, Pb and Ni. The strong correlation of methane with S. There is a medium and weak connection of methane with Cu, Zn, Mn, Ni, Sr. The main concentration of methane observed in the western part of Terney trough and on uplift-shift disturbances of the 46th parallel. Installed indicator elements and geochemical studies can be used for further analysis of the distribution patterns of hydrocarbon deposits in the area.

Features of CU and MN accumulation by bottom sediments of the Caspian Sea

The main sources of chemical elements for aquatic organisms are sea water and bottom sediments, and the levels of chemical elements in organisms depend on the level of these elements in the environment. The Caspian Sea is a special biogeochemical province with geochemical barriers in the area of mixing of river and sea waters, therefore, the study of its biogeochemical background, the peculiarities of the chemical composition of bottom sediments is the relevance of the work. The aim of this work was to reveal the content of manganese and copper in the bottom sediments of the Caspian Sea. The study revealed low concentrations of copper and relatively high manganese in the bottom sediments of the Caspian Sea, which is primarily due to the parent rocks of the Caspian lowland, which are poor in Cu, but rich in Mn. The results of biogeochemical analysis of bottom sediments of the ecosystem of the Caspian Sea serve as material for resolving the issue of the role of biogenic transformation of microelements in the cycle of substances.

Chemistry of Bottom Sediments from Selected Karst Lakes in the Vicinity of Staszów (Nida Basin)

Abstract The aim of this study was to reveal the chemical composition of bottom sediments in karst lakes located in the northern part of Połaniec Basin (eastern part of the Nida Basin, vicinity of Staszów municipality). A field investigation was carried out in 2010 on four lakes: Duży Staw, Donica, Dziki Staw and Łajba. The contents of a very wide range of chemical elements were determined, which is a rarity. On the basis of our research, it was found that the analysed lakes differed considerably between each other in spite of their close location. In general, sediments contained fair amounts of organic substances as well as Fe, Al, Ca and Mg due to the type of source rock and soligenic lake water supply. Increased concentrations of V, Cr and Ni might be explained by the weathering of rock material. In turn, higher contents of Zn, Pb, Cu and Co in the bottom sediments from Duży Staw indicated anthropopression. The measurement results obtained in this study will allow a future comparative analysis with bottom sediments from other lakes.

Gas-Geochemical Parameters of Bottom Sediments in the Northern Part of the East Siberian Sea and Podvodnikov Basin of the Arctic Ocean

New data on the gas and chemical composition of bottom sediments of the marginal-shelf part of the East Siberian Sea, continental slope, and Podvodnikov Basin of the Arctic Ocean are presented. The genetic parameters of seven groups of epigenetic hydrocarbon gases are determined. The distribution areas of the potential oil–gas, gas–oil, and oil deposits have been revealed. Three groups of chemical elements have been specified in bottom sediments. Their maximum concentrations are related to particular geostructures of the area studied.

Пространственно-временные изменения вещественного состава донных отложений и речных вод Туганского россыпного узла (Томская область)

The changes in the chemical and mineral composition of bottom sediments and waters of the Omutnaya River (the element of the Omutnaya–Kirghizka–Tom–Ob river system) during the main phases of the water regime in 2018–2019 within the planned Tugan placer deposit (ore minerals—ilmenite and zircon) have been studied. Geochemical parameters were estimated using an inductively coupled plasma mass spectrometry method. It was obtained that the spatiotemporal changes in the gross contents of chemical elements are generally interrelated with their migration forms. General increase in the concentrations of substances in suspended form is predominant and noted in spring floods, with dissolved—in the winter low-water period. Changes in the chemical composition of bottom sediments (fraction up to 1 mm) during the year and from the source to the mouth of the river due to the influence of local geological and hydrological factors are weaker than the corresponding changes in the chemical composition of river waters. Based on the studies, it was shown that the maximum concentrations of ore elements within the halos of placer deposits are most likely under conditions of a relatively stable (geologically) decrease in the intensity of water exchange.

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).

Color and chemical composition of bottom sediments from the Kuril Basin (Sea of Okhotsk) and the Kuril–Kamchatka Trench area (Northwest Pacific)

The colorimetric method of analysis was first used to study the distribution of the color characteristics (spaces RGB and HSL) in sediment cores from the Kuril Basin of the Sea of Okhotsk and the nearby Kuril-Kamchatka Trench area of the Northwest Pacific. The statistic processing of these and in addition obtained geochemical and grain-size data made it possible to establish the controlling factors and significant relations. The most stable direct correlation is demonstrated by the characteristics of R–Mn–Mo (fine-grained oxidized sediments enriched in hydroxides of iron and manganese and related with them microelements) and H–L–SiO2 (coarse-fragmental part of sediments involving the grains of rock-forming minerals and sometimes a significant admixture of the diatom frustules). Usually, saturation S and phosphorus content gravitate to the first group of parameters, and the additive primary blue color B tends to the second group. Informative are some relations of the color characteristics, for example, the additive primary red color R and green color G (the boundary of the oxidized and reduced sediments). The admixture of the volcanogenic (pyroclastic) material can be reflected in the shift and disruption of the described relations.The results obtained show the regional conditions of sedimentation with the participation of the terrigenous, biogenic, and volcanogenic material and subsequent diagenetic redistribution of the matter. The revealed regularities together with other characteristics of the matter composition can be used for the detailed description of the sediment cores of the regions with the similar settings of sedimentation.

Chukchi Sea Ice Conditions for the Last Few Centuries: Reconstruction from Sedimentation Records

For the first time, the reconstruction of variations in the duration over several hundred years was conducted on the basis of models developed by comparing hydrometeorological observations and detailed scanning of the chemical composition of bottom sediments accumulated during the corresponding period. The gauge models for the reconstruction of air temperature and ice cover of the water area for three sites in the northern part of the Chukchi Sea have been developed. During the reconstruction, an insignificant increase in the duration of the ice-free period during the Little Ice Age was established, which does not coincide with the changes in the temperature regime that took place. It is concluded that the dynamics of the inflow of warm Pacific waters through the Bering Strait had the predominant influence on the ice regime of the Chukchi Sea.

Influence of Global Climate Changes in Past Centuries on the Chemical Composition of Bottom Sediments in the Chukchi Sea

The sedimentary cores from the southern and northern parts of the Chukchi Sea illustrate the influence of climate and environmental conditions on the chemical composition of bottom sediments accumulated at present and in the recent 500 years. The low concentration of biogenic (Ca, Br, Sr) and some redox-sensitive (Fe, Mn, Zn) elements is typical of the recent sediments accumulated in the areas with permanent ice cover and of the sediments accumulated during cold periods (Little Ice Age and especially the Maunder Minimum). The possibility is revealed of identifying cyclic changes in environmental conditions including sea ice extent in the concrete Arctic areas. This may be used to detail the regional forecast of future changes.

Chemical Composition of Bottom Sediments of the Zeya and Selemdzha Rivers as a Reflection of Drainage Area Weathering

This paper reports the results of chemical study of bottom sediments of the Zeya and Selemdzha rivers, the largest water streams of the Amur River basin. It was established that the bottom sediments are depleted in practically all analyzed major and trace elements as compared to the upper continental crust (UCC) and Post-Archean Australian Shale (PAAS). It is shown that the bottom sediments of the studied rivers are chemically close to those of the Northeastern China rivers, which is related to the similar geographical and climatic environments. Examination of major-component proportions and trace-element variations suggests that the bottom sediments of the middle reaches of the Zeya River were formed from chemically reworked sources. In contrast, the bottom sediments of the lower reaches of the Zeya and Selemdzha rivers are dominated by physically reworked rather than chemically reworked materials. It is suggested that the bottom sediments of the Zeya River downstream the mouth of the Selemdzha River were formed from material, which was supplied by the Selemdzha River and determined the main geochemical characteristics of the bottom sediments of the lower reaches of the Zeya River. This is presumably related to the fact that the upper reaches of the Selemdzha River is located mainly within the Mongol–Okhotsk fold belt, the complexes of which experienced intense tectonic shearing and brecciation. For this reason, the bottom sediments of the Selemdzha River are mainly dominated by physically reworked rather than by chemically reworked material.

FEATURES OF HEAVY METALS DISTRIBUTION IN BOTTOM SEDIMENTS OF THE RIVERS OF UKRAINE

The chemical composition of bottom sediments is an important indicator of the ecological state of both water systems and watershed areas, since contaminated bottom sediments are a potential source of secondary pollution of aquatic systems. The analysis of recent publications shows that great attention has been paid to the chemical composition of bottom sediments, however, as a rule, these studies are of a local nature, that is, they cover very small areas. This often raises the issue of criteria for assessing the ecological and geochemical status of bottom sediments, since a small number of samples does not allow correctly determining the local geochemical background. In addition, generally accepted norms, for example, the maximum allowable concentrations, do not exist for bottom sediments. In these conditions, data on regional geochemical backgrounds of pollutants are needed. The need for the implementation of the Water Framework Directive in Ukraine, which requires the introduction of water management basin-based, necessitates the determination of the geochemical characteristics of bottom sediments within the river basin territories. To study the distribution of heavy metals and determine their regional backgrounds in the bottom sediments, a database of environmental and geochemical information was used in the GIS, one of the blocks of which is information on the content of chemical elements and compounds in the bottom sediments of watercourses and water bodies of Ukraine, and the electronic map of river basins of Ukraine. Based on the analysis in the GIS of information on the chemical composition of the bottom sediments of the rivers of Ukraine (about 8,1 thousand samples), regional geochemical background of lead, zinc, copper, chromium, nickel and cobalt have been determined. The main regularities of distribution of chemical elements in bottom sediments in the territory of Ukraine are established. For the chemical elements in question, a gradual increase in their content in soils from north to south, that is, from the river basins of the Polissya zone to the basins of the Steppe landscape-climatic zone, is consistent with the geochemical features of the soil cover of the catchment areas. The increased background content of chemical elements in bottom sediments often spatially coincides with the spread of soil differences in the catchment areas, which also have a high content of these elements. The maximum background content of most heavy metals in bottom sediments is naturally clearly recorded within the Carpathian-Crimean metallogenic province. Thus, despite the long and intensive technogenic impact on the surface water bodies of Ukraine, it is necessary to note the priority of natural factors in the formation of the chemical composition of bottom sediments, at least for the heavy metals considered above.

Микроэлементный состав донных отложений малых озер как индикатор возникновения экологических рисков в условиях урбанизированной среды (Республика Карелия)

The general questions of the influence of urban environment on the development of deviations in living organisms up to the death of individual species are considered. Using the example of a study of the chemical composition of bottom sediments of six small lakes of the Republic of Karelia, a significant effect of technogenesis on the occurrence of ecological risks on the aquatic flora and fauna of an urbanized environment is shown. We have stated that the upper layers of the bottom sediments of urban lakes have increased concentrations of heavy metals in comparison with the underlying layers. The thickness of technogenically altered lake sediments for urban water bodies of Karelia is established. According to the analysis of the formulas of geochemical associations of bottom sediments of urbanized lakes, we identified priority pollutants (Pb, Sb, Cd, V, Zn, Cu, Ni etc.). These metals are associated with major environmental risks within the urban environment of the region. The patterns of distribution of individual chemical elements in the investigated lake sediments are determined depending on the geochemical specificity of the catchment area and specific sources of heavy metals. Examples of direct negative effects of heavy metals on living organisms of the aquatic environment are benthic organisms and fish. The biogeochemical potential of biota of urban water bodies to accumulate heavy metals and accompanying microelements is shown.

THE GEOCHEMICAL SPECIFICS OF MODERN SEDIMENTATION PROCESSES ON THE BOTTOM OF A SMALL LAKE LAMBA UNDER TECHNOGENIC IMPACT

The data on the chemical composition of bottom sediments of the small urban Lake Lamba located in the city of Petrozavodsk (Republic of Karelia) are presented. In this investigation we used modern precision methods for studying matter. Chemical analysis of bottom sediments of Lake Lamba was conducted using X-ray fluorescence spectrometer ARL ADVANT'X and mass spectrometer XSeries-2 ICP-MS. It was established that sediments in the lake are ferruginous (limonite) sapropels with a high content of organic matter. It is shown that the distribution of heavy metals and their accompanying microelements in the studied freshwater sediments reflects the industrial history of the city of Petrozavodsk and the general man-generated pollution in anthropogenically disturbed territories of the world. The distribution of V, Cr, Ni concentrations in the bottom sediments indicates a significant influence of the Petrozavodsk heating plant. The abnormally high Pb concentrations in the sediment layers are associated with global pollution of the environment by this heavy metal due to its input from traffic emissions. The distribution of Co, Cu, Zn, Mo, W concentrations reflects the impact of industrial enterprises in Petrozavodsk on the ecosystem of Lake Lamba.

Composition of interstitial waters and forms of sulfur compounds in bottom sediments in the northeastern Black Sea

Study of sediments and water column in the Black Sea has been carried out for a long time. However, issues of the formation of seawater and sediments in the geological (ancient) and Recent marine history remain debatable so far. Studies of the physical, biological, and biogeochemical settings in the northeastern part of the Black Sea carried out onboard the R/V Professor Shtokman in 2009 yielded new data on this region. The present paper reports the results of study of the chemical composition of bottom sediments and interstitial waters from the meridional profile extending from the Kerch Peninsula to the central part of the eastern deep-water depression.