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1.
V. D. Strakhovenko D. A. Subetto E. A. Ovdina N. A. Belkina N. A. Efremenko A. V. Maslov 《Doklady Earth Sciences》2018,481(2):988-992
The results of studying the structure and mineral composition of the Upper Holocene bottom sediments of Lake Onega are presented. It is established that there are two types of columns of bottom sediments, for which stratification of layers and formation of Fe–Mn crusts are determined by the diagenesis processes occurring under physicochemical conditions of sediment accumulation according to two scenarios. The distribution spectra of rare-earth elements (REEs) are different in the indicated types of columns, which is apparently attributed to the differences in the oxidation–reduction conditions at the water–sediment interface during the formation of REEs and possibly to the influence of hydrothermal processes. 相似文献
2.
V. D. Strakhovenko V. G. Kabannik I. N. Malikova 《Lithology and Mineral Resources》2014,49(3):213-227
Regularities of the formation of bottom sediments down to a depth of 1.2 m, as well as factors governing the composition of sediments, waters, and soils in the catchment area of the lake, are discussed. It has been established that the chemical composition of lacustrine sediments is closely associated with the composition of soils in the ambient watersheds, and the soils, in turn, are associated with the composition of the soil-forming rocks. The available data suggest an extremely irregular contamination of the lake system by technogenic radionuclides within the water area. Maximum radiocesium contamination of lacustrine bottom sediments is 350 mCi/km2 (recalculated to year 2000). Concentrations of elements (Cu, Zn, Cr, Ni, Co, Mg, Be, Sb, Mn, and others) in bottom sediments, water, and soils in catchment areas of Lake Kolyvan do not exceed the background values (except for the Hg content in bottom sediments), suggesting that the area under consideration is not contaminated by inorganic technogenic components. 相似文献
3.
Komova Anastasia Melnikova Anna Namsaraev Zorigto Romanov Roman Strakhovenko Vera Ovdina Ekaterina Ermolaeva Nadezhda 《中国海洋湖沼学报》2018,36(6):1993-2001
The Baraba and Kulunda steppes are located in southwestern Siberia in an area with an arid continental climate. This paper presents results of the first study of the hypersaline Lake Krasnovishnevoye(Baraba steppe, TDS(total dissolved solids)=297 g/L, pH 7.88). The major chemical, mineralogical and biological features of the lake were studied and compared to those of Lake Malinovoe, a typical saline neutral lake of Kulunda steppe(TDS=396 g/L, pH 7.63). The phytoplankton composition and the culturable diversity of anoxygenic phototrophic bacteria from Lake Krasnovishnevoye correspond to the ones in the Kulunda lakes. Nevertheless, the peculiarities of water composition and regime of Lake Krasnovishnevoye reduce the biodiversity to prokaryotes and unicellular algae. 相似文献
4.
The distribution of radioactive Cs and heavy metals (V, Cr, Mn, Co, Ni, Cu, Zn, Cd, Hg, and Pb) in the lichen-substrate system and in lichen tissues were examined using the example of Cladonia genera. The upper podetia-lower podetia-dead podetia-base-substrate system was sampled at 32 sites in Novosibirsk oblast and Altai administrative territory, 16 of which were selected for detailed studying of the trace element distribution in the upper and lower podetia using cold press and the modified Dexter technique. One in vivo and two in vitro experiments simulated the influence of metal-rich atmospheric fallouts on the lichen carpet. The lichen carpet was irrigated by solution of metal nitrates (Co, Cu, Zn, Cd, Hg, and Pb) in the former case and loaded in these solution during the latter experiment. The experiment performed in the laboratory conditions (in vitro) was aimed at studying the dynamics of metal accumulation in lichen constituents and their subsequent extraction with distilled water to monitor metal sorption on the podetium cell walls. The metal contents and the activity of radioactive Cs in the lichen samples, including lichen cell sap, as well as in the base and substrate, were determined by atomic-absorption and gamma spectroscopic methods. In terms of accumulation, the elements are subdivided into two groups. The lowest contents of Group-1 elements (137 Cs, Zn, Cd, Hg, and Pb) were found in the substrate, and the highest contents, detected at the base and dead podetium, are presumably of technogenic origin. The Group-2 elements (Cr, Mn, Co, Ni, and Cu) enrich the substrate. It was established that the elements are mainly accumulated in lichens in cell walls and the membrane. The lichen sap and water-soluble compounds of protoplasma contain less than 0.1% of the total element content in the tissue. Most Zn, Cd, Co, and Pb ions (about 80% of the total absorbed amount) migrated from experimental solution into lichen cells during the first 12 h. 相似文献
5.
Morphology and mineralogical and geochemical compositions of freshwater ferromanganese nodules of Ol’khon Island (Sasa Formation) and Kulunda Plain (Lake Porozhnee) were studied. The study has shown rhythmic structures of the nodules, formed by macro- and microlayers with mineralized microflora. The layers are composed of either crystalline Mn mineral phases and finely dispersed Fe phases (Lake Porozhnee) or, on the contrary, crystalline goethite and X-ray amorphous Mn phases (Ol’khon Island). Separation of Mn and Fe mineral phases in the nodules proceeded during their formation and diagenesis. The freshwater nodules show both high (Lake Porozhnee) and low (Ol’khon Island) Mn/Fe ratios. The predominance of Fe phase in the Ol’khon nodules accounts for their high contents of REE, including Ce. The Porozhnee nodules grew, most likely, more rapidly, which is reflected in their low REE contents and Ce anomaly. The examined chemical and mineral compositions, textures, and structures of the nodules testify to the low-temperature hydrothermal source of their ore substance. 相似文献
6.
V. D. Strakhovenko N. A. Roslyakov A. I. Syso N. I. Ermolaeva E. Yu. Zarubina O. P. Taran A. V. Puzanov 《Water Resources》2016,43(3):539-545
Sapropels of lake systems in Novosibirsk oblast were studied to develop a scientific basis for their rational use. Sapropels from lakes in Novosibirsk oblast have been classified based on the ash content, chemical composition, and genesis. Organic–mineral and mineral–organic calcium and mixed sapropels of macrophyte and macrophyte–plankton genesis have been shown to be predominant by far among sapropel deposits in lakes in Novosibirsk oblast. 相似文献
7.
The Tazheran lakes are located compactly in the small Tazheran steppe area. Their bottom sediments are predominantly various calcite-dolomite carbonates, and their waters are rich in uranium. The studies have shown that the main process in these lakes is chemogenic carbonate precipitation with the participation of carbon dioxide formed through the bacterial destruction of organic matter. For thermodynamic modeling of the composition of bottom sediments, we chose two lakes with different basic parameters. Calculations were made for the 15-component heterogeneous system H2O-Na-Ca-Mg-K-Sr-Ba-Si-Al-Cl-C-S-Fe-U-Mn including particles in the solution, minerals, and gases at 25 °C and 1 bar. As starting information, we used the obtained analytical data on the natural composition of waters and bottom sediments. The results show that calcite-dolomite carbonates are predominant in the bottom sediments and the destruction of organic matter results in reducing conditions. This confirms the hypothesis of the formation of mineral phases of U(IV) during diagenetic processes in the bottom sediments of the studied lakes. 相似文献
8.
Shkolnik S. I. Letnikov F. A. Strakhovenko V. D. Letnikova A. F. 《Doklady Earth Sciences》2016,471(1):1208-1212
The first data on the structure, textural features, and geochemical and mineral composition of Fe–Mn nodules of the Sasin Formation, Olkhon Island (Baikal), have been determined. A significant role in the formation of the nodules was played by hydrothermal processes with varying contributions of hydrogenic factors. The presence of reduced inclusions in the nodules and their textural features indicate the presence of various components of organic matter in the nodules, creating the conditions for local concentration of ore components. Activation of hydrothermal processes is typical for the Baikal Rift Zone in the Late Miocene–Early Pliocene, which is reflected in the composition of Fe–Mn nodules from the Sasin Formation.
相似文献9.
Gaskova Olga L. Strakhovenko Vera D. Ermolaeva Nadezhda I. Zarubina Eugene Yu. Ovdina Ekaterina A. 《中国海洋湖沼学报》2017,35(4):956-966
The Kambala and Barchin brackish lakes(Baraba steppe,southern West Siberia) contain an organic-rich sapropel layer that was formed in oxygen-depleted waters.We measured the bulk sediment elemental composition,the water chemistry and determined the mineralogical composition and predominant biota species(Diatoms and Cyanobacteria in phytoplankton community respectively) in the lakes.The result indicates that the first lake has a siliceous type of sapropel and the second a carbonaceous one.A computer thermodynamic model was developed for chemical interaction in water-bottom sediment systems of the Kambala and Barchin Lakes.The surface sodium bicarbonate waters are supersaturated with respect to calcite,magnesite(or low Mg-calcite),quartz and chlorite with minor strontianite,apatite and goethite(pH8.9-9.3,Eh 0.3 V).Nevertheless,it is shown that during sapropel deposition,deep silt waters should be anoxic(Eh0 V).The virtual component CH_2O has been used to create an anoxic environment suitable for pyrite formation due to the biotic community impact and abiotic reduction.Thermodynamic calculation has shown that silt water is not necessarily euxinic(anoxic and sulfidic).Depending on Eh,sulfate sulfur can dominate in solution,causing the formation of gypsum together with pyrite.An attempt was made to find a reason for solution supersaturation with respect to Ca and Mg ions due to their complexation with humic acids. 相似文献
10.
Nodules of various compositions, including ferromanganese nodules, have been found in bottom sediments of an artificial reservoir
in the central Altai Territory. The nodules were formed in the alkaline environment against the background of a high carbonate
content and saturation with oxygen. The rate of nodule growth is no less than 1.7–1.8 mm/yr and the pH value of water varies
from 8.0 to 9.7. Fe and Mn contents in soil and loam of the drainage area are lower than the global clarke value, whereas
Ca, K, and Na contents are much higher. The main mass of bottom sediments in the reservoir is markedly enriched in Cd, Mg,
Mn, Sr, Ni, Cr, Sb, V, and Pb, but they are depleted in Cu, Mo, Zn, and Li, relative to the soil and loam. Elements in ferromanganese
nodules are arranged in the following way in terms of the decreasing concentration coefficient: Mn (27) > Ba (13.4) > Co (10.7)
> Mo (9.2) > Cd (5.35) > Ni (3.88) > V (3.52) > Cu (3.3) > Fe (3.2) > Sb (2.17) > Sr (2.04) > Pb (1.5) > Zn (1.43) > Cr (1.1)
> Li (0.78) > Mg (0.75) > Na (0.69) > K (0.67) > Ca (0.51). The microelemental composition of nodules in the reservoir qualitatively
fits the composition of ferromanganese nodules in seas and oceans. However, the contents of major ore elements (Ni, Cu, Co,
Zn, Pb, Mo, and V) in ferromanganese nodules from the World Ocean are much higher than in nodules from the examined reservoir. 相似文献