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51.
Data on the mineral composition of sedimentary matter and its fluxes in the sediment system of the Caspian Sea are presented. River runoff, aerosols, particulate matter from sediment traps, and the upper layer (0–1 cm) of bottom sediments are considered. The contents of detrital minerals (quartz, albite, and K-feldspar), clay minerals (illite, chlorite, and kaolinite), and carbonates (calcite, Mg-calcite, dolomite, aragonite, and rhodochrosite) are determined. Gypsum was found in bottom sediments but is absent in the other object of the sediment system.  相似文献   
52.

Studies of lakes at different stages of separation from the sea have been carried out on the northwestern coast of Kandalaksha Gulf of the White Sea. At the end of the winter period, from March 16 to 29, 2013, the lakes Kislo–Sladkoe, Trekhtzvetnoe, Nizhnee Ershovskoe, Ermolinskaya Bay and snow near the pier of Pertsov White Sea Biological Station of Moscow State University (WSBS MSU) were studied. The isotope characteristics of the water of lakes, ice and snow, the distribution of salinity, temperature, and hydrogen sulfide content were studied.

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53.

The contribution of different geochemical processes in the accumulation of metals in dispersed sedimentary matter collected by ADOO was estimated for the first time for the White Sea system. The contents of Al, Fe, Cr, Ni, Со, and Мо (from 60 to 90% of the total content) are mainly controlled by terrigenous processes. The group of geochemically mobile elements includes Mn, Cu, Pb, and Cd; the sum of their forms 1–3, which include the contribution of absorption−desorption and formation of authigenic hydroxides and organic compounds, accounts for, on average, from 52 to 83 Mn %. With increasing water depth, the fraction of the lithogenic form remains either constant or increases insignificantly. In contrast, Mn shows a sharp increase in geochemically mobile forms, heavy metals (Pb, Cu, Mo, Co, and Cd) of which are associated with.

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54.
The descent of a large quantity of dust responsible for bright colors of atmospheric precipitation in the temperate, subpolar, and polar zones of the northern hemisphere is rarely observed [1–5]. In the twentieth century and in the beginning of the twenty-first century in the northern part of European Russia, such events had not been registered right up to March 25–26, 2008. At that time in some parts of the Arkhangelsk region, Komi Republic, and Nenets Autonomous Area, atmospheric precipitation as moist snow and rain responsible for sand and saffron colors of ice crust formation on the snow surface was observed. Thus, due to detailed mineralogical, geochemical, pollen, diatom, and meteorological investigations, it was established that the main source of the yellow dust is the semidesert and steppe regions of the Northwest Kazakhstan, and the Volgograd and Astrakhan regions, Kalmykia.  相似文献   
55.
Research on sedimentogenesis and geochemistry of the Arctic Ocean over the last 10–20 years has allowed direct (in situ) studies to be made for all types of sedimentary matter that mix together and form the bottom deposit. Contrary to common knowledge, river sediment turned out to be insignificant; instead, more important is the dispersed sedimentary matter (suspension) from the atmosphere, cryosphere (snow, ice), marine water, riverine water, biosphere (plankton and benthos), and anthroposphere (all types of pollutants), supplemented by the endogenic mater supplied from spreading zone of the Gakkel Ridge. The mixture is dominated by sedimentary material discharged from sea ice; hence, this type of sedimentogenesis is referred to as the ice-rafted marine sedimentogenesis.Application of new methods and tools (including satellites, remote hydrooptical, hydrophysical, and hydroacoustic survey, etc.) and in situ analyses produced measurements of content, composition, and characteristics of all types of dispersed sedimentary matter, its fluxes (mg/m2/year), vectors of movement, and rates for different segments of the Arctic Ocean; observations were carried out continuously on different time scale, from hours–days to seasons and dozens of years. It is a new approach to the study of sedimentary matter that opens up new possibility for a 4D quantitative sedimentology.  相似文献   
56.
During the summer periods of 2003–2005, the spatial and vertical distributions of the suspended particulate matter and bacteria in stratified and homogeneous waters of the White Sea was studied. The results of the study of various quantitative characteristics of the suspended particulate matter (first of all, the area of the surface and the volumetric and mass concentrations) and the abundance of microorganisms in the water are discussed. A direct correlation between the value of the surface area of the suspended particulate matter and the total number of bacteria in the water is revealed. However, it was manifested only during the early summer period of the observations and was not expressed at the end of the summer. The enhanced surface area of the suspended particulate matter can indicate the higher biochemical activity of its particles. The influence of the pelitic fraction on the bacteria abundance in different parts of the sea during the summer is estimated.  相似文献   
57.
58.
The first results of studies of vertical fluxes of sediment particles using the sediment traps at the Trans-Caspian section are presented. The flux values and distribution regularities are established. The fluxes of particles forming the sediment are also determined. The intra-annual variability in the fluxes corresponds to the seasonal variability of the biological activity. Above the northern slope of the Derbent Basin, the maximum vertical fluxes are recorded in the winter, which is caused by the intensification of the near-bottom currents.  相似文献   
59.
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