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The conceptual basis for the creation of a forecast-analytical system that allows to predict the pollution and to control the purification of oil-containing sediments of small rivers are considered in this article. Oil content of bottom sediments creates the risk of secondary water pollution not only by substances entering the sludge. More dangerous products of degradation are formed in the result of the activity of the indigenous microorganisms, that inhabit the bottom of aquatic environment. Forecasting the dyna...

This paper presents the geochemical forms of arsenic that are present in bottom sediments of rivers and surface waters under various oxidative conditions. In summer, in the rivers with the high anthropogenic load the redox potential of bottom sediments varies from 78 mV to 255 mV (at a temperature of 16-20?C), which corresponds to oxidative and mixed oxidative-reductive conditions. It is shown that under these conditions arsenic is present in the form of insoluble arsenous acid, partially ionized arsenic acid and ...

The study of lake sediments allows to reconstruct abiotic and biotic conditions of a lake and its surrounding area. Diatom communities are commonly used in studies of water quality and being bioindicators of the lake state diatoms used for the reconstruction ecological conditions of the past. Core samples from Rubskoe Lake were collected in July 2015 and the species composition of the diatom algae, which serve as, were studied. The core covered a 13 000 years period. In 23 samples of Rubskoe Lake 30 diatom taxa be...

Bottom sediments are a specific component of aquatic ecosystems. They are actively involved in the accumulation, redistribution and mass transfer of chemical elements, including heavy metals. They can contribute to the purification of the water column, due to its depositing properties. However, they can also serve as a source of secondary pollution, as a result of the transition of pollutants into the suspended matter. The intensity of accumulation and migration of substances is directly dependent on the lithologi...

The purpose of this work is to assess the ecological state of the Moskva River on the content of heavy metals in bottom sediments by the method of L. Hokanson. The method of determining the coefficient of bottom accumulation (CBA) was also used. The content of metals was determined by the X-ray fluorescent method according to the approved procedure. The analysis of the obtained data made it possible to draw a number of conclusions. First, the average level of some heavy metals (zinc, nickel, copper, manganese) was...

An important indicator of the existing and possible pollution of any water area is the content of trace metals in bottom sediments that can characterize the level of anthropogenic load. Analysis of the content of metals in bottom sediments in different parts of the water area made it possible to establish the features of distribution of toxic metals in dependence on natural geochemical processes and to identify the areas that experience the most intensive anthropogenic load. In the paper, estimates of the spatial ...

The study of sediment transport in the coastal zone under the influence of waves and currents makes it possible to predict changes in the ecosystem of the coastal zone under various hydrometeorological conditions and anthropogenic influences. River runoff and abrasion processes are one of the main sources of solid matter entering the coastal zone, as well as one of the factors determining the changes in the granulometric composition of bottom sediments. Since the rivers of the Western Crimea are heavily regulated,...

Uranium-238 is a parent radionuclide for several radioactive stable chemical elements, which presence in the therapeutic mud can cause negative consequences for patients. This paper presents the results of the study of the U-238 specific activity in the mud sediment cores of Pelenkino Lake and Bolshoi Tambukan Lake situated in two different geological and hydrological regions in the south of European Russia. The relationship between the U-238 specific activity in the mud, its pH, Eh values and the organic matter c...