ASSIMILATION CAPACITY OF THE MARGINAL FILTER OF THE ECOSYSTEM OF THE ESTUARINE COAST OF THE VOLGA

According to the data of long-term observations, the assessment of the degree of impact of copper and zinc on the ecosystem of the shallow part of the estuarine coast of the Volga River was carried out. There are the ideas of the marginal filter and the assimilation capacity were used in the article. The calculation of the assimilation capacity for a marginal filter significantly based on the dimensional characteristics, such as the estuarine region of the Volga River, was carried out at several points located within the estuarine seashore. In this work the century-old sections of the state observation network were used. It can be seen from the calculated data that the value of the assimilation capacity is subject to significant intra-and inter-annual fluctuations. The main parameter determining the volume of the assimilation capacity of copper and zinc is fairly called the flow of the Volga River. According to the results of the study, it can be argued that the observed level of copper and zinc runoff into the Caspian Sea is completely assimilated in the shallow part of the seashore.

Identification of matter flows in marginal filters of rivers (based on the principles of thermodynamics)

Material and energy flows in the marginal filters of rivers identified based on the analyses of the environmental fate of polycyclic aromatic hydrocarbons (PAH): Anthracene (An), Phenanthrene (Phen), Naphthalene (Naph), Pyrene (Py), Fluoranthene (Flu), Chrysene (Chr), Benzo[a]pyrene (BaP), Perylene (Pl). Experimental data on the components of the aquatic system of the marginal filter of the Northern Dvina River allow us to consider the processes of phase transitions of PAHs at geochemical barriers (GCB). Based on the principles of thermodynamics, a phenomenological model of migration and the formation of the most persistent PAH associations on the barriers is formed. The predominant possibility of PAH migration on suspended material, including biota, is shown. The probability of PAH accumulation between the most important components of aquatic systems was assessed according to the conditions of their migration activity in various zones of the marginal filter. Active and passive PAHs were determined in terms of their migration and accumulation in the components of aquatic systems. The role of PAHs as a reliable indicator of thermodynamic processes, including the development of technogenesis, is estimated.

Geochemistry of suspended matter in the Volga river marginal filter

The first data on the long-term study of marginal filter (MF) of the Volga River is presented. The concentrations of suspended particulate matter, suspendforming chemical elements and microelements are considered. Ratios of enrichment suspension by chemical elements relative to the upper lithosphere are calculated. as well as their interrelations at different stages of the MF. It is shown that the sedimentary substance supplied by the sea with river flow, changes radically, both quantitatively and qualitatively.

Volgian–early berriasian marginal filter in the West Siberian marine basin and its influence on sediment distribution

The West Siberian marine basin of the Volgian–initial Berriasian ages is described. It is shown that a marginal filter (according to A. P. Lisitsyn) functioned in the basin. The main mass of terrigenous sediments was deposited within the eastern margin of the sea. The central part of the basin only received a small amount of the terrigenous material. Water area of the West Siberian Sea was 2 mln 530 thou km2; eastern marginal filter, 535 thou km2; and open epicontinental marine basin, 1 mln 994 thou km2. Depth of the Volgian Sea was 500 m. Mass of sediments in the West Siberian Sea by the end of late diagenesis was 228.4 Tt (recalculated to the anhydrous material), with sediments in the eastern marginal filter accounting for 121.7 Tt. Bioproductivity of the Volgian–Berriasian West Siberian Sea was extremely high. The mass of living matter was composed of archaea, bacteria, and protozoan unicellular eucaryotes (organic-walled), as well as organisms with the siliceous (radiolarians) and carbonate skeleton (foraminifers and others). The rock mass formed from sediments of the central deep-water part of the basin at the stage of diagenesis was 106.7 Tt (recalculated to the anhydrous material), including the mass of organic matter (OM) accounting for 15.8 Tt; mineral (siliceous and carbonate) relicts of organisms, 67.8 Tt; and allothigenic components (clay minerals and iron hydroxides), 23.1 Tt. Analysis of the composition of kerogen (polymerlipids) revealed that the amount of OM transported to sediments was 15–20 times higher than the present-day amount in rocks of the Bazhenov Formation. At the stage of early diagenesis, the OM mass in sediments was as high as 235–320 Tt (recalculated to the anhydrous material). The Bazhenov Sea represented a huge natural ecosystem favorable for the generation, reworking, and accumulation of living matter relicts. At the stage of catagenesis, unique oil-andgas resources were generated from OM masses deposited in this system.