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Despite the increasing water and sediment pollution in the western part of the Northern Caspian Sea, the quality of its marine environment has never been assessed through bioindication, largely due to methodological issues. In this article, the method of standards, which involves comparing the species composition between the polluted and clean (reference) sites, was used for the bioindication of organic pollutants in the Northern Caspian Sea. The study area was segmented based on isobaths. The segments were determined depending on the range of depths inhabited by zoobenthos species and their ecological valence to oxygen. The depths with a sufficient abundance of oxyphilic zooplankton species (bioindicators) to apply the method of standards were located. The obtained results show that the method of standards is a good and reliable choice to assess the marine environment quality in the Northern Caspian Sea at isobaths of 6–9 m and within depths of 14–18 m for polluted and reference sites. However, the sediments must contain shells, sand, and siltstones. Therefore, while the method of standards has clear merits, it does not suffice for the rest of the Caspian Sea area.

There’s made an attempt in the work to estimate the bentos population of the Northern Caspian Sea by mathematic modelling methods. At use of the given method probably considerably to improve the forecast of the general admissible fishes in this area.

In the article is in details considered the technology of investigation and an oil recovery in the eastern part of Northern Caspian Sea. It is shown that the most negative influence will test the benthos of the water area. Materials on structure, seasonal dynamics and biomass of groundorganisms of eastern part of the Northern Caspian Sea are resulted.

The 26 strains microorganisms - degradation oil have been isolated from shelf water North Caspian. The high emulsifying ability relative to benzine, kerosene and diesel-fuel oil relevantly were possessed the 11 strains. The 4 cultures exhibiting degradation of oil rates 43-49 %, respectively, were selected.

The regularity of aquatic vegetable associations formation in brackish and fresh river water in the Volga rivers foredelta and the Northern Caspian in period of the Caspian Sea level raising are analyzed. The species associations with predominance of Poaceae, Potamogenaceae and Cladophoraceae families are given. In conditions of the further fluctuations of level of Caspian Sea, basis for long-term monitoring for successonal changes in vegetable associations and biocenoses connected with them, including ichtyofauna is suggested.

This study was carried out in the northern Caspian Sea on Gidrobiolog vessel in summer 2006 to assess the abundance and species composition of sturgeons. We used bottom trawl (9m) and gillnets with mesh size 60, 110, 250 and 29Omm. Totally 104 sturgeons were caught which included ten Acipenser guldenstadtii (69.9%), two Acipenser persicus (15.4%) and one Acipenser stellatus (7.7%) in the trawl samples. The species caught by gillnet were 34 Acipenser guldenstadtii (37.4%),53 Acipenser persicus (58.2%) and four Huso huso (4.4%). The average total length and weight of Acipenser guldenstadtii caught by trawl were 65.8±5.14cm and 1248.5±495.75g respectively and for those caught in gillnet were 83.14±2.99cm, 3101±443.66g. The average total length and weight of Acipenser persicus caught by gillnet were 75±3.60cm and 1806.79±158.05g.

The distribution, sedimentology, and age of early Holocene Mangyshlakian deposits beneath the northern Caspian Sea are studied. Analyses and interpretations derive from high-resolution sub-bottom profiling, lithological analysis of core sections and boreholes, biostratigraphic analysis of mollusc shells, and radiocarbon dating. We show that the Mangyshlakian deposits overlie Upper Pleistocene Khvalynian deposits, filling valleys and depressions that formed during lower water levels, similar to present lacustrine water bodies (ilmeni) of the Volga Delta. Transgressive marine Holocene Neo-Caspian sediments that are filling facies overlie the Mangyshlakian deposits. The deposits are composed of both organogenous and terrigenous materials. The flora and fauna in the sediment indicate deposition into freshwater, differing from marine biota in the underlying and overlying sediments. Eighteen radiocarbon ages indicate that the Mangyshlakian deposits accumulated between 9 and 12 ka. [ABSTRACT FROM AUTHOR]

The Lower and Middle Volga basin regions border the Caucasus and Central Asia in the South. These regions are important in the study of the neolithisation process in Europe and the chronology of Neolithic cultures is of great significance in this respect. New 14C dates of different organic materials from archaeological sites in these regions have been obtained in the last five years. According to these data, the beginning of neolithisation in North Caspian region can be dated to the beginning of the 5th millennium BC; but in the Povolzhye it happened at least a millennium earlier.

Data on long-term studies (1948-2006) of the quantitative development and distribution of the invasive mollusk Mytilaster lineatus in the northern part of the Caspian Sea in different periods of formation of the marine ecosystem are presented. [ABSTRACT FROM AUTHOR]