Dmitry F. Pavlov

Riverine fluxes of the persistent organochlorine pesticides hexachlorcyclohexane and DDT in the Russian Federation

The contribution of gross riverine organochlorine pesticide (OCP) transport to estuaries of Russian seas and Lake Baikal was determined to help understand OCP transboundary transfer and to provide a basis for estimating Russias contribution to global pollution by these pesticides. The official OGSNK/GSN data ranks sea/ocean/lake basins in the following order based upon the amounts of total OCPs received from agricultural use: Eastern Arctic>Western Arctic>Pacific>Baltic>Caspian>Azov/Black>Baikal. A similar ranking was obtained using an independent set of data: Eastern Arctic>Pacific>Caspian>Western Arctic>Baltic>Azov/Black. In terms of riverine flow-associated discharge of HCH isomers (i.e., sum of alpha-, beta- and gamma-HCH) estuaries of the Kara, Okhotsk and Beloye (White)/Barents seas received more pesticides than other seas. No HCH was discharged to estuaries of the Eastern Siberian and Bering seas. For DDT and its derivative (DDE), estuaries of the Kara, Caspian, Okhotsk and Baltic seas received the greatest amounts. During our study period (1988-1996), HCH transport was more prevalent in the majority of rivers reflecting both the official ban on the use of DDT in the former Soviet Union and the greater popularity of HCH as a pesticide. In general, it appears that Russian rivers play a significant role in OCP contamination of some estuaries of regional seas, especially those of the eastern Arctic basin, such as the Kara Sea.

Invasion history, distribution, and relative abundances of Dreissena bugensis in the old world: a synthesis of data

We examined trends in expansion patterns and relative abundances of Dreissenabugensis in reservoirs and major river systems in eastern Europe. Based on our own data and data from the literature, it is apparent that trends were variable across river basins and not easily related to environmental conditions. In some cases these did not conform to the patterns typically found for dreissenids. In the early period of expansion beyond its native range in the Dnieper-Bug delta and estuary, D. bugensis rapidly replaced Dreissena polymorpha in the upper Dnieper River system, but increased only gradually and over time became less abundant relative to D. polymorpha in the Don-Manych River system. Contrary to the Dnieper and Don River systems, in the Volga River system considerable spatial variability in relative abundances was apparent, particularly in northern reservoirs. Moreover, even though D. bugensis usually displaces D. polymorpha as the dominant dreissenid, the latter can remain dominant in certain types of habitats where conditions are less favourable for the former. Suggested factors that may be responsible for differences in invasion patterns in the river systems may include differential responses to temperature, or to some other factor(s) associated with geographical latitude, the level of water mineralization, and selective predation by molluscivorous fish. In particular, the northward expansion of D. bugensis seems to be limited by temperature. The lack of long-term data on appropriate scales precludes linking these differences to specific features within the environment, but our comparisons indicate that the expansion of D. bugensis relative to D. polymorpha is more complex than previously believed.

The State of knowledge about wetlands and their future under aspects of global climate change: the situation in Russia

About two-thirds of Russia’s land area are flat lands, which contributes to the development of conditions favouring wetland formation. Wetlands cover vast areas, especially in the north. Wetlands in the former Soviet Union were not recognized as separate or distinct ecosystems and this is still the situation in Russia today. Bogs are one of the most abundant and typical wetlands and were treated as worthless wastelands. Beginning in the 17th century and continuing under the Soviet government there was an enforced policy to drain wetlands and reclaim the land, mainly for farming. After the collapse of the USSR, this practice was discontinued along with the Soviet model of agriculture and an end to the forced and unnecessary use of pesticides and fertilizers with the result that the toxic load on Russian aquatic systems decreased drastically. Industrial production was also greatly curtailed. While it is now recovering, many of these are turning to environmentally-friendly technologies. The intensity of land-use related impacts upon Russian wetlands is negligible compared to that in more densely populated countries and therefore the environmental conservation of wetlands in Russia may not currently be an urgent problem. There is currently no consensus on what the overall direct and indirect impacts of climate change on the number of Russian wetlands will be—in some areas they may increase but decrease in others. In Russia, the most urgent issue is not the preservation of wetlands but the development of proper wetland management practices. For effective plans, data and information on wetland status, trends and characteristics are required that are not currently available.