Even a brief look at a geological map of Siberia will tell you that this huge natural region consists of heterogeneous rocks. In this connection each concrete region has its own natural geo-chemical background: in some of them an increased content of toxic substances in water is observed, in others vital elements are absent. A convincing example is the Katun river running through the mercury-rich province of Altai. It is a piece of good luck that no Katun reservoir has ever been built here as the level of this liquid metal in it would have been threatening.
A great number of technogenic anomalies along with natural ones have been recently observed in Siberia. Superhigh concentration of fluorine and beryllium is being detected near aluminum plants there. While burning in boiler houses high-ash coals that are mined in Eastern Siberia, soils and waters get contaminated by a number of radioactive and heavy metals. Nuclear weapons tests have also greatly affected the environment. Take, for example, tests on Semipalatinsk proving ground (Kazakhstan) that led to an increased content of a number of radioactive isotopes in Altai and even in Transbaikalia. And last but not least, a great harm is done to nature by mining mineral resources as well as by increasing volumes of chemical industry wastes.
All these problems were in the focus of research within the framework of the project "Geology and Geochemistry of the Siberian Environment". According to the director of A. Vinogradov Geochemistry Institute (SB RAS), Corresponding Member of RAS, Mikhail Kuzmin, researchers of the Siberian Branch of RAS, paid great attention to the study of mercury-contaminated Bratsk reservoir by chemical complexes situated on its banks. Here mercury levels in natural precipitation and in fish exceeds all permissible norms. Scientists of the region gave recommendations to the Irkutsk Region Administration concerning modernization of the industry and control of capture and consumption of fish, which are already applied in life. Mercury concentration has already been studied in Irkutsk and Novosibirsk reservoirs. It has appeared that in the former it is minimal, while in the latter it is less than in Bratsk but somewhat higher than in Irkutsk.
Technogenic processes taking place in rock terraces were studied in relation of sulfide deposits. A number of heavy metals (copper, cadmium, zinc, iron, etc.) can accumulate in settling lakes near deposits and later get into ground waters.
Data on geochemical anomalies received within the framework of the project make scientists seek natural barriers capable, on the one hand, to help bury dangerous wastes, and on the other hand, to find microorganisms cleaning contaminated waters. In this connection experiments in special containers representing water columns shut off from surface to bottom were carried out in the Novosibirsk reservoir. It was verified what quantity of toxic substances placed in them could separate out water plankton (this is necessary for complete elimination of contamination).
Permanent link to this publication:
LVietnam LWorld Y G