EURO-ECO 2007 Hanover 4 - 5 December 2007	Environmental and Engineering Aspects for sustainable living
	European Academy of Natural Sciences, Hanover European Scientific Society, Hanover Russian Academy of Natural Sciences, Moscow

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Deflation processes, being uncharacteristic of the North territories, nevertheless are widespread in taiga and tundra zones of Russia. Aeolation-shaped atmogenic landforms are found in the basins of the rivers Nadym, Pyakupur, Ajvasedapur, Agan, Vakh and on high watersheds of the Tyumen region. In many respects, deflation focuses coincide with areas of intensive petroleum production and gas-extraction that has become more intense within last ten years.

The research objective is estimation of deflation progress in the reclaimed areas of the Tyumen region (North) in comparison with the deflation dynamics in natural conditions.

The research territory includes two districts:

• The middle course of the Nadym River (where no oil-fields exist, while deflation processes are widespread) (District 1);

• The middle course of the Pyakupur River on the Purovskaya Lowland and the Siberian Ridges border (where large-scale reclamation depends on the development of the Sutorminskoe field) (District 2).

The work is based on the facts collected during three-year field works in this territory (2004-2006) and decoding of remote sensing data (Landsat-5, 1988; Landsat-7, 2001; SPOT-4, 2006).

Obtained results allow recognize every district’s several special features:

• The District 1 sand deposits are located in three typical sites: the terrace complex of the Nadym River, terraces of the first and second order tributaries as well as high water-parting spaces;

• Every site is characterized by reduction of wind-blown sand square (by 11.5% on average, by 5-8% in large hollows);

• The District 2 sand deposits, besides natural wind-blown hollows, embrace 3 anthropogenic forms: line-transport, pit-run, oil and gas production forms;

• The total area of natural wind-blown hollows has grown steeply over past 30 years (19.57 sq km to 31.51 sq km). At the same time, positive dynamics is typical to the hollows to a greater or lesser extent involved in economic activity (sand recovery, road laying, power lines, etc.);

• The greatest danger to the territory is posed by sand pits. Large spaces and lack of soil revegetation activity make sand pits the cores of atmogenic processes activation;

• Detailed geodetic survey of a model wind-blown hollow over past 3 years indicated its expansion from 12.5 hectares to 13.8 hectares. The expansion is taking place near roads and in the line of prevailing winds.

On the whole, we can speak about a balanced state and preservation of bare sand areas in natural conditions. Simultaneously, the main deflation-stimulating factor is man’s impact (uncontrolled violation of soil-vegetable covering and minimum volume of soil regeneration works). In appropriate lithologic and geobotanical conditions, sand outcrops emerge even with a low anthropogenic impact on the environment. Atmogenic landforms are emerging in regions where they have not been observed earlier.

Consequently, deforestation and desertification produced by economic activity intensification is gradually increasing. This process is becoming the most serious ecologic problem in the North taiga and it claims greater attention and comprehensive study.