Особенности генезиса и стратиграфии торфяной залежи болота Ельня

The results of investigation of the genesis and stratigraphy of a peat deposit of the Yelnya bog carried out in five cross sections in the conditions of the Republic of Belarus are presented. The genesis of the Yelnya bog is due to the activity of the Poozerie glacier in the territory of the Polotsk aqua-eoglacial lowland surrounded by glacial hills, which was responsible for some special features in the peatland formation and structure. The Yelnya bog belongs to a group of interfluvial peat deposits that occur in valleys underlain by thick clay strata. This peatland is of Baltic type with an uplifted central part. There are two areas having their own tops of uplifts. In the territory о the Yelnya bog there are 36 lakes with more than 1 ha and 82 lakes with less than 0.5 ha. In part of lakes their bottom is bedded with lake sediments of residual type. The origin of the other lakes having peat bottoms and coasts is connected with the peatland development. Five cross sections of the peat deposit were described with details given for the changes оf the peat type, its botanical composition, percent content and degree of decomposition with depth in 15 sampling points. The stratigraphic analysis of the Yelnya peat deposit in five cross sections suggests that it is mainly formed by sphagnum magellanicum and sphagnum fuscum peat its decomposition degree ranging within 10-35 %. It was shown that the modern surface relief does not depend on the topographic peculiarities of the mineral bed of a peat deposit, but is determined by differences in intensities of the bog vegetation growth and peat deposit accumulation, which are due to climatic and hydrogeomorphological conditions. In addition to these factors, the bottom relief features and the composition of underlying soils have a pronounced effect on the peat deposit structure and composition. Anthropogenic factors are of great importance for the present conditions of the bog. As a result of drainage of the peripheral bog areas, a part of the deposit with the damaged hydrological regime is often subject to the fire hazard, when peat deposits burns down to a considerable depth. To renew the peat generation processes some ecological rehabilitation measures are required in damaged areas, firstly consisting in the restoration of their hydrological regime