ИСТИНА

It is known that the boreal wetlands play an important role in a global carbon cycle. In particular, they sequester the atmospheric carbon in peat deposits and release methane to the atmosphere. Since a general classification of boreal and sub-arctic wetlands in Siberia does not exist to date and only crude representation of the land cover is used as a base for global modeling, the real contribution of wetlands to the land-atmosphere interactions remains uncertain. We applied a multi-scale approach to make a general and realistic estimation of land cover in western Siberia (WS), which can be used in the models of ecosystem carbon dynamics and inventory of methane emission in wetlands. We produced a regional-scale inventory of the wetland area by digitizing a paper-based “Wetland typology map” (1:2,500,000), in which the entire area of WS is divided into 20 wetland types and complexes. The digitized map was further refined by manual classifications based on satellite imagery to provide more details on spatial structure of the patterned peatlands, which are widely distributed in the boreal region of WS. For this purpose, we chose five test sites of about 5000 to 7000 km2 according to the climatic gradient of distribution of the major wetland types. The satellite images with medium spatial resolution (LANDSAT TM, ETM+ from Global Land Cover Facility, glcf.umiacs.umd.edu/) were processed via the visual interpretation in the scale of 1:200,000. At this stage, the areas of the test sites were classified into 10 wetland classes, in contrast to previously prepared regional scale map that used only 3 classes within the boreal region.