Morphogenetic features of the soil cover structure in the Pritazovsky Arctic (West Siberia)

Abstract

The aim of the study. To give a morphogenetic characterization of the soil cover structure (SCS) of the Pritazovsky Arctic.

Location and time of the study. Soi geography and soil genesis studies were carried out in 2009–2011 in the southern tundra zone of West Siberia on the left-bank part of the Taz River, in its lower reaches. Laboratory work, including analyses, was carried out in 2010–2016.

Methods. A large-scale and detailed soil survey was conducted at two key sites with different landscapes. The developed soil maps were digitized in the QGIS package. The obtained digital data about the areas and perimeters of soil areas and soil combinations were converted into MS Excel, where their mathematical processing was done. When classifying soil combinations, the taxonomic system of V.M. Friedland was taken as a basis, as well as the quantitative indicators for the SCS morphogenetic analysis, the indicators also proposed by V.M. Friedland.

Results. The basis of the soil cover of the Pritazovsky Arctic consists of Gleysols and Сryosols, which occupy 90,9% of the area. As for the largest areas of these soils, they vary slightly in area and outer perimeter length, having a simple geometric structure. All elementary soil areas (ESA) and soil combinations belong to small and medium-sized areas (<30 ha). More than 90% of the ESA have very small size (<5 ha). The smallest elementary soil areas are occupied by Folic-Сryosols of polygonal roller bogs. Most of the soil areas (83%) of the studied territory have a rounded or elongated shape with slightly curved borders and a short outer perimeter, which determines their monolithic and poorly articulated structure (the coefficient of dissection <2,5). The main differentiating factors of the soil cover are cryogenesis, gley processes, and detritogenesis. In general, the Pritazovsky Arctic soil cover is characterized as monotonously heterogeneous for territories with broken relief and homogeneously monotonous for territories with flat relief.

Conclusions. The soil cover of the Pritazovsky Arctic territories with a broken relief is more classificationally contrasting and less geometrically complex compared with the soil cover of the territories with a flat relief. The latter has a very complex geometric structure due to the large number of very small ESA. A mosaic of small soil areas, i.e. the large number of ESA and soil combinations per unit area, strongly distinguishes the tundra soil cover from the soil cover of other bioclimatic zones of West Siberia.