Permafrost-affected former agricultural soils of the Salekhard city (Central part of Yamal region)

Abstract

Soil cover transformation in Russian Arctic is considered as underinvestigated. In 1920s it was started systematical studying and exploitation of natural resources of Far North of Russia. Due to development of industry and growth in area population necessity in agricultural products was growing intensively and arable soils became typical component of the soil cover in polar cities surroundings. Nowadays, however, almost all the former cultivation fields are abandoned or in poor use. Abandoned agricultural soil in sub urban territories of the Salekhard city were studied with aim to evaluate alteration of soil morphology and chemistry under agricultural impact and clarify the specificity of this process in case of permafrost-affected soils. The predominance of sandy textured parent materials within Salekhard city area was one of the main reason of favorable agricultural using of land in the north of Western Siberia in previous years. Data obtained revealed that studied soils are characterized by properties caused both by former (or existing) anthropogenic influence and natural processes (e.g. cryogenic mass transfer). Soil organic carbon content depends mainly on the character of current land use and varies significantly in studied soils. Most of the soil samples showed the highest levels of soil nutrients in the topsoil. Former arable horizon is stable in time in terms of morphological features and agrochemical state. In spite of high level of soil acidity, content of nutrients in antropogenically affected topsoils is still high after 20 years of abandoned state of soils. This indicates that agrosoils with relatively high fertility of arable topsoils could exist during long time in case of sandy-textured parent materials.