Mapping of Soils and Lands to Assess Their Condition
摘要
This article provides a brief overview of the soil mapping work carried out in the Baikal region. In a significant area of the studied territory, the structure of the soil cover is subject to the laws of mountain zonality. The height above sea level of the earth’s surface within, for example, Irkutsk oblast ranges from 300 to 2875 m; the climatic conditions of soil formation are contrasting, from wet and cold to very dry and warm. This paper presents one of the maps of agroecological zoning of soils of Irkutsk oblast compiled by the authors. Soil–agroecological zoning of a territory is a way of analyzing and displaying soil cover, taking into account the regional features of their development in various natural and climatic conditions due to a sufficiently large area of territory (elements of latitudinal zonality are observed on a leveled surface) and a wide variety of landforms. The legend of the map of agroecological zoning of soils contains names of soils in accordance with the new classification, soil-forming rocks, vegetation and their productivity, altitude above sea level, dryness index, the number of “active” temperatures, the period with negative soil temperature, the duration of the warm period, the spread of permafrost rocks, and suitability for agricultural use. Suitable and unsuitable districts have been identified for use in agriculture. Various types of economic activities are recommended. Maps of land use in 1980, 2013, and 2023 are also provided (using the example of the most developed part of the Cis-Baikal lands). Most of the region’s land (more than 70%) is under forest vegetation. The area of agricultural land is about 4% in the region and 20% in the Irkutsk-Cheremkhovskaya plain. The Irkutsk-Cheremkhovskaya plain with neighboring settled areas (which occupies 11% of the territory of the region, where the main part of the farmland is located) has relatively good natural and climatic conditions. With the collapse of collective farms and state farms since the 1990s, more than 50% of former agricultural land has been abandoned. A positive aspect of the “restructuring” of the state system is the emergence of a reserve of agricultural land for use in the form of abandoned land.