Differences in Inventories of Waterlogged Territories in Soil Surveys of Different Years and in Land Management Documents

摘要

On soil maps and in land management documents, the excessively moistened areas of the earth surface are shown differently, and their areas on three different source maps (large-scale soil survey map, land cadaster map, and land management planning map) may differ by five times. According to current land legislation, soil maps should be used for cadastral valuation and cadastral division of arable land. It is supposed that the three sources of information on the land cover do not contradict one another. We analyzed the allocation of waterlogged lands on these source maps in order to find the reason for the existing discrepancies in the areas of waterlogged lands. Soil and land management materials from four rounds of the soil survey in 1937-1996 and remote sensing materials from 1968 to 2018 were analyzed. It was found that, until the third round of soil surveys, the concept of waterlogged area was the same for soil scientists, cadastral specialists, and land surveyors and meant the areas of limited use for arable farming because of the excessive atmospheric or ground moistening. Since the mid-1980s, soil scientists have ceased to consider waterlogging as a factor limiting land use, whereas land management specialists have not changed their approaches. In the cadastral division of land, the use of soil maps has become fragmentary; often, land plots are characterized as agreed with the owner. In 1958, the area of waterlogged soils on the soil map of Tambov oblast was 14%; all these lands had certain limitations of their use for arable farming. On the soil map of 1986, the area of waterlogged soils reached 65%, though only 6% of them were of limited use for arable farming. Independent retrospective monitoring methods applied by us to this territory indicated that limitations in the arable use of land related to the soil water regime are observed on about 16% of the territory of Tambov oblast. It is suggested that the allocation of waterlogged soils and lands should be unified on the basis on the technology of retrospective monitoring of soil and land covers.