Geographic Information System to Monitor the Development of Negative Soil Processes in the Russian Federation.
Natalya V. Kalinina, Ludmila Kolesnikova, and Elena Birukova. V.V. Dokuchaev Soil Science Institute, Pyzhevskii per. 7, Moscow, Russia
Natural pedogenic processes do not always lead to increased bioproductivity. In its turn, human disturbance of natural pedogenic processes effects them ambiguously. Let us postulate that negative processes in soils are those which reduce the biological productivity of lands in general and particularly, that of crops. This postulate is questionable. For example, the erosion of serozems in the Middle Asia lead to the reduction of bioproductivity although these changes are evidently degradational, as degradation processes comprise all processes resulting in the thinning of soil profile and worsening of water-physical properties. As the compiled GeoInformational System (GIS) is that of soil processes, both types of processes are united. The GIS is based on the soil map of Russia with the scale of 1 : 2 500 000. The map contains approximately 26 000 mapping units and represents 205 soil types. As the map represents exclusively natural soils, it was complemented by the map of lands with the scale of 1 : 4 000 000. The emergence of new materials and methods in the last years arose the problem of map specification and complementation in order to make is compatible with new data such as the data of Remote Sensing (RS) and Digital Models of Relief (DMR). The problem of data convergence in the GIS is resolved with the help of georeferred topographical base with the scale of 1 : 1 000 000 and bringing all cartographic materials in correspondence with the topographical base. Basic layers of GIS include: (1) vectorial topographical base with the scale of 1 : 1 000 000; (2) digital model of relief created on the topographical base with the step of 300 m; (3) digital model of relief with the spatial resolution of 100 m; (4) high-resolution (30 m) Landsat spectrozonal space survey; (5) space survey with the resolution of 500 m and one-month temporal step; (6) vegetation index (NDVI) with the resolution of 250 m; (7) soil map with the scale of 1 : 2 500 000; (8) landscape map with the scale of 1 : 2 500 000; (9) land map with the scale of 1 : 4 000 000. On the basis of these maps, published data, and expert estimates, the following maps were produced: (1) soil erosion map of Russia, 1 : 2 500 000; (2) map of salinization of Russia's soils, 1 : 2 500 000; (3) map of chemistry of salinization of Russia's soils, 1 : 2 500 000; (4) map of solonetses, 1 : 2 500 000; (5) map of desertification of southern regions of Russia, 1 : 2 500 000; (6) schematic map of soil acidity; (7) map of humus status of Russia's soils. In the process of GIS development, the number of soil mapping units increased by the factor of 1.5. A unified approach made it possible to work out a unified database of soil properties. It is based on 205 soil types but differentiated by zonal allocation, granulometric composition, and type of land use. The database represents a broad specter of agrochemical and physical soil properties, by horizons. Negative soil processes proper are represented by the degree and depth of their manifestation for each mapping unit. Indirectly, the negative soil properties are included in the soil horizon database via the changes in the basic natural soil properties. The generation of computer version of soil map of Russia with the scale of 1 : 1 000 000 on the basis of archival author's copies, recognition of RS data, and DMR processing will make it possible to substantially renew and improve the contour part of maps. A significant defect of the present GIS is the absence of the map of dynamics of land use patterns for the period of 1990-2005, which excludes the problem of abandoned lands and the processes occurring there, including negative ones.