Problems of Using Digitized Thematic Maps on the Territory of the Former Soviet Union upon the Creation of the Soils of Russia Geographic Information System

Soviet and Russian pedologists, ecologists, geobotanists, geographers, and other specialists created a large set of maps on the territory of the former Soviet Union. In most cases, these maps were published; at present, they are available as hardcopies. Their digitization clearly shows various merits and demerits of thematic maps on the territory of the Soviet Union and Russia. A 20-year experience of the Laboratory of Soil Informatics at the Dokuchaev Soil Science Institute on the creation of digitized maps integrated into the Soils of Russia geographic information system (GIS) is discussed. The major stages of this work and the technology developed to solve the problems appearing during it are described. The reasons for certain difficulties in matching cartographic information contained on the maps of different and similar scales, the problems of georeferencing of the maps, and the problems related to the use of remote sensing materials and digital elevation models are discussed. The necessity of creating a unified cartographic base for thematic maps included in the GIS Soils of Russia [28] and the technology for its development are characterized. The distortions on the original topographic maps are corrected with the use of locally affine transformation functions realized in the GeoDraw-GeoGraph software package. The requirements for the quality of the maps-their suitability for georeferencing, topological correctness, and compatibility of different versions-are formulated. The problems of digital soil mapping upon the use of object-oriented GIS are elucidated. The Soil Map of the Russian Federation (1 : 2.5 M scale) was initially digitized in 1997. Since that time, four digital versions of this map have been created to reduce the initial errors and inconsistencies. It is argued that the fifth and sixth versions of this map should be created with allowance for the accumulated experience. DOI: 10.1134/S1064229311090110