Soil maps of cities for the unified digital model of the soil cover of Russia

The soil cover of cities and towns within their administrative boundaries is composed of soils, more or less modified by the urban environment along with native, agricultural soils and non-soils. For preserving this diversity when introducing these new objects to the unified digital model of the soil cover of Russia, soil maps of 10 “test” cities have been compiled. The cities are located in several natural zones, and are intermediate in terms of their population. Mapping was performed by means of detailed purposeful deciphering, data on mapping units on the original soil map, and recent systematics of urban soils and their dependence on the urban environment. The approaches applied were supported by the experience in soil mapping of St-Petersburg, Moscow, Volgograd and few other cities. Soils were qualified in the system of Russian soil classification, and their areas, along with those of non-soils, were regarded as units in the theory of soil cover patterns. In all cities investigated, soil associations comprised urban soils per se, transitional soils including agro-soils and conventionally native ones; their ratios in the soil cover depend on both historical-socio-economical reasons and the natural enviroment.