The contribution of N.N. Rozov to the development of our knowledge about the geography and ecology of soils of the Soviet Union and the world is discussed. It is shown how the scientific discussions with participation of Rozov were gradually transformed into the contents of the Soil Map of the World (1975), and how the soil-bioclimatic approach toward mapping developed by Rozov was combined with the geochemical approach and realized in the map. A poorly known work on the soil-ecological regionalization of the world performed by Rozov and published in the Resources and Environment World Atlas in 1998 (12 years after Rozov's death) is analyzed. Up to now, this work remains an unsurpassed compendium of data on soil regimes.

The magnetic susceptibility of the upper soil horizons in the city of Moscow was studied by the itinerary, key, and transect methods. Statistical regularities were found for the magnetic susceptibility of soils developed under urban conditions. Kappametric measurements can be used for the rapid detection of technogenically contaminated soils on large (the whole city) and small (separate plots) areas of the territory studied. The delineation of areas on the basis of their magnetic susceptibility (minimum, maximum, and average values) was proposed for mapping contaminated territories.

A tentative grouping of technogenic soils is proposed, based on two groups of criteria: (a) type of human impact (mechanical or technical disturbance), chemical pollution, and the effect of the urban environment and functioning; and (b) sequence of horizons. The latter criterion is very close to that used in the new Russian soil classification system. Between soils or soillike bodies strongly changed by the above impacts and the natural soils, there are intergrades defined and named also in accordance with the new system. Hence, we have three sequences with three "central images" in each, for example: natural soil-techno-soil-technozem, where the techno-soil has some initial horizons (subsoil) identified, while the technozem is an artificial constructed soil with filled horizons.

Specific features of soil formation in urban botanical gardens are considered. Soils of botanical gardens differ from both urban and cultivated agricultural soils. The main trends in the development of soils in urban botanical gardens are the anthropogenic pedosedimentogenesis and homogenization of the layers deposited earlier. A new group of soils-recreazems-is proposed and substantiated. Recreazems are defined as reclaimed soils with many filled organomineral or peat containing (peat-compost and peat-sandy) fertile substrates.