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As a result of investigations authors discriminate the model series of transformation (evolution) of urban soils.The series depend on soil forming conditions especially on properties of parent material,ages,characteristics of land use and reflect the different stages of urban soils development in time.It was established that the most of urban soils and soil-like bodies are relatively yang on different parent substrate.These soil-like bodies are of initial stages of evolution characterizing by high velocity of biological and biochemical processes.Moreover,natural soils are transforming intensively in the cities.The soils/soil-like bodies of different age (from 5-10 to 300 and more years) and soil mesouphona of urban forests,parks,and residential zones of Moscow and Petrozavodsk (natural zone is south taiga)cities on different parent materials were investigated.The classification system for techno-transforming and urban soils by Stroganova and others (Stroganova et al.,1998,2000; Gerasimova,Stroganova et al.,2004) used.Three types of model series of urban soil evolution was distinguished:(i) natural soil — soils with light impact — strongly transformed specific urban soils Urbanozems (the agro-stage is possible); (ii) artificial soil-like constructions Thechnozems — Urbanozems; (iii) surface-transformed Agro-and Urbo-soils — natural soils (only in urban forests and forests parks).Natural forest soils are represented by Albeluvisols,Arenic Cambisols (in Moscow) and Podzols (in Petrozavodsk).The model series of second type are prevailing at Petrozavodsk.The diversty of Technozems and Urbanozems on toxic human-made and other technogenic sediments have been described.The intensity of technogenic transformation is lower in forest-park and parks than in residential areas.However,areas of human-transformed soils were found here.We described also human-transformed soils with complicated profile with horizons of different genesis (agro-,urbo-,techno-).These horizons reflected the history and character of human impacts on the plots.Chemical and physical properties of these soils are corresponds to those studied previously and reported on SUITMA 2000,SUITMA 2003 (Prokofieva,Stroganova et al.).Successions of soil biota taking place in transforming urban soils impact some trends of soil properties transformation.Mesouphona investigation showing the changes in its structure at different succession stage according the model series.Preliminary results:(i) dominance and abundance of Urbanozems mesouphona complex for modern settlements are not corresponding with ones of different natural soils; (ii) the stages of mesouphona successions are corresponding with stages of model series; (iii) structure of mesouphona complex essentially depends on the presence of mesouphona source and toxity of parent material on the plots of early formation stages; (iv) unlike the Urbanozems of modern settlements,the old urbanozems of rural settlement (described in city parks and forest-parks) have some peculiarities in mezofauna complex structure.