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Examination of ancient cultural layers will increase our knowledge about ancient urbanization and improve our understanding of urban soils and the processes involved in their formation and development.What components of soil biota were involved in the urban activities in the past? What biological indexes could be used for the indication of ancient urban activities? What was the survival period of the modified biological properties in the soil? These are the questions that still remain to be answered.In our study we have investigated the cultural layers of medieval settlements (Ⅷ-XVI centuries A.D.) in boreal and submountain areas of the European part of Russia.The mycological properties of soils including the culture layers were examined in comparison with 1) analogous undisturbed zonal soil,2) analogous zonal soils,which include the buried humus horizons of the same ages as the culture layers,3) modern urban soils in the same climate zone.Soil respiration,fungal biomass,species diversity and composition of fungal assemblages were determined to be used as biological indexes.The CO2 evaluation was performed by means of the SIR method.The fungal biomass and biomass structure were evaluated by using luminescent microscopy with Calcofluor white.The isolation and enumeration of microfungi were done by serial dilutions of soil samples on the solid media.The identification of unsporulated strains was performed by molecular genetic analysis of ITS regions of rDNA.To isolate microfungi of some trophic groups (utilizing keratin,cellulose) the 《bite》 technique was applied.The study has revealed that the investigated cultural layers and modern urban soils have rather similar mycological properties,as compared to the horizons of undisturbed zonal soils.The similarities of the culture layers and modem urban horizons have been demonstrated by a larger ratio of fungal spores in fungal biomass,higher species diversity of microscopic fungi,different species composition,mosaic distribution of fungal populations in urban horizons,a bigger proportion of everytophic species,increased occurrence of some ecological and trophic fungal groups.Although some total biological indexes of the cultural layers,e.g.,soil respiration,were comparable with those in buried humus horizons,the mycological properties of the cultural layers were substantially different.Buried humus horizons are usually characterized by poorer microfungal diversity and distinct genera and species composition.The mycological properties have revealed,that culture layers can be considered to be a record of urban human activities of the past.For example,the highest occurrence of health risk fungi (keratinophylic,potentially pathogenic) was noted in places of domestic waste and floors of dwelling houses.In other words,it is most obvious on the sites,where the keratin containing substrata could easily accumulate.This work was partly supported by grant N 05-04-48380a from the Russian Foundation for Basic Research.