[Review of Experience and Prospects of the Use .of Some Countermeasures Aimed at Decontamination of Various Ecosystem Types after the Chernobyl Fallout].

The review of our own and literature data on ecosystems decontamination problems after the Chernobyl ac- cident is presented. It has been shown that protective measures are effective in places with the highest radio- capacity of ecosystems, especially those which may enhance the value of factors of ecosystefi radiocapacity. The analysis of a number of possible effects of impact of pollutants on the biosphere and the consequences of the implementation of protective measures (countermeasures) is given. The system of rehabilitation of con- taminated territories and, above all, soils, is proposed. The history of accidents at nuclear plants knows many planned and implemented countermeasures (CM), which can be used with different efficiency to eliminate the consequences of accidents. A variety of CM was implemented during the Chernobyl accident and elimination of its consequences. The main objectives that underlie the choice of CM is desactivation of ecosystems, reduction of individual doses for workers and residents, reducing the collective doses to the population defined by their special reduction factor. The effect of the CM on the condition of ecosystems has virtually never been evaluated. A number of the implemented countermeasures, the mechanical removal of the top lay- er of soil contaminated with radionuclides (bulldozers, scrapers, graders) led to the complete destruction of ecosystems, which are then required to be consolidated, in particular, by creating forests. It seems important and necessary to carry out the analysis and classification of the main CM based on the theory and radioca- pacity.models in order to assess how the parameters affect the countermeasures of ecosystem radiocapacity and to identify optimal solutions for their application.