[V.I.Vernadskiĭ's theory of the biosphere and modern problems of radioecology].

The importance of Vernadsky's scientific heritage for the present stage of science development was substantiated. His role in the formation of radioecology as an independent scientific discipline was emphasized. The ecological consequences of an anthropogenic increase of the radiation background and the prospects of nuclear energy development were considered.

[The change in efficiency of protective measures for reduction of 137Cs accumulation by agricultural plants in various periods after the Chernobyl accident].

Dynamics of 137Cs transfer factors to plants and the effects of protective measures on this radionuclide accumulation in the agricultural production is estimated on the example of the south-western regions of Bryansk District. Three periods in decreasing the 137Cs content in plants during 20 years after the Chernobyl accident are identified. The contribution of radionuclide decay, natural biogeochemical processes and protective measures aimed at reduction of the 137Cs accumulation in agricultural plants during various periods after radioactive fallout is shown.

[Methodology for an assessment of derived radiation levels for agrocenoses].

Radiation protection of agrarian ecosystems should be considered as an integral part of a system for radiation protection of environment, with a special concern to agroecosystems' features. A methodology is proposed for an assessment of maximum permissible doses of radiation impact for agrocenoses based on an unified analysis of available data about effects of radiation in cultivated plants. It is considered as a component of radiation protection system for agricultural ecosystems.

[Soil sorption and transfer from it to plant of the radioactive and stable isotopes of chemical elements: methodology and experimental approach].

The adsorption of pair nuclides 60Co/Co and 65Zn/Zn by solid phase and their availability to plants were studied in soil suspension conditions and in the sod podzolic soil under controlled moisture. The situation when the radionuclide in constant activity is entered to system (surface water, soil) with different heavy metal contamination has been modeled. Was observed that soil contamination with heavy metal Co (Zn) significantly reduce sorption of the radionuclide 60Co (65Zn) by solid phase.

[Radioecology as a branch of natural science: some thoughts on the interesting past, intricate and vital present and future prospects].

The paper describes more than a century-old history of radioecology, science which studies radionuclide migration in the environment and ionizing radiation effects on biota. The main stages are identified in the development of this branch of natural science associated with the study of problems of radioactive contamination of the biosphere (global radionuclide fallout after nuclear weapons tests, radiation accidents with the release of radioactive substances to the environment). Currently, the basic imperative of radioecological investigations is the analysis of radioecological aspects of nuclear power engineering (mainly problems of radioactive waste management).

[The cradle of the Russian radioecology (to the 50th anniversary of the Kyshtym radiation accident)].

On September 29, 1957, at a nuclear industry facility (Production Association "Mayak"), there was a large radiation accident resulting in the release of radioactive wastes into the environment and the formation of the East-Urals Radioactive Trail (EURT). Within the EURT and there established in 1958 an Experimental Scientific Research Station (ESRS) which came to be known as alma mater of domestic radioecology, various comprehensive long-term investigations had been carried out. The main results of these 50-year investigations have been summarized for a broad range of problems on radionuclide migration in the natural environment and ionizing radiation effects on biota, as well as problems of environmental protection.

[The radioecological situation in the agricultural sphere in the contaminated regions of russia during the long-term after the Chernobyl accident].

The results of the contamination monitoring of the agricultural land and products in 2000-2005 in the regions of Russia affected by the Chernobyl accident are presented. The contribution is assessed of foodstuffs to the formation of internal exposure doses to the population during the long-term after the accident. Prediction is made of the change in the radioecological situation in radioactively contaminated areas.

[Radiological assessment of protective countermeasures in the private sector of rural settlements in the Chernobyl nuclear power plant accident area].

The effectiveness of countermeasures on private farms in rural settlements of the Russian Federation affected by the Chernobyl accident for the period of 1986-2005 was assessed. The averted collective doses to the residents of these settlements and the contribution of restrictive and agricultural countermeasures to dose reduction in the rural population have been estimated.

[Chernobyl and the environment].

Analyzed information which describes a wide spectrum of the consequences of radioactive contamination of natural ecosystems by the Chernobyl accident. The main regularities of radionuclide migration in the environment was been considered and scales of radiation damage to biota assessed. The area where signs of direct damage to biota are visible is shown to be noticeably smaller in size that the area where radionuclide concentration in environmental objects is above the permissible levels.

[The effects of the agricultural countermeasures on the irradiation of the population in the areas affected by the Chernobyl nuclear accident].

Radiological results were evaluated from the introduction of protective agricultural measures in the collective sector of the agroindustrial complex in the Chernobyl affected areas for the period of 1987-2005. The averted collective doses due to the reduction of 137Cs concentration in farm products were estimated, including the contribution to the averted collective dose of different food stuffs consumption.

[The effects of non-human species irradiation after the Chernobyl nuclear accident].

Data are presented on the effects of irradiation of different biota species after the Chernobyl accident.

[The transfer of 90Sr and of 137Cs radionuclides in the chain of soil-fodder-animal products in the area contaminated as a consequence of the Chernobyl AES accident].

The database on 137Cs and or 90Sr transfer factors in the soil-fodder-animal products chain compiled in the framework of the project "Radioecological Consequences of the Chernobyl Accident" under the French-German Initiative was analyzed. The 137Cs transfer factors were determined into 10 fodder types for farm animals. The 137Cs and 90Sr transfer from daily diet to milk is practically independent from milk yield and season and is about 0.

[The use of computer system in the introduction of countermeasures in agriculture after the Chernobyl accident].

In the development of strategies for countermeasures aimed at the rehabilitation of contaminated areas, essential is to identify criteria for assessing their effectiveness and factors influencing the priority of the criteria chosen. A method is suggested for assessing effectiveness of countermeasures in agriculture based on a multicriterium analysis of radiologic, economic, regulatory and socio-psychological indicators characterizing the use of countermeasures. Rating of countermeasures strategies is presented depending on financing of works on the rehabilitation of the Chernobyl affected areas.

[Radiation protection of the environment: anthropocentric and eco-centric principles].

The second half of the XX century was dominated in the field of radiation protection of the environment by the anthropocentric concept stated by the International Commission on Radiological Protection (ICRP). According to this concept "if man is adequately protected by radiological standards then biota are also adequately protected". At the end of the XX--beginning of the XXI centuries in the area of area of radiation protection of nature an ecocentric strategy is beginning to develop where emphasis has swung to the protection of biota in their environment.

[Effectiveness of measures directing to lowering the dose of radiation to residents of rural settlements in the extended period after the accident at the Chernobyl atomic energy station].

Justification of the application of countermeasure options in the long term after the Chernobyl accident is presented exemplified by a number of rural settlements located in areas with different fallout density. Protective and rehabilitation countermeasures are ranked based on the criterion such as cost of 1 man.-Sv.