ECOMOD - An ecological approach to radioecological modelling

A unified methodology is proposed to simulate the dynamic processes of radi onuclide migration in aquatic food chains in parallel with their stable ana logue elements. The distinguishing feature of the unified radioecological/e cological approach is the description of radionuclide migration along with dynamic equations for the ecosystem. The ability of the methodology to pred ict the results of radioecological experiments is demonstrated by an exampl e of radionuclide (iron group) accumulation by a laboratory culture of the algae Platylmonas viridis. Based on the unified methodology, the "ECOMOD" radioecological model was de veloped to simulate dynamic radioecological processes in aquatic ecosystems . It comprises three basic modules, which are operated as a set of inter-re lated programs. The "ECOSYSTEM" module solves non-linear ecological equatio ns, describing the biomass dynamics of essential ecosystem components. The "RADIONUCLIDE DISTRIBUTION" module calculates the radionuclide distribution in abiotic and biotic components of the aquatic ecosystem. The "DOSE ASSES SMENT" module calculates doses to aquatic biota and doses to man from aquat ic food chains. The application of the ECOMOD model to reconstruct the radi onuclide distribution in the Chernobyl Cooling Pond ecosystem in the early period after the accident shows good agreement with observations. (C) 2000 Elsevier Science Ltd. All rights reserved.