Migration of radiocaesium from bottom sediment to fish through benthic food chain

Abstract

For modeling radionuclide transfer from the highly contaminated bottom sediments to marineorganisms the dynamic food chain model BURN-POSEIDON has been extended with the addition ofbenthic marine organisms. The new model takes into account both pelagic and benthic marineorganisms grouped into a limited number of classes based on their trophic level and type of species. In detail, the model includes: phytoplankton, zooplankton, fish (two types: piscivorous and nonpiscivorous),crustaceans, and molluscs for the pelagic food chain deposit feeding invertebrates,demersal fish and bottom predators for the benthic food chain and coastal predators feeding by both pelagic and benthic organisms. Deposit feeding invertebrates consume organic part of bottom sediments with adsorbed radionuclides which then migrate through the food chain. All organisms take radionuclides directly from water as well as via food.The model prediction for activity concentrations of 137Cs in both pelagic and benthic organisms in the coastal area around the FDNPP agrees well with measurements.In addition, the transfer of 137Cs and several other radionuclides through food webs for the period1950-2020 have been modeled for the Baltic Sea.unt both pelagic and benthic marineorganisms grouped into a limited number of classes based on their trophic level and type of species. In detail, the model includes: phytoplankton, zooplankton, fish (two types: piscivorous and nonpiscivorous),crustaceans, and molluscs for the pelagic food chain deposit feeding invertebrates,demersal fish and bottom predators for the benthic food chain and coastal predators feeding by both pelagic and benthic organisms. Deposit feeding invertebrates consume organic part of bottom sediments with adsorbed radionuclides which then migrate through the food chain. All organisms take radionuclides directly from water as well as via food.The model prediction for activity concentrations of 137Cs in both pelagic and benthic organisms in the coastal area around the FDNPP agrees well with measurements.In addition, the transfer of 137Cs and several other radionuclides through food webs for the period1950-2020 have been modeled for the Baltic Sea.