The partitioning of natural radionuclides in a large alpine river

Abstract

In continuation of earlier radio-ecological studies, the results of specific investigations on the behavior of natural radionuclides ( 238U, 226Ra, 210Pb, 40K) in the freshwater environment of the Austrian part of the Danube River are presented. The investigations and interpretations of the results are carried out with regard to the partitioning of radionuclides in fresh water between the particulate and soluble phases. The underlying work is a mixture of radiometric analysis of in situ-samples of water, suspended matter and sediments of the fresh water environment of the Danube River, and grain size analysis. The affinities of the partitioning of the observed natural radionuclides to the artificial radionuclide 137Cs are shown. Specific attention is paid to the influence of non-radiometric parameters, such as, hydrological conditions (i.e., flow rate), solid particle concentration, and grain size distribution of suspended matter on the radionuclide partitioning and the dynamics of water/solid matter interactions. The results of this work can be used as a basis for investigations on special problems of fresh water radioecology (i.e., a more realistic parameter assessment for radio ecological fresh water models) in Alpine regions and for investigations of general environmental processes (i.e., distribution of atmospheric pollutants in a large river fresh water ecosystem; land erosion processes).