Comparison of the advantages and limitations of 137Cs, 210Pbex, and 7Be fallout radionuclides in soil erosion assessments

Fallout radionuclides, FRNs, (i.e., 137Cs, 210Pbex, and 7Be) are being increasingly used to obtain quantitative information on soil erosion and sediment redistribution within agricultural landscapes over different timescales. The technique is frequently regarded as a valuable complement to conventional measurement methods. The objective of the present article is two-fold: to review the advantages and limitations of each of the above three FRNs and to identify the key gaps in the current knowledge on their application. In addition, guidelines are introduced for selecting the most appropriate FRNs and the associated application methods for a wide range of spatial and temporal scales. Also, the key objectives to be pursued in future investigations including upscaling FRN applications in soil erosion to catchment scale and the shift from their use as a research tool to a decision support one will be explored.