Application of Chernobyl-derived 137Cs for the assessment of soil redistribution within a cultivated field

Vast areas of Europe were contaminated by the Chernobyl-derived 137Cs in April–May 1986. This paper reports a detailed study of the post-fallout 137Cs redistribution within a 1 ha field located in the Chasovenkov Verh catchment in the northern part of the Middle-Russian upland. Particular attention was paid to the study of reference inventories. It is shown that the random spatial variability of 137Cs is similar within undisturbed and cultivated parts of a flat interfluve. Systematic spatial variability is not essential for a relatively short (200 m) topographical unit with simple relief. The analysis of a soil redistribution pattern within the study field using the Chernobyl 137Cs technique demonstrates that it is possible to identify areas of soil loss/gain. This pattern does not reflect soil redistribution for the whole field, because these have been only 12 years since the Chernobyl accident. Net erosion rates based on 137Cs method were comparable to soil losses directly measured at the study field.