The radiocaesium interception potential (RIP) at an agricultural site in Germany

Erosion and accumulation sites differ in the amount of fallout 137Cs due to its particulate translocation together with the soil. To examine whether these sites differ also in the radiocaesium interception potential (RIP) of the soil, the RIP of the plough horizon and the first layer of the B horizon was determined at 60 nodes of a 25 m x 25 m grid of a field in Scheyern, Germany, where erosion has been observed in earlier studies (e.g. J. Environ. Radioact. 53 (2001) 41). Upslope of the slope inflection point, the RIP values in the Ap and B horizons were significantly greater than downslope. Moreover, the RIP of the Ap horizon was positively correlated with the elevation a.s.l. of the points indicating an effect of erosion processes on the RIP. This assumption was supported by the soil morphology and the highly significant correlation of the RIP with soil erosion rates determined earlier by radiotracer quantification [Naturwissenschaften 89 (2002) 43] if four of 31 soil erosion points located close together were omitted. These results indicate that erosion not only modifies the pattern of fallout Cs but also the pattern of RIP.