Use of 7Be and 137Cs measurements to document short‐ and medium‐term rates of water‐induced soil erosion on agricultural land

Although 137Cs measurements have now been employed for assessing medium‐term (∼45 years) rates of soil redistribution on cultivated land in many areas of the world, the potential of 7Be as a sediment tracer in soil erosion investigations has largely been neglected. Because of its much shorter half‐life, 7Be measurements should provide a basis for documenting short‐term (or event based) rates of soil loss. This paper presents some preliminary results from a detailed investigation of erosion and sediment delivery within a 6.7 ha cultivated field in Devon, England, using both 137Cs and 7Be. Measurements of both radionuclides have been employed to derive estimates of medium‐ and short‐term rates of soil redistribution within the study field. The results obtained from the investigation confirm the potential for using 7Be measurements in soil erosion investigations, both in their own right and in conjunction with 137Cs measurements.