Using fallout lead210 measurement to estimate soil erosion in three small catchments in Southern Italy

Soil erosion and associated off-site environmental impacts have attracted increasingattention in recent decades, and there is a growing need for reliable information on rates of soil loss.The potential for using 137Cs fallout to quantify rates and patterns of soil redistribution overmedium-term timescales (ca. 45 years) has been successfully demonstrated in a wide range ofenvironments around the world. The similar behaviour of fallout 210Pb in soils offers potential for itsuse as an alternative to 137Cs, in areas where 137Cs inventories are low or are complicated byadditional fallout from the Chernobyl accident. There have, however, to date been few attempts tovalidate the use of fallout 210Pb measurements for assessing erosion rates. This paper reports anattempt to explore the use of fallout 210Pb to estimate rates of water-induced soil erosion onuncultivated land. It focuses on three small forest/rangeland catchments located in Calabria,southern Italy, for which measurements of sediment output are available. Comparison of theestimates of net soil loss from the catchments derived from 210Pb measurements with the measuredsediment output, confirmed the validity of the 210Pb approach. The soil redistribution rates estimatedusing 210Pb measurements were also consistent with equivalent estimates obtained for the samestudy catchments using 137Cs measurements.