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The loss of fertile topsoil is one of the principal soil degradation problems in agricultural landscapes worldwide. Mediterranean agroecosystems are particularly threatened to soil degradation because of the climate, a higher sensitivity to soil erosion and the intensification of human activities and agricultural practices during centuries. The severity of this problem and the expected increasing risk of soil erosion in Mediterranean cultivated landscapes as a consequence of climate change have generated a demand for estimations of soil redistribution rates and soil loss monitoring. In this study, a representative cultivated field of mountain Mediterranean agroecosystems was selected to estimate 137 Cs derived soil redistribution rates using a 137 Cs mass balance model. Besides numeric simulation was performed using the WATEM/SEDEM model to estimate spatially-distributed soil redistribution rates. A detailed topographic survey was done to obtain a high-resolution digital elevation model (2.5 m) of the study field and 137 Cs derived soil redistribution rates were used to calibrate the model. In the study field, soil erosion predominated over soil deposition. Mean values of 137 Cs derived soil erosion and deposition rates were 19.7 Mg h