A comparison between simulated and measured data from five runoff plots established at RDCSEC Perieni, Romania for the period 1985-2005, was performed for the estimation of soil erosion and runoff rates under different conditions concerning vegetative cover. Plots were cultivated with different crops, viz., maize, beans, soyabeans, winter wheat and brome grass ( Bromus sp.). The estimates of erosion or deposition rate (t/ha per year) represented an average rate for the period extending back from the time of sampling to the start of Cs-137 fallout. The reference sites have been under continuous vegetation cover in the last 60 years and are situated on the line, which separates selected basins. Erosion rates varied depending on the crop rotation. Less eroded was the plot No.5 from which only 2.153 t/ha per year of soil was lost and it corresponds to a structure where crops offered a very good protection of soil against erosion. The most eroded was plot No. 2 that was cultivated most of the time with maize, bean and soyabean and, from which an amount of 8.995 t/ha per year of soil was eroded. The comparison between measured (based on historical registrations from the runoff plots since 1985) and simulated data by different models (proportional model, Mass Balance (MB) model1, MB2 and MB3) showed that models fitted for values of erosion which ranged between 4 and 7 t/ha per year. Beyond this range, simulated data were, generally, either underestimated (for E>7 t/ha per year) or overestimated (for E
