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在俄克拉何马调查了坡度为12%和2～4%的皆伐林地,应用铯——137估算了土壤流失量.铯—137是一种大气核试验放射性沉降物.它能紧紧吸附在土壤颗粒上,因而可示踪土壤的移动.土样分析表明,皆伐、整地和造林没有引起坡度为12%的Carnasaw石质砂壤土的明显流失.测得的2～4%坡度的Sobol粘壤土的少量损失,是由于放牧使土壤紧实,覆盖减少,增大了地表径流所致.依据文献有关铯—137的损失量与土壤流失量的对应关系,估计该区土壤流失量为0.2t/ha·年.估计的土壤流失量大大低于6.7t/ha·年的允许土壤流失量.应用这种方法能估算各种条件下的土壤侵蚀量,但还需要更多的与土壤流失量和铯—137损失量有关的资料.
Soil erosion was estimated using cesium-137 in the Oklahoma survey of 12% and 2-4% slopes of the deciduous forest. Cesium-137 is a radioactive nuclear airborne sediment that adheres tightly Soil particles were thus tracked for soil movement, and soil samples showed no significant loss of Carnasaw stony sandy loam with a slope of 12% for clear cutting, site preparation and afforestation. Sobol A small amount of loss of clay loam is due to grazing so that the soil compaction, coverage reduced, increasing the surface runoff caused by the literature on the cesium -137 loss and soil loss corresponding to the relationship between the estimated soil loss in this area is 0.2 Estimated soil loss is much lower than the allowable soil loss of 6.7 t / ha · year. Using this method can estimate the amount of soil erosion under various conditions, but also requires more soil loss Volume and cesium -137 loss-related information.