^137Cs技术对长江三角洲丘陵区小流域土壤侵蚀初步估算

采集了长江三角洲丘陵区某一小流域的 8个土壤剖面共 2 6个样品 ,通过分析发现该小流域的土壤 1 37　Cs含量与采样深度之间具有比较良好的线性关系 (0 .98>R2 >0 .6 9) ;以坡顶作为参考点 ,提出该地区土壤中的 1 37Cs背景值约为 2 40 0 Bq/m2 ;建立了基于 1 37Cs技术的土壤侵蚀定量模型 ,并对该流域土壤侵蚀量进行了初步估算 ,结果表明侵蚀最严重的丘坡中部马尾松林地占总侵蚀量 38.2 3% ,坡麓的菜园土壤亦达 32 .89%。因而 ,对坡中和坡麓地貌部位采取相应的保护措施 ,可有效地防治水土流失带来的各种危害。

Primary Estimate on Soil Loss Amounts in Yangtse Delta Region Using ~(137)Cs Technique

The 26 soil samples in a small watershed of Yangtse delta region have been collected and its contents of 137 Cs have been determined. The results showed that the relationship between amounts of 137 Cs and depth of sampled soils is near linear (0.98>R 2>0.69). Based on the value of 137 Cs on the top of hill, we considered that 2 400 Bq/m 2 137 Cs is probably the background value in the region. Eventually, soil erosion and deposition was calculated,the amount of soil erosion on middle hill accounts for 38.23% of total erosion, and the value of vegatable soil occupy its 32.89%. Therefore, we should take some measures to provent the soil loss in this region.