红壤侵蚀沉积点^137Cs垂直剖面分布特征

研究了红壤农田和荒地侵蚀沉积点中 1 3 7Cs的剖面分布特征 ,结果表明 ,沉积点在 1 7cm处有明显的峰谷 ,农田沉积点 1 3 7Cs含量要高于荒地 ;经估算 ,两沉积点的沉积速率相近 ,1 96 3年以来为 1 .0 3 cm/ a,近 2 0年约为 0 .74cm/ a;沉积点的 1 3 7Cs分布显示该区域侵蚀有减小的趋势 ;1 3 7Cs活度与有机质存在较好的相关性 ;1 3 7Cs在侵蚀研究中具有重要意义

Distribution Characteristics of 137Cs in Erosion Sediment in Red Soil Region

The distributions of 137 Cs in the profile of sedimentation points from cultivated and uncultivated region in red soil were analyzed and described. Results showed that there was a turning point at about 17cm in both profiles. The inventory of 137 Cs in cultivated sediment was higher than that of uncultivated. The sedimentation rate of both sediment points was about 1.03 cm/a from 1963 according to the position of peak. But it was about 0.74 cm/a in recent two decades according to 137 Cs distribution. The result also suggested that the erosion rate became smaller in recent years. There was a good relationship between organic matter and 137 Cs. It could be inferred that the distribution of 137 Cs in erosion sediment may be used as an effective measure to assess the work of water and soil conservation.