中文摘要：

以小流域为尺度，通过Kriging插值用Surfer8．0软件绘制南京邓下小流域土壤有机碳（SOC）和全氮（TN）等值线图。研究了土壤有机碳和全氮空间变异特征。结果表明：（1）研究区土壤有机碳和全氮平均值分别为1．60％和0．15％，变异系数分别为44．43％和30．73％，属于中等强度变异，有机碳的变异性较强。经Kolmogorov-Smirnov检验，土壤有机碳和全氮都符合正态分布。（2）选择球状模型、指数模型分别为土壤有机碳和全氮的半方差函数理论模型，土壤有机碳和全氮的C0／（C0＋C）值均小于25％，表明在变程内具有强烈的空间相关性；以小流域尺度进行土壤有机碳和全氮空间分布研究能得到较准确的结果。（3）研究区土壤有机碳和全氮分布规律是有机碳在北部较高，东南部较低，呈自北部向东南递减趋势，最低处以岛状分布在中南部，全氮空间分布和有机碳的空间分布趋势大致相同。

英文摘要：

The spatial variability characteristics of soil organic carbon （SOC） and total nitrogen （TN） were studied based on watershed scale, The data were analyzed by the Kriging interpolation method in the SUFER software. The results showed that the means of SOC and TN were 1.60 % and 0. 15 % , and the variance coefficients were 44.43 % and 30. 73 % respectively. Both of them belong to medium spatial variability. SOC and TN presented normal distribution with Kolmogorov-Smirnov test value 0. 123 and 0. 043. The theoretical semi-variogram models of SOC and TN were spherical and exponential respectively. The C0/（ C0 ＋ C） of SOC and TN were 24.12 % and 3.57 % respectively. It also indicated that the SOC and TN had strongly spatial self-relativity in this area. The geo-statistics precision of spatial variability of SOC and TN was significant based on watershed scale, with lag 0. 500 km and range 7. 408 3 km. The whole distribution tendency of SOC in this area was higher in the north part than that in the southeast part, but there was the lowest value existing in the middle part just as small block. The TN spatial distribution was similar with the distribution of SOC.