中文摘要：

基于地形因子与土壤有机质的相关分析,选取相对高程和汇流动力指数作为辅助变量.以普通克里格（OK）作对照,比较地理加权回归克里格（GWRK）与回归克里格（RK）在土壤有机质空间插值及制图上的精度与效果.结果表明：土壤有机质含量与相对高程呈显著正相关,与汇流动力指数呈显著负相关;经半方差分析,土壤有机质及其插值残差具有强烈的空间自相关;对验证集中98个样点的精度加以分析,RK法插值结果的平均误差（ME）、平均绝对误差（MAE）、均方根误差（RMSE）较OK法分别降低39.2%、17.7%和20.6%,相对提高度（RI）为20.63,GWRK法插值结果的ME、MAE、RMSE较OK法分别降低60.6%、23.7%、27.6%,RI为59.79.与OK相比,考虑了辅助变量的RK和GWRK明显提高了插值精度;GWRK考虑了样点位置,成图效果更加精细,对土壤有机质的局部模拟效果优于RK.

英文摘要：

Relative elevation and stream power index were selected as auxiliary correlation analysis for mapping soil organic matter. Geographically weighted variables based on regression Kriging （GWRK） and regression Kriging （RK） were used for spatial interpolation of soil organic matter and compared with ordinary Kriging （OK）, which acts as a control. The results indicated that soil or- ganic matter was significantly positively correlated with relative elevation whilst it had a significantly negative correlation with stream power index. Semivariance analysis showed that both soil organic matter content and its residuals （including ordinary least square regression residual and GWR resi- dual） had strong spatial autocorrelation. Interpolation accuracies by different methods were esti- mated based on a data set of 98 validation samples. Results showed that the mean error （ ME ）, mean absolute error （MAE） and root mean square error （RMSE） of RK were respectively 39.2%, 17.7% and 20.6% lower than the corresponding values of OK, with a relative improvement （RI） of 20.63. GWRK showed a similar tendency, having its ME, MAE and RMSE to be respectively 60.6%, 23.7% and 27.6% lower than those of OK, with a RI of 59.79. Therefore, both RK and GWRK significantly improved the accuracy of OK interpolation of soil organic matter due to their in- corporation of auxiliary variables. In addition, GWRK performed obviously better than RK did in this study, and its improved performance should be attributed to the consideration of sample spatial locations.