复垦土地土壤有机碳空间插值方法研究——以平朔露天煤矿为例

摘要

It has important theoretical and practical value to monitor and evaluate reclaimed farmland by optimizing spatial interpolation to obtain the organic carbon content of reconstructed soil in mining area.To find out which is the best method for predicting the spatial distribution and variation of soil organic carbon in reclamation mining area,this study applied and compared multiple linear regression,inverse distance weighting method,ordinary kriging method and regression kriging in Pingshuo mining area.Prediction results were validated by Pearson' s correlation coefficient,RMS error,Root mean Square Error and Accuracy.Results showed that:① The spatial variation coefficient of soil organic carbon is high in reclaimed dumps of opencast coal mine,reaching up to 145.408％,which belongs to high level;② In terms of accuracy,the regression kriging is the best method,its Pearson' s Correlation coefficient reaches 0.984;RMS error,Root mean Square Error and Accuracy are-0.012,0.211,0.991 respectively.Multiple linear regression takes the second place;the effects of inverse distance weighting method and ordinary kriging method are the worst.③ According to the expressed details,regression kriging is more meticulous,which can also depict the beating and uncertainty tendency of the data;Inverse distance weighting method and ordinary kriging method have obvious smoothing effects,meaning the spatial variation is continuous.Regression kriging has obvious advantages to predict the content of organic carbon in the reclaimed dumps at opencast coal mine.%通过优化空间插值方法获取矿区重构土壤有机碳含量对于复垦农用地监测与评价具有重要的理论和实际应用价值.采用多元线性回归法、反距离加权法、普通克里金法及回归克里金法对平朔煤矿复垦区土壤有机碳含量进行空间插值分析,插值精度通过Pearson相关系数、均方根误差、平均预测误差以及准确度进行评价.研究结果表明:①露天煤矿排土场复垦土地土壤有机碳空间变异性较大,变异系数最高达到145.408％,属于强变异性;②预测精度上,回归克里金法的预测精度最高,Pearson相关系数达到0.984,均方根误差、平均预测误差以及准确度分别为-0.012,0.211,0.991,多元线性回归法的的预测精度次之,预测精度最差的为反距离加权法及普通克里金法;③局部细节表达上,回归克里金法的预测表达较为精细,能够较好地刻画出数据的跳动性和不确定性,反距离插值法与普通克里金法预测具有明显的平滑作用,空间变化较为连续.回归克里金法相较其他方法在露天煤矿排土场复垦土地土壤有机碳插值预测具有较大优势.