南京城市土壤pH和养分的空间分布

采用GIS与地统计学相结合的方法，对南京市城市表层土壤pH、全钾、全磷、速效磷、有机质和全氮的空间分布进行了研究。结果表明，南京市城市土壤pH、全钾的变异函数的理论模型均符合线性有基台模型，可以用克立格（Kriging）插值分析。全磷、速效磷、有机质和全氮经对数处理后，仍然没有合适的拟合模型，采用逆距离加权（IDW）插值进行了分析。土壤pH、全钾有较强的空间相关性，说明它们受成土母质和地形等影响较大，全磷、速效磷、有机质和全氮空间变异性很大，主要受城市人类活动及土地利用方式的影响。

Spatial Distribution of Soil pH and Nutrients in Urban Nanjing

Contents and distribution of soil pH,total potassium(TK),total nitrogen(TN),total phosphorus(TP),organic matter(OM) and available phosphorus(AP) across Nanjing urban area were studied using GIS technology and geostatistical analysis methods.Semivariograms for soil pH,total potassium(TK) were well fitted by linear with sill model,and could be further interpolated by block-Kriging,while no suitable model fitted the semivariograms for TP,AP,OM and TN,even after logarithm conversion of these properties.It was suggested that the spatial variability of pH and TK was primarily controlled by the structural factors of the spatial heterogeneity of parent material and landform,whereas variability of TP,AP,OM and TN was greatly affected by urban human activities and they were spatially heterogeneous even in a short distance.