沈阳市郊耕地土壤交换性锰含量的空间变异性

SPATIAL VARIABILITY OF EXCHANGEABLE MANGANESE CONTENT IN CULTIVATED SOILS OF SHENYANG SUBURBS

利用地统计学和地理信息系统相结合的方法研究了沈阳市郊耕地1994个样本0～20 cm耕层土壤交换性锰(Mn)含量的空间变异特征,编制了交换性Mn含量的空间分布图.结果表明:土壤交换性Mn含量基本符合正态分布,变异函数的最佳理论模型为球状模型,交换性Mn含量具有中等的空间相关性,空间自相关距离为12.42 km, 分维数D为1.69,由随机性因子引起的空间变异占36.6 %,由结构性因子引起的空间变异占63.4 %. Kriging内插图显示出交换性Mn的空间异质性主要受成土母质和土壤类型等结构性因子的影响.

The spatial variability of exchangeable manganese content in cultivated soils was investigated based on 1994 samples gathered from the 0~20cm surface horizon of farmland in Shenyang suburbs, Liaoning, China, and a spatial exchangeable manganese content distribution map was plotted by making use of the method of geostatistics in combination with the geographic information system. Results show that contents of exchangeable manganese fitted normal distribution, and its semivariogram a spherical model. The spatial dependence of exchangeable manganese content was moderate ranging around 12.42km witha fractal dimension D being 1.69. Random factors contributed to 36.6% of the spatial variability, while structural factors did 63.4%. The spatial heterogeneity of exchangeable manganese, showed by a Kriging interpolated map, was fundamentally influenced by structural factors such as parent materials and soil types.