农田黑土有机质和速效氮磷不同尺度空间异质性分析

Analysis for Spatial Heterogeneity of Organic Matter Content and Available Nutrients in Blacksoil Crop Area with Different Scales

应用地统计学的方法并结合G IS空间分析技术,对海伦市农田黑土区域不同尺度的耕层土壤有机质和速效养分进行了空间异质性分析。结果表明,大尺度下土壤有机质和碱解氮半变量函数的最佳理论模型符合高斯模型,小尺度下有机质最佳理论模型为球状模型,碱解氮符合指数模型,2种尺度下速效磷均符合线性模型,速效磷变异系数较大。不同尺度下土壤养分表现的空间自相关的变化有很大不同,说明不同的生态学过程在不同的尺度下起作用。

Geostatistics combined with GIS was applied to treatment and analyze the spatial variability of soil nutrients in topsoil （0-20 cm） in blacksoil crop area with different scales. The results indicated that the semivariogram of organic matter content and available nitrogen were best described by Gaussian model in large scale;The semivariogram of OMC was fited by sphericity model; the AN was best fitted by exponential model in small scale; and available phosphorus was best fitted by linear model in both scales. CV of AP was changed bigest of all nutrents. The analysis also showed that the spatial auto-correlations of soil nutrients are very different in different scales, which indicated the change was impacted by different ecological process.