基于ArcGIS地统计分析模块的土壤养分空间变异分析——以云南省建水县为例

Spatial Variability of Soil Nutrients Based on ArcGIS Geostatistical Analyst A Case Study in Jianshui County of Yunnan Province

基于GIS与地统计学原理,使用ArcGIS地统计分析模块研究了云南省建水县土壤碱解氮、有效磷、速效钾、有机质的空间变异情况。结果表明:4种养分的变异系数在48%~82%之间,有效磷变异系数最大为82%;碱解氮、有机质的变异函数最佳理论模型为高斯模型,有效磷、速效钾的变异函数最佳理论模型为指数模型;碱解氮、有效磷的块金系数介于42%~88.7%之间;碱解氮、有效磷具有中等空间相关性,受结构性因素和随机性因素共同作用;速效钾、有机质空间相关性较弱,受随机因素影响较大;4种养分的变程介于3548.9 m^7584 m之间。采用克里格插值方法进行最优内插,绘制了养分含量分布图,可更直观地了解县域的土壤养分丰缺状况。

By the method of geostatistics combined with GIS,the spatial variability of soil nutrients in Jianshui County of Yunnan Province,such as available nitrogen（AN）,organic matter（OM）,available phosphorus（AP）,available potassium（AK） and organic matter（OM）,were analyzed with ArcGIS geostatistical analyst.Results showed that the variation coefficients of four kinds of soil nutrients ranged from 48% to 82%,and the variation coefficient of AP was largest.Gaussian was the best variation function model to predict AN and OM contents,while exponential model was the best for AP and AK.The Nugget/Sill of AN,AP,AK and OM ranged from 42% to 88.7%.AN and AP presented a moderate spatial dependence.AK and OM presented weak spatial dependence.The ranges of four soil nutrients ranged from 3548.9 m to 7584 m.It was more directly to understand the soil nutrients status of Jianshui County with distribution maps of the nutrients content which were drew by the best interpolation of kriging method.