以高密市为例,利用GIS和地统计学方法在县域的尺度上分析土壤有机质、全氮、碱解氮、有效磷、速效钾、有效锰、有效铜、有效锌、有效硼9种养分的空间变异情况,利用克里格插值分析土壤养分的空间分布格局。结果表明,有效磷变异系数最大为48.80%,有机质变异系数最小为21.76%,变异系数由大到小依次为有效磷〉有效锌〉速效钾〉有效铜〉有效硼〉有效锰〉碱解氮〉全氮〉有机质。各土壤养分都具有良好的半方差结构,除了有效锰符合线性模型以外,其他养分均符合指数模型。速效钾、有效铜、有效锌具有强烈的空间自相关性;有机质、全氮、碱解氮、有效磷、有效锰、有效硼具有中等强度的空间自相关性,自相关程度速效钾〉有效铜〉有效锌〉有效硼〉全氮〉碱解氮〉有机质〉有效磷〉有效锰。在空间自相关范围上,有效硼最大为28716 m,有效铜最小为1410 m。微量元素锰、硼在空间分布上呈现出明显的规律性,锰呈现出从北到南逐渐增加的趋势,而硼含量则是从北到南逐渐减小;有机质、全氮、碱解氮三种元素呈现出相似的空间分布格局;有效铜、有效锌没有明显的规律性;有效磷、速效钾高值区呈块状零星分布。该研究揭示了高密市土壤养分的空间分布规律,对于实施精准农业和耕地的可持续利用具有积极意义。
Geostatistics combining with GIS was applied to analyze the spatial variability and spatial distribution of soil nutrients in Gaomi at county scale,including 9 soil nutrients of SOM,AN(alkaline hydrolyzing nitrogen),TN,available K,available P,Mn,Cu,Zn and B.The results showed that the variation coefficient of soil nutrients followed the order of P Zn K Cu B Mn AN TN SOM.P had the highest variation coefficient of 48.80%,while SOM had the lowest of 21.76%.The semivariograms of soil nutrients were best described by exponential model,except for that of Mn,which was best fitted by liner model.K,Cu and Zn had significant spatial self-correlation,and other nutrients had medium spatial self-correlation.The spatial self-correlation degree ordered as K Cu Zn B TN AN B SOM P Mn.The spatial correlation range of B was the highest of 28716 meters,and that of available Cu was the lowest of 1410 meters.Mn and B showed an obvious regularity in spatial distribution,with the content of Mn increased gradually from north to south,while content of B decreased gradually from north to south in the study area.SOM,TN and alkali-hydrolysable nitrogen showed a similar spatial pattern,Cu and Zn had no significant geographical trends,and the high value areas of K and P spatial distributed sporadically.This study revealed the spatial distribution of soil nutrients in Gaomi,which had a positive significance for precision agriculture and sustainable use of land resource.