关中平原区土壤5种微量元素的空间变异及分布评价

为了揭示黄土高原地区农田土壤微量元素空间变异规律及分布特征,选择陕西省扶风县揉谷乡新集村为试验区,在219 hm2耕地上用网格法采集364个耕层(0~20 cm)土壤样品,对其5种微量元素B、Fe、Mn、Zn和Cu有效含量的空间变异进行地统计学分析,并结合Kriging插值结果对其不同级别含量的分布状况进行评价。结果表明,土壤有效B、Fe、Mn、Zn和Cu的理论半方差模型分别符合线性、指数、球状、指数和线性模型,有效B和Mn具有中等的空间相关性,有效Cu、Fe和Zn具有强烈的空间相关性;5种微量元素最大相关距离依次为:B、Cu>Zn>Mn>Fe,最大相关距离为648~1 855.1 m;5种微量元素表现出条带状和斑块状空间分布;有效Fe、Mn、Zn和Cu的含量分布与土壤水分有关,有效B的分布与土壤酸碱度有关。

Spatial variability and distribution of five soil micro-elements content in farmland of Guanzhong Plain

The paper is presented on spatial variability and distribution of 5 soil micro-element contents(available B,Fe,Mn,Zn,and Cu) in farmland of Guanzhong Plain.Total 364 top-layer(0-20 cm) soil samples were taken by grid from 219 hm2 farmland in Xinji village of Shaanxi Province and analyzed by Geotatistics method.Results indicated that the variogram of 5 micro-element nutrients showed a linear model(B),exponential model(Fe),spherical model(Mn),exponential model(Zn) and linear model(Cu).B and Mn had intermediate spatial correlation ranges,while Cu,Fe and Zn had sharp spatial correlation ranges.The order of longest correlation range in 5 micro-elements was B,Cu>Zn>Mn>Fe(from 648m to 1855.1 m).By using kriging method,the spatial distributions of 5 soil micro-element took on piece and speckle shape in study area,the spatial distributions of Fe,Mn,Zn,and Cu were connected with the moisture level,while available B was connected with the soil pH.