中文摘要：

开展土壤重金属空间变异规律的研究,有助于查明土壤重金属在区域空间内的变异原因、结果和趋势,揭示其空间分布规律,从而为土壤环境规划和管理提供科学依据。本文利用地统计学方法,对原阳县土壤重金属的空间变异规律进行了研究。研究表明：土壤Cu、Zn、As和Cr在东西向均无明显变异,Cu、Zn和As的变异趋势相近,在18 km范围以内各方向均无变异,主要受区域因素影响,在18 km范围以外,除东西向外均出现不同程度变异,受区域因素和非区域因素共同影响;而土壤重金属Cr仅在30 km以外南北向变异明显,说明土壤Cr主要受区域因素影响;土壤Zn、As和Cr元素的半方差函数最优拟合模型为指数模型,Cu元素则为球形,交叉验证结果表明模型和参数合理;从块金效应来看,Cu最为明显,说明Cu的空间变异性最大,受非区域因素影响显著,而Cr的空间变异性最小,主要受区域因素的影响;在此基础上,利用选定的模型和参数,采用ArcGIS 9.0软件Kriging插值法制作了土壤元素空间分布图,结果表明土壤各重金属的分布规律基本一致,高值区主要集中在西北角的小店镇附近以及南部的太平镇和原武镇附近,总体呈现南高北低,东西向变化不明显的特征,这可能与土壤的沉积成因与当地矿山污染有关。

英文摘要：

The study of the spatial variability of the heavy metal in the soil allows for investigating reasons,results and trends of the regional variability and revealing the spatial distribution characteristics which provide a scientific basis for soil environmental planning and management.In this paper,the geostatistics method is used to study the spatial variability of heavy metals in soil at Yuanyang County.The results show that Cu,Zn,As and Cr in the soil have no significant variability in the east-west direction.Cu,Zn and As almost have the similar variability trend;Cu,Zn and As almost have no variability in all directions within the scope of 18 km,which indicates that the spatial distributions of these metals are controlled by regional factors.But they have obviously variability beyond 18 km,which indicates that the spatial distributions of these metals are controlled by regional and non-regional factors.But Cr in soil has obvious variation only in the north-south direction beyond 30 km,indicating that its spatial distribution is mainly controlled by regional factors.The semivariogram models of Zn,As and Cr are exponential,and the model of Cu is spherical.From the nugget effect,Cu is quite obvious and Cr is the worst,which also indicates Cu is affected by the nor-regional factors insignificantly and Cr is mainly affected by the regional factors.Based on the selected model and parameters,Kriging interpolation method of ArcGIS9.0 is adopted to make the spatial distribution map of the elements.The results show that the distribution law of different heavy metals in the soil is basically the same,high-value areas are mainly in the north-west corner of Xiaodian town,as well as the southern town of Taiping and Yuanwu nearby.On the whole,the distribution characteristic of the heavy metals is high in south and low in north and its change is not obvious in the east-west,which may be related to the deposition conditions of the soil and the local mining-related pollution.