基于地统计学的樱桃园土壤重金属污染评价及来源解析

Evaluation on Heavy Metal Pollution and Analysis on Its Source of Cherry Orchard Soil Based on Geostatistics

为研究天水市樱桃园土壤重金属污染的空间分布特征,实地采集0~20 cm土壤样品,测定重金属Pb、Cd、Cr、Cu、Zn含量,并运用多元统计分析等方法定量分析了研究区土壤表层重金属污染程度。结果表明:以甘肃省土壤背景值作为评价标准,除Cd元素外,其他元素的均值都超过了甘肃省土壤背景值;从土壤重金属元素空间分布格局来看,研究区东北部土壤重金属污染较西南部严重;从土壤重金属元素污染源来看,造成樱桃园土壤重金属污染最主要的因素为成土母质、农药;5种重金属元素均存在不同来源的污染,污染来源不单一,属于混合源污染。

In order to study the spatial distribution characteristics of soil heavy metal pollution sources of cherry orchards in Tianshui City,the paper collected 0 ～ 20 cm soil samples in the fields,determined the heavy metal contents of Pb,Cd,Cr,Cu and Zn and quantitatively analyzed the degree of heavy metal pollutions of the top soil of the studied area by using multivariate statistical analysis. The outcomes show that a) taking the background value of Gansu Province as the evaluation standard,it finds out that the average value of all elements exceed the soil background value of the province except Cd element; b) viewing from the spatial distribution pattern of soil heavy metals,the heavy metal pollution of the northeast of the studied area is more serious than that of the southwest; c) viewing from the pollution sources of soil heavy metal elements,the main factors that causing soil heavy metal pollution of cherry orchard are soil parent material,pesticide and; d) 5 heavy metal elements all have different sources and the sources of pollution are not single,belonging to mixed source pollution.