冶炼企业土壤重金属污染与pH分布特征分析

Analysis of Heavy Metal Contamination and pH Distribution Characteristics of Soil in Smelters

土壤p H值是土壤化学性质的综合反映,也是最能直观反映土壤污染变化且最易测得的参数。本文以某铅锡冶炼企业地块为例,通过对地块土壤进行调查,分析土壤重金属与p H分布特征。初步调查、详细调查阶段共布设159点位,采集样品1 049个。调查结果表明,地块超筛选值指标有铅、镉、砷、锌、锑、铊,其中砷在不同浓度段超标率均占比最大。pH多数为酸性及以下,部分出现强碱性的碱化现象。土壤pH与超筛选值重金属指标含量大致成正相关,随着p H的升高,重金属含量超筛选值占比增加,且浓度升高;不同重金属在土壤中的超筛选值占比排序为砷>镉>铅。本实例可为同类型地块土壤污染状况调查提供借鉴。

pH value of soil is a comprehensive refl ection of soil chemical properties,it is also the parameter which is the most easily measured and most directly refl ects the change of soil pollution.A lead-tin smelting enterprise was taken as an example in this paper.By investigation on soil contamination.it was analyzed the distribution characteristics of soil heavy metals and pH value.159 sites were arranged and 1049 samples were collected in the preliminary investigation and detailed investigation.The results showed that there were lead,cadmium,arsenic,zinc,antimony and thallium index exceeding risk screening values,and arsenic had highest proportion of diff erent concentration segments.Most of the soil pH value was acidic,some of the soil pH alkalization.Soil pH was positively correlated with the concentration of heavy metals index exceeding risk screening values.With the increase of pH value,the proportion and concentration of heavy metals exceeding risk screening values were increased.The proportion of diff erent heavy metals in soil was As>Cd>Pb.This example could provide reference for soil pollution investigation of the same type of plots.