雄安新区土壤重金属地球化学监测关键问题探讨  

Discussion on Key Issues of Geochemical Monitoring of Soil Heavy Metal in Xiong’an New District

作　　者：郭志娟[1,2,3] 周亚龙 杨峥[1,2,3] 赵传冬[1,2,3] 成杭新 孔牧 彭敏[1,2,3] GUO Zhi-juan;ZHOU Ya-long;YANG Zheng;ZHAO Chuan-dong;CHENG Hang-xin;KONG Mu;PENG Min(Institute of Geophysical&Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang 065000,China;Research Center of Geochemical Survey and Assessment on Iand Quality,Chinma Geological Survey,L.angfang 065000,Chinma;Key Laboratory of Geochemical Cycling of Cartbon and Mercury in the Earth's Critical Zone,Chinese Academy of Ceological Seciences,Langfang 065000,China)

机构地区：[1]中国地质科学院地球物理地球化学勘查研究所,廊坊065000 [2]中国地质调查局土地质量地球化学调查评价研究中心,廊坊065000 [3]中国地质科学院地球表层碳-汞地球化学循环重点实验室,廊坊065000

出　　处：《环境科学》2020年第9期4169-4179,共11页Environmental Science

基　　金：中国地质调查局地调项目(DD20189123,DD20190527)。

摘　　要：为构建雄安新区土壤环境质量监控网,系统获取雄安新区建设前后土壤重金属地球化学数据,长期监测新区建设过程中土壤重金属的变化趋势,在分析雄安新区土地质量地球化学调查监测数据和土壤重金属元素地球化学空间变异特征的基础上,采用统计学方法估算构建新区土壤地球化学监测网所需要的采样密度、采样数量和采样周期等参数,为后续新区土壤重金属地球化学长期监测工作提供参考.结果表明,调查区重金属As、Cd、Cu、Hg和Pb元素变异系数>36%,属于高度变异元素;Cd、Cu和Pb元素块金系数均>75%,其高度富集是在较高自然背景上出现了人为源的叠加.在置信水平P为95%和90%时,对样本平均值允许误差Δ分别为5%、10%和15%的条件下,同时对新区土壤中8种重金属As、Cd、Cr、Cu、Hg、Ni、Pb和Zn进行土壤环境质量监测,最少合理采样数分别为1077个、270个、120个和767个、192个、86个.土壤各重金属元素可监测最小变化量(MDC)介于0.0025~2.54 mg·kg^-1之间.在不同的重金属年变化速率下土壤重金属监测所需要的重访间隔时间不同,在目前调查区重金属年变化速率条件下,调查区土壤监测所需要的重访间隔时间在2 a左右.To build a soil environmental quality monitoring network and collect the systematic soil geochemical data of heavy metals before and after the construction of Xiong’an New District(XND),long-term variations in soil heavy metal levels during the XND construction were monitored based on the land quality geochemical survey monitoring data and the geochemical distribution of heavy metals.Parameters such as sampling density,sampling quantity,and sampling period were estimated to construct the geochemical monitoring network,which provides a reference for the future long-term monitoring of soil heavy metal geochemistry in XND.The results indicate that variations in the amount of heavy metals As,Cd,Cu,Hg,and Pb are greater than 36%,while the nugget coefficients of Cd,Cu,and Pb are greater than 75%because of the superposition of manmade sources on the high natural background levels.At the 95%and 90%confidence levels,while the allowable errorΔof the sample mean value is 5%,10%,and 15%and heavy metals as As,Cd,Cu,Hg,Ni,Pb and Zn is monitored in soil environmental quality monitoring network,the proper numbers in the study area are 1077,270,120 and 767,192,86,respectively.The minimum detectable change(MDC)of each heavy metal species is between 0.0025 and 2.54 mg·kg^-1.Soil heavy metal monitoring requires different revisit intervals under different annual change rates,but in the study area,revisit intervals of soil monitoring are approximately two years under the current conditions of constant annual change rates.

关 键 词：土壤监测 重金属 合理采样数 最小可监测变化量 雄安新区 

分 类 号：X53[环境科学与工程—环境工程]