摘要
为了评估宁夏石嘴山地区土壤—农作物系统中重金属的生态风险和健康风险,收集数据并分析了该地区土壤及玉米、水稻、小麦3种作物中重金属(Cd、Cr、Hg、As、Pb)的分布、富集特征及健康风险。结果表明,研究区土壤中重金属含量低于全国背景值,地累积指数显示土壤环境整体清洁;不同作物对重金属的富集能力表现出显著差异,小麦对Cd和Pb的富集能力较强,水稻对As和Hg的富集能力较强;此外,土壤pH与重金属的富集系数存在显著相关性,玉米对Cr和As的富集系数随pH升高显著增加,而水稻对As的富集系数随pH升高显著下降;土壤有机质通过降低重金属的生物有效性抑制了作物对重金属的吸收富集;在健康风险评价中,儿童通过手口摄入途径的非致癌风险指数较高,As的含量在部分样品中超出食品安全标准,需重点监测。本次研究成果为土壤污染治理和作物安全生产提供了科学依据。
This study analyzed the distributions,enrichment characteristics,and health risks of heavy metals(Cd,Cr,Hg,As,and Pb)in soil-crop(maize,rice,and wheat)systems in the Shizuishan area,Ningxia Hui Autonomous Region.The results indicate that the contents of heavy metals in the soils were below national background values,with the geoaccumulation index indicating an overall clean soil environment.Different crops showed significant differences in their ability to enrich heavy metals,with Cd and Pb being more enriched in wheat,and As and Hg being more enriched in rice.Moreover,significant correlations were observed between soil pH and heavy metal enrichment coefficients.With an increase in pH value,maize exhibited markedly increased enrichment coefficients for Cr and As,whereas rice manifested a notably decreased enrichment coefficient for As.Soil organic matter inhibited the ability of crops to absorb and enrich heavy metals by reducing the bioavailability of heavy metals.The health risk assessment reveals a high non-carcinogenic risk index for children via the hand-to-mouth route.The As content in some samples exceeded the limit specified in food safety standards,requiring targeted monitoring.The results of this study provide a scientific basis for soil contamination control and safe crop production.
作者
王志强
倪萍
张宏绪
石天池
杨建锋
张惠玲
WANG Zhi-Qiang;NI Ping;ZHANG Hong-Xu;SHI Tian-Chi;YANG Jian-Feng;ZHANG Hui-Ling(Institute of Geophysical and Geochemical Survey of Ningxia Hui Autonomous Region,Yinchuan 750004,China)
出处
《物探与化探》
2025年第4期943-953,共11页
Geophysical and Geochemical Exploration
基金
宁夏回族自治区重点研发计划项目“宁夏石嘴山地区土壤硒元素生态效应研究与应用”(2021BG03015)
宁夏回族自治区地质勘查基金项目“石嘴山地区富硒土地质量调查评价”(HZ20170040-Ⅲ)。
关键词
重金属
生物富集
相关性
健康风险评价
土壤环境
heavy metal
bioconcentration
correlation
health risk assessment
soil environment
