【摘 要】
:
[目的]河道底泥是土壤和水体重金属在地球化学循环中的特殊载体,而农业河道底泥作为农业生态系统中重金属污染的重要来源却被鲜少注意到.[方法]文章选取水系发达的上海市某处典型农业圩区,收集河道底泥,依照相关技术要求和标准进行镉(Cd)、汞(Hg)、砷(As)、铅(Pb)、铬(Cr)、铜(Cu)、镍(Ni)和锌(Zn)等8项重金属的含量检测,采用地积累指数结合检测结果的空间分异特征分析和讨论了研究区域内重金属的环境风险和特点.[结果]结果表明,研究区内农业河道底泥中重金属含量符合国家标准;部分样点Cu、Hg和P
【机 构】
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上海亚新城市建设有限公司,上海200436;自然资源部大都市区国土空间生态修复工程技术创新中心,上海200436
论文部分内容阅读
[目的]河道底泥是土壤和水体重金属在地球化学循环中的特殊载体,而农业河道底泥作为农业生态系统中重金属污染的重要来源却被鲜少注意到.[方法]文章选取水系发达的上海市某处典型农业圩区,收集河道底泥,依照相关技术要求和标准进行镉(Cd)、汞(Hg)、砷(As)、铅(Pb)、铬(Cr)、铜(Cu)、镍(Ni)和锌(Zn)等8项重金属的含量检测,采用地积累指数结合检测结果的空间分异特征分析和讨论了研究区域内重金属的环境风险和特点.[结果]结果表明,研究区内农业河道底泥中重金属含量符合国家标准;部分样点Cu、Hg和Pb超出当地背景值1倍以上,且Cu和Hg的地积累指数达到或接近了中风险;但样点检测值在空间上关联不明显.[结论]研究区农业河道重金属以点源来源积累为主的Cu和Hg为首、一定程度上受环境影响的Pb积累为次的重金属环境风险.
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