福建龙海土壤重金属含量特征及影响因素研究  

Study on Concentration Characteristics and Influencing Factors of Heavy Metals in Soils in Longhai,Fujian Province

作　　者：孙凯 孙彬彬[1,2] 周国华[1] 贺灵 曾道明[1,2] 吴超[1,2] 成晓梦 SUN Kai;SUN Binbin;ZHOU Guohua;HE Ling;ZENG Daoming;WU Chao;CHENG Xiaomeng(Key Laboratory of Geochemical Exploration,Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang,Hebei 065000,China;International Center yo Global-scale Geochemistry,Unitee Nations Educational Scientific ann Cultural Organization,Lanfanf,Hebei 065500,China;China University of Geosciences,Beijing 100083,China)

机构地区：[1]国土资源部地球化学探测重点实验室,中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000 [2]联合国教科文组织全球尺度地球化学国际研究中心,河北廊坊065000 [3]中国地质大学(北京),北京100083

出　　处：《现代地质》2018年第6期1302-1310,共9页Geoscience

基　　金：国土资源部公益性行业科研专项(201411091-2)。

摘　　要：为有效预防土壤重金属生态风险,以福建龙海市表层土壤为研究对象,应用经典统计分析、随机森林等方法,研究重金属元素含量特征及其影响因素。结果表明:(1)第四纪冲洪(海)积成因水稻土中多数重金属元素含量较高;(2)燕山期中酸性岩风化形成的残坡积红壤中重金属元素活动态含量较高;(3) As、Cu、Ni形态含量与全量相关性较好,而Cd、Cr、Hg的多数形态含量与全量相关性较差;(4)除元素全量外,土壤有机质对弱有机结合态重金属(不包括Ni、Pb元素)以及离子交换态、碳酸盐结合态Cd、Zn有重要影响,阳离子交换量对各形态Ni,(Fe×Al)/Si对各形态Cu具有重要影响,而土壤成因、土壤类型对重金属形态组成的影响较小。研究表明土壤重金属形态组成及其富集区与其全量不尽一致,土壤重金属生态风险评价应考虑土壤重金属形态分布特征。To prevent ecological risk from heavy metals in soils in Longhai County,heavy metal concentration and their speciation characteristics as well as influencing factors of heavy metals were studied by classic statisti cal methods and random forest.The results show:(1)most heavy metals are enriched in paddy soils derived from Quaternary alluvial,deluvial or marine sediments;(2)the available contents of heavy metals in red soils in hilly and mountainous areas are relatively higher,which are derived from acid rock in Yanshanian age;(3)the speciation contents of As,Cu and Ni are correlated with their total contents,but the correlation is poor for Cd,Cr and Hg;(4)except for the total amount of elements,the effects of soil physico-chemical properties on the speciation of heavy metals are varied significantly.It presents that soil organic matter have great impact on the fraction contents of heavy metals of weak-bound to organic matter(except for Ni,Pb)as well as ion ex-changable and carbonate-bound fractions of Cd and Zn.The cation exchange capacity has effect on all forms of Ni.The ratios of(Fe XAl)/Si have effect on the fractions of Cu.However,soil origin and soil type seems to have little effect on heavy metal fractions.The study shows that the labile fraction of heavy metals is not corresponding to their total contents in most cases.Therefore,it is necessary to consider the speciation characteristics of heavy metals in soil when assessing their ecological risk.

关 键 词：土壤重金属 土壤成因 影响因素 随机森林法 福建龙海 

分 类 号：P595[天文地球—地球化学] X142[天文地球—地质学]