岩溶区典型石灰土Cd形态指示意义及风险评价——以桂林毛村为例  

Implications of Cadmium Forms and Risk Assessment of Calcareous Soil in Karst Area:A Case Study of Maocun in Guilin,China

作　　者：周长松[1] 邹胜章[1] 李录娟[1] 朱丹尼 卢海平[1] 夏日元[1] 

机构地区：[1]中国地质科学院岩溶地质研究所/国土资源部岩溶动力学重点实验室/岩溶生态系统与石漠化治理重点实验室,广西桂林541004

出　　处：《吉林大学学报（地球科学版）》2016年第2期552-562,共11页Journal of Jilin University：Earth Science Edition

基　　金：国土资源部地质调查项目(1212011121166;121237131301101;2002371120029;1212011220959);国家重点基础研究发展计划(国家"973"计划)项目(2011CB201001);中国地质科学院岩溶地质研究所基本科研业务费项目(2014030;2015016)~~

摘　　要：为了了解岩溶区石灰土中重金属Cd形态分配特征及富集情况,在桂林毛村采集了3种处于不同发育阶段的黑色、棕色和红色石灰土进行研究。通过原子光谱仪测试了Cd质量分数,运用改进的Tessier分析法测定了3种石灰土中Cd的可交换态(EXC)、碳酸盐结合态(CAB)、铁锰氧化物结合态(OXI)、有机结合态(ORG)、残渣态(RES)5种形态,并对其指示意义及风险进行了分析与评价,结果表明,3种石灰土中Cd质量分数从大到小依次为早期黑色石灰土、中期棕色石灰土、晚期红色石灰土。形态测试结果表明:黑色石灰土和棕色石灰土中Cd形态以铁锰氧化态和残渣态为主,占土壤Cd质量分数的63%以上,且5种形态质量分数从大到小顺序均为铁锰氧化态、残渣态、可交换态、碳酸盐结合态、有机结合态;红色石灰土Cd形态以残渣态为主,占土壤Cd质量分数的76%,形态分配特征从大到小为残渣态、铁锰氧化态、可交换态、碳酸盐结合态、有机结合态。Cd稳定度和富集程度评价结果表明:在黑色石灰土、棕色石灰土和红色石灰土中Cd稳定度逐渐减小,环境二次释放风险逐渐降低;富集程度从大到小依次为黑色石灰土、棕色石灰土、红色石灰土,其中Cd在黑色石灰土中呈显著富集状态,在棕色石灰土中呈中度富集状态,在红色石灰土中呈轻微富集状态。潜在生态风险评价和健康风险评价结果表明,由早期黑色石灰土到中期棕色石灰土和晚期红色石灰土,土壤中Cd的生态风险和健康风险均逐渐降低。研究结果可为岩溶区土壤重金属Cd污染修复与治理提供基础数据。In order to grasp the forms and accumulation of cadmium in the soils of karst area,three calcareous soil samples collected from Maocun,Guilin,were analyzed.Their cadmium concentration was tested by an atomic spectrometer,and the cadmium was tested by an improved.Tessier assay,for its different existing status as it is in the five forms of EXC（exchangeable）,CAB（carbonate combined）,OXI（Fe-Mn oxide combined）,ORG（organic combined）and RES（residual）.Moreover,its risk to the environment and implications were analyzed and evaluated.The results showed that the relative cadmium contents of the three calcareous soil are：Black calcareous soil〉Brown calcareous soil〉Red calcareous soil;Cadmium in Black calcareous soil and Brown calcareous soil present mainly in Fe-Mn oxide combined form,and the chance to find it in other forms is reduced by the order of OXI〉RES〉EXC〉CAB 〉ORG.In Red calcareous soil,the relative contents of cadmium in different chemical forms reduced in the order of RES〉OXI〉EXC〉CAB〉ORG.The results of RSP and RACshowed that cadmium contents of the three calcareous soil are：Black calcareous soil〉Brown calcareous soil〉Red calcareous soil.The ecological and health risks of cadmium of the three calcareous soil are：Black calcareous soil 〉Brown calcareous soil 〉Red calcareous soil.The results provide basic data for remediation and control of cadmium in karst area.

关 键 词：石灰土 镉 重金属 形态 岩溶区 风险 

分 类 号：S512[农业科学—作物学]