农田土壤重金属污染“边生产边修复”综合防治技术模式解析

Analysis on integrated remediation model of“phytoremediation coupled with agro-production”for heavy metal pollution in farmland soil

我国农田土壤重金属污染形势严峻,已对农产品安全生产构成严重威胁。本文围绕农田重金属污染"源端控制-过程阻断-末端修复-安全利用"的技术路线,阐述了我国中轻度重金属污染农田"边生产边修复"综合防治技术模式的现有基础和瓶颈问题,总结了国内外重金属污染源解析方法的优缺点、我国当前农田重金属污染源监测与农田重金属钝化剂/活化剂开发利用的现状,估算了现有重金属富集/超富集植物地上部提取效率,分析了以低积累作物品种和种植结构调整为基础的农田安全利用技术应用的可行性,提出了我国农田土壤重金属污染综合防治技术有待进一步研究的问题,以期为我国土壤重金属污染治理提供参考。

Heavy metal pollution in farmland soil is serious in China and poses a threat to the safety in agricultural production.Based on the integrated technology of"source controlling,process blocking,end remediation and safety production",this paper concluded the current technologies and problems for"phytoremediation coupled with agro-production"of moderate and mild heavy metal polluted farmlands in China by literature review.For the sources controlling,the advantages and merits of the source apportionment methods and the field monitoring of heavy metal pollution sources were analyzed,and the application for the source identification methods and reduction technologies of pollution sources were clarified.Regarding the contaminated soil,we summarized the current applications of deactivators/activators and estimated the phytoextraction rate of heavy metals from the aboveground of accumulators/hyperaccumulators.The feasibility of the safety production technologies for heavy metal polluted farmlands was analyzed,which was based on planting low heavy metal accumulation varieties and changing crop systems.Finally,the related issues that need to be further studied on safety utilization of heavy metal polluted farmland soil were put forward.