湘阴县重金属污染耕地水稻钝化修复技术研究

Study on passivation repair technology of cultivated rice in Xiangyin County

耕地重金属污染是影响国计民生的重要问题。本文以湘阴县重金属污染耕地为研究对象,参考前人土壤修复方面成果,提出了“矿物改性复合钝化—二次阻隔—增值修复”技术思路。选取蒙脱石等4种黏土矿物按不同比例混合,细磨(-400目)—超细磨(-600目)配制出2种矿物改性复合钝化剂,采取以本次配制的2种矿物改性复合钝化剂为主,平行开展11种钝化处理,通过小区试验与大田示范同步进行。经验证,本次研制的改性复合钝化剂2+石灰+硅肥组合(GXFH-2+SH+SI)修复技术,能有效削减重金属污染耕地稻米Cd含量,并能有效增加稻米中有益元素Se含量,是一种成本低、效果好、操作简便的重金属污染耕地钝化修复技术,可推广应用。

Heavy metal pollution in cultivated land is an important issue affecting the national economy and people's livelihood.Herein,heavy metal contaminated farmland in Xiangyin County is taken as the research object,a technical approach of‘mineral modified composite passivation secondary barrier value-added remedia-tion’is proposed referring to previous achievements in soil remediation.Four kinds of clay minerals such as montmorillonite are selected and mixed in different proportions,fine grinding(-400 orders)and ultrafine grinding(-600 orders)are selected to prepare two kinds of mineral modified compound passivation agents.Two kinds of mineral modified compound passivation agents are utilized to carry out 11 kinds of passivation treatment in paral-lel,which is carried out simultaneously through community test and field demonstration.It is proven that the developed repair technology of modified compound passivation agent 2+lime+silicon fertilizer combination(GXFH-2+SH+SI)can effectively reduce Cd content and increase the beneficial elements Se in rice of heavy metal pollu-tion farmland.It is demonstrated a kind of heavy metal pollution farmland passivation repair technology with low cost,favorable effect and easy operation,which can be promoted and applied.