螯合剂修复对尾矿土壤性质和紫穗槐生长影响及其相关性分析

Effect of chelating agents on properties of tailing soil and growth of amorpha fruticosa and the correlation analysis

针对不同螯合剂配比修复措施对尾矿土壤综合性质、植物生长指标的影响及二者相关性,采用IDS、EDTA 2种螯合剂-紫穗槐联合修复尾矿土重金属进行盆栽试验。结果表明:(1)紫穗槐在不同的螯合剂配比改良处理措施下的株高、主根长、根茎均呈现先减后增的变化趋势,单独加入EDTA比单独加入IDS的抑制作用强,适当调整IDS、EDTA的混合处理配比可促进植物生长。(2)单一的IDS对电导率有抑制作用,而IDS与EDTA混合处理、单一的EDTA对电导率有促进作用。(3)对照组(用水培养)Cu含量最高,单一的IDS对Cu含量有明显促进作用,无论是单因素处理还是IDS、EDTA的混合处理对Pb、Zn含量均有抑制作用。(4)土壤中有机质含量与植物生长指标呈负相关,而电导率与植物生长指标呈正相关,土壤电导率与植物的根茎相关性极高,土壤pH值与植物生长指标的负相关性不大。(5)植物生长指标与Cu含量、Zn含量有着较高的正相关性,而Pb含量的高低对植物生长指标影响不太明显。

In view of the effects of different chelating agent ratios on tailings soil properties,plant growth indexes and their correlation,a pot experiment was carried out by using IDS and EDTA chelating agents combined with Afrua pseudoacacia to remediate heavy metals in tailings soil.The results show that the plant height,main root length and rhizome of Amorpha fruticosa decrease first and then increase under different chelating agents ratios.The inhibition effect of EDTA alone is stronger than that of IDS alone,and appropriately adjusting the mixing ratio of IDS and EDTA can promote plant growth.Single IDS can inhibit the conductivity,while single EDTA,or IDS mixed with EDTA can promote the conductivity.The Cu content is the highest in the control group(water culture).The single IDS significantly promotes the Cu content,and either single factor treatment or the mixed treatment of IDS and EDTA inhibit the contents of Pb and Zn.Soil organic matter content is negatively correlated with plant growth indexes,while electrical conductivity is positively correlated with plant growth indexes.Soil electrical conductivity is highly correlated with plant rhizome.There was no significant negative correlation between soil p H and plant growth index.The plant growth index has a high positive correlation with the content of Cu and Zn,but the influence of Pb content on the plant growth index is not obvious.