螯合剂对油葵修复镉砷复合污染土壤的影响

为提高油葵对农田土壤重金属的提取效率,研究了不同螯合剂(NTA、EGTA、EDDS和EDTA)对油葵修复Cd、As复合污染农田土壤的影响。结果表明,施用4种不同螯合剂对油葵根、茎、叶、花盘和籽粒生物量影响不大。不同螯合剂对油葵各器官Cd、As含量和积累量影响不一样。与CK处理相比,施用NTA、EGTA、EDDS、EDTA导致油葵花盘Cd含量分别提高30.2%、55.1%、41.9%和43.3%,根系As含量分别提高23.6%、18.1%、15.6%和15.4%,但是对籽粒和茎中Cd含量影响不显著。施用NTA、EGTA、EDDS和EDTA处理使油葵植株总Cd积累量分别比CK处理提高32.8%、45.3%、40.5%和41.6%,而对油葵As积累量没有显著影响。4种螯合剂对油葵各器官Cd、As富集系数有不同影响,而对Cd、As转运系数影响不显著。施用EDTA处理使根际土壤Cd含量比CK处理降低25.0%,施用NTA和EDTA处理使根际土壤As含量分别降低18.1%和14.3%。4种螯合剂均可以提高油葵对Cd、As污染土壤的修复效率。

Effect of chelating agents on remediation of cadmium and arsenic complex contaminated soil using oil sunflower

To identify measures to improve the heavy metal extraction efficiency of oil sunflower on farmland soil, the effect of different chelating agents (NTA, EGTA, EDDS, and EDTA) on the remediation of Cd and As complex-contaminated soil by oil sunflower were studied. The results showed the application of the four different chelating agents had little effect on the biomass of roots, stems, leaves, disk, and grain of oil sunflower. Different chelating agents had different effects on Cd and As concentrations and accumulation in different organs of the oil sunflower. Compared with the CK treatment, the application of NTA, EGTA, EDDS, and EDTA increased the Cd concentration in oil sunflower disk by 30.2%, 55.1%, 41.9%, and 43.3%, respectively, and the As concentration in oil sunflower root increased by 23.6%, 18.1%, 15.6%, and 15.4%, respectively. However, the effect on Cd concentration in oil sunflower grains and stems was not significant. Treatment with NTA, EGTA, EDDS, and EDTA increased the total Cd accumulation of oil sunflower plants by 32.8%, 45.3%, 40.5%, and 41.6%, respectively, but had no significant effect on the accumulation of As in oil sunflower. The four chelating agents had different effects on the Cd and As enrichment coefficients of oil sunflower but had no significant effect on Cd and As transport coefficients. Treatment with NTA and EDTA resulted in a decrease of 21.1% and 25.0%, respectively, in soil Cd concentrations and a decrease of 18.1% and 14.3%, respectively, in soil As concentrations. These four chelating agents can be used to improve the remediation efficiency of oil sunflower on Cd and As contaminated soil.