零价纳米铁对青梗菜吸收土壤铬的抑制效果探讨

Inhibition Effects of Nanoscale Zero-Valent Iron(nZVI)on Cr Absorption from Soil by Bok Choy

通过盆栽实验探讨不同铬污染水平农田土壤施加零价纳米铁对不同时期青梗菜吸收土壤铬的抑制效果。结果表明,零价纳米铁能够有效抑制青梗菜对铬的富集,且在施加铬铁质量比例为1∶20和1∶40时效果较好,与对照相比,青梗菜根、茎、叶铬含量最高减少量分别为66%、79%、78%。同一污染土壤,不同采集时期青梗菜体内铬含量无显著差异。青梗菜体内富集的铬含量与土壤总铬含量呈正相关,青梗菜对铬富集量呈现根部>茎部>叶部。

The inhibitory effects on Cr absorption by bok choy( Brassica rapa L. ssp. Chinensis L.) were studied by pot experiments and adding nanoscale zero-valent iron (nZVI) to different levels of chromium (Cr) contaminated soil. The results showed that nZVI could effectively reduce Cr accumulation in bok choy,the optimal additive ratio of nZVI were 1 ∶20 and 1 ∶40. Compared to the control group,the concentration of Cr in root,stem and leaf reduced by 66%,79%,78%,respectively. In the same contaminated soil,no significant difference of Cr absorption was found in different growth period of bok choy. The accumulation of Cr in bok choy was positively correlated with the total concentration of Cr in the soil.The sequence of Cr concentration in bok choy from high to low was root,stem and leaf.