硅酸盐、腐殖酸对Cr污染土壤中小白菜生理及吸铬量的影响

Effect of silicates and humic acid on physiology and Cr uptake by Brassica Chinensis under stress of Cr contamination

针对在铬污染区土壤中的叶菜类吸铬量是果菜类2～3倍,以及硅酸盐或腐植酸在重金属污染土壤上的最佳施用量研究较少的问题,为保障蔬菜的品质安全,文章通过土壤盆栽试验,研究硅酸盐、腐殖酸不同用量对Cr污染土壤中小白菜(Brassica Chinensis)生理指标和吸铬量的影响。结果表明,施低质量分数的硅酸盐(1.0g·kg-1)效果最佳,既能提高受Cr污染小白菜的生物量、叶绿素相对含量,又能减轻Cr毒害对抗氧化酶系统中SOD酶活性的抑制,缓解小白菜受到的过氧化胁迫,有效降低小白菜吸铬量;高质量分数硅酸盐(2.0g·kg-1)对生长产生抑制。腐殖酸在设计的3个质量分数水平上均不能有效降低小白菜吸铬量,对生长的促进作用也不明显。

In Cr polluted area, leaf vegetable＇s Cr uptake is 2-3 times as much as fruit vegetable＇s. Aiming at optimization of manuring level of silicates and humic acid, pot experiments were carried out to study the effects of silicates and humic acid on physiology and Cr uptake by Brassica Chinensis. The results indicated that the treatment of 1.0 g·kg^-1 silicates has the best effect, it not only improved biomass and chlorophyll relative content, but also promoted the activity of SOD, alleviate damage of membrane lipid peroxidation of plasma membrane, decreased the Cr uptake effectively. While 2.0 g·kg^-1 silicates inhibited the growth. Humic acid can＇t decrease the Cr uptake in all level, and its promoting effect on physiology were not satisfied.