根分泌物与微生物对污染土壤重金属活性的影响

研究了铜富集植物海州香薷(Elsholtziasplendens)和鸭跖草(Commelinacommunis)根分泌物,以及假单胞菌(P.aeruginosaZD4-3)和白腐真菌(P.Chrysosprim)对污染土壤重金属活性的影响.结果表明,海州香薷和鸭跖草根分泌物对污染土壤中Cu有一定的活化能力,不同处理间差异不大,鸭跖草根分泌物对Cu的活化能力大于海州香薷.不同处理根分泌物中有机酸种类或含量有所差异,但主要以草酸和出峰时间为6.5min左右的未知有机酸为主.假单胞菌对污染土壤Cu、Pb和Zn有很强的活化作用;白腐真菌对Cu、Zn有活化作用,对Pb则表现为固定作用,海州香薷根分泌物降低了供试假单胞菌对重金属的活化效果,但增加了白腐真菌对重金属的活化效果.

The influence of root exudates and microbe on heavy metal activity in contaminated soil

The influence of root exudates of the copper abundant plants Elsholtzia splendens and Commelina communis, and the microbes P. aeruginosa ZD4-3 and P.Chrysosprim, on the heavy metal activity in contaminated soil were studied. The root exudates of these two plants had definite activating ability on Cu in contaminated soil, and there was no significant difference among different treatment, with the ability of Commelina communis root exudate greater than that of Elsholtzia splendens. The kind or the content of organic acid in the root exudates was different among different treatments; but the main organic acids were oxalic acid and the unknown organic acid with 6.5min spearhead time. These two microbes had very great activation on Cu, Pb and Zn in contaminated soil. P. aeruginosa had activation on Cu and Zn, and solidifying function on Pb. Root exudates of Elsholtzia splendens decreased the activation effect of the microbes on heavy metals, while increased the activation effect of P.Chrysosprim on heavy metals.