毛茛对富营养化水中多环芳烃的修复作用及机理

Phytoremediation of PAHs in Eutrophic Water by Ranunculus japonicus Thunb.

以菲为多环芳烃(PAHs)代表物,采用水培体系,研究了毛茛(RanunculusjaponicusThunb.)对富营养化水中菲的修复作用。结果表明,供试植物(毛茛)对水中菲有很好的修复效果,168h后,水中菲去除率达82%;与无植物对照相比,毛茛作用下菲的降解速率常数(K)增大96.7%,半衰期则缩短49.2%。毛茛明显吸收水中菲。实验条件下,0～168h,毛茛的菲含量先快速升高,48h时菲含量达到峰值(117.4mg·kg-1),而后趋于降低;0～168h,毛茛对水中菲的富集系数(PCF)则先升高而后趋于稳定。与无植物对照相比,毛茛对水中菲去除的促进作用主要来自植物本身的积累和代谢,而微生物的贡献甚微。同时,实验条件下,毛茛对水中氮(N)、磷(P)等也有很好的修复效果,168h后,水中N的去除率达89.6%,P元素则未检出。

Phytoremediation of PAHs, phenanthrene as a representative, in eutrophic water by Ranunculus japonicus Thunb. was studied. After 168 h, 82% of phenanthrene was removed from water in the presence of Ranunculus japonicus Thunb.. The degradation constant （K） was 96.7% larger and half-life of phenanthrene was 49.2% shorter in the presence of plant than those for unplanted-controls. The concentrations of phenanthrene in plant increased sharply in 0～168 h and decreased thereafter, and the highest concentration of phenanthrene in plant （117.4 mg·kg^-1） was observed at 48 h. While plant concentration factors （PCFs） increased first until reached a plateau in the uptake duration of 0～168 h. Compared with the unplanted control treatments, Ranunculus japonicus Thunb. significantly enhanced the degradation of phenanthrene in water, which owed mainly to the plant accumulation and metabolism of this PAHs, and microbial degradation contributed little to the enhaneement of phenanthrene dissipation. RanunculusjaponicusThunb. also showed a high remediation effieieney for N and P in water. After 168 h, 89.6% of N was removed from water, and P was not detectable at the end of uptake duration. These results would provide some useful information for cost-effective phytoremediation of inorganic-organic co-contaminated water bodies.