狼尾草等6种植物对十溴联苯醚污染土壤的生理响应及其修复效果

考察了狼尾草、龙葵、空心菜、苣菜、芥菜和鱼腥草6种植物对土壤中十溴联苯醚（BDE-209）的生理响应及其修复效果。结果表明,在BDE-209污染条件下,供试植物体内丙二醛（MDA）含量升高,表明植物受到一定的毒害作用,而在植物抗逆境机制作用下,植物体内可溶性蛋白质含量升高,超氧化物歧化酶（SOD）活性下降;在供试植物生物量方面,BDE-209对龙葵、空心菜和狼尾草地上部有促进作用,而对苣菜、芥菜具有一定的抑制作用;6种修复植物体内均检测出BDE-209,且地上部与根部BDE-209含量具有显著差异,其中狼尾草根部干重含量高达16.93mg·kg-1;修复60d后,土壤中BDE-209含量均有一定程度的下降,最高去除率可达40.44%,且根际土与非根际土BDE-209去除率有显著差异。修复效果依优劣次序为狼尾草〉龙葵、空心菜〉鱼腥草〉芥菜〉苣菜。

Research on the Physiological Responses of Six Plants Pennisetum Alopecuroides Etc to BDE-209 in Soil and Their Phytoremediation Effect

The physiological responses of plants Pennisetum alopecuroides, Solanum nigrum, Ipomoea aquatica Forsk, Sonchus brachyotus D C, Brassica juncea and Houttuynia cordata Thunb to contaminant BDE -209 in soil were investigated, and the phytoremediation effects of these plants on BDE-209 contamination were explored. The results indicated that, the contents of MDA in tested plants increased under the condition of BDE-209 pollution, revealing that the plants suffered from toxic effect to a certain extent. Meanwhile the increased soluble pro- tein content and decreased SOD activity were also detected, due to the mechanism of adversity resistance in plants, In respect of biomass of tested plants, BDE-209 promoted the growth of shoots of Pennisetum alopecuroides, Solanum nigrum and Ipomoea aquatica Forsk, but inhibited that of Sonchus brachyotus D C and Brassica juncea to a certain degree. The contents of BDE-209 in all six plants were detected with significant difference existed in shoots and roots. Among these a content of as high as 16.93 mg·kg-1 BDE-209 has been found in the root dry weight of Pennisetum alopecuroides. The concentration of BDE-209 in soil has decreased to some extent after 60 days remediation and the maximum removal efficiency of BDE-209 reached 40.44%. BDE-209 removal rate of rhizosphere soil differed significantly from that of non- rhizosphere. The sequence of the plants with remediation effect from high to low in turn was Pennisetum alopecuroides, Solanum nigrum and Ipomoea aquatica Forsk, Houttuynia cordata Thunb, Brassica juncea, Sonchus brachyotus D C.