杞柳对水中2，4-二氯苯酚的降解

Degradation of 2,4-Dichlorophenol by Salix integra in Water

通过在人工配制的含有2,4-二氯苯酚(2,4-DCP,2,4-Dichlorophenol)的营养液中培养杞柳(Salixintegra),研究了杞柳在不同处理条件下对水溶液中2,4-DCP的去除效率,并探讨了其对2,4-DCP降解的动力学过程。结果表明,在抑菌和不抑菌处理条件下,杞柳对水溶液中的2,4-DCP有促进降解的作用,在96h内杞柳对20mg·L-1的2,4-DCP去除效率分别为:76.9%、81.1%,并且对2,4-DCP的去除都符合一级动力学方程;而没有杞柳生长的水体中2,4-DCP的降解率为0%。2,4-DCP的植物吸收降解、微生物降解对2,4-DCP去除的贡献率约为:92.57%、7.43%。在模拟光照下,杞柳在48h内能去除水中约52.37%的2,4-DCP。同时,根系组织中多酚氧化酶和过氧化物酶活性受到了2,4-DCP明显的抑制。试验所采用的质量浓度对杞柳没有产生毒害作用,表明杞柳是修复水中2,4-DCP较好的材料。

Phytoremediation, which uses plants to treat polluted sites and groundwater, is a low-cost and promising method for pollution control. In this paper, phytorcmediation of 2,4-Dichlorophcnol（2,4-DCP） in water solutions by Salix integra was investigated. The efficiency, kinetics and mechanism of Salix integra to degrade 2,4-DCP were studied. The results showed that： in sterile and non-sterile treatments, Salix integra promoted 2,4-DCP degradation significantly compared with the control, removing at most 76.9, 81.1% of 20 mg·L^-1 2,4-DCP in 96h, respectively, and without Salix integra was 0%. In the kinetics experiment, 2,4-DCP concentration was measured at various time. The kinetics of 2,4-DCP degradation by Salix integra fitted the first-order kinetics equation. And it demonstrated that plant uptake and degrade contributed about 92.57% to the total 2,4-DCP removal, while microorganism did about 7.43%. We also found the positive effect of light on 2,4 DCP degradation by Salix integra in water Although the activities of polyphcnoloxidasc and pcroxidasc in the roots ofSalix integra were restrained significantly by 2,4-DCP. Dose （ ≤20mg/L ） used in this study were not toxic to the test Salix integra. Therefore, Phytorcmediation of 2,4-DCP by Salix integra be considered an efficient treatment to 2,4-DCP polluted water.