红树植物秋茄对菲污染沉积物的根际修复研究

Rhizosphere Remediation of Phenanthrene-contaminated Sediment by Kandelia candel(L.) Druce

利用盆栽试验方法,研究了红树植物秋茄（Kandelia cande（lL.） Druce）对多环芳烃菲污染沉积物的修复作用。结果表明,在5、10、20、40mg·kg^-1菲处理浓度下,菲对秋茄的生长具有抑制作用,沉积物中菲初始浓度越高抑制作用越明显。4个月的修复试验结果表明,与无植物对照相比,种植秋茄能够明显促进沉积物中菲的降解。根际沉积物中菲的去除率为69%-82%,而非根际沉积物中菲的去除率为59%-66.9%。相同污染水平处理下根际沉积物中菲残留浓度低于非根际沉积物,而菲降解菌数量、多酚氧化酶和脱氢酶活性高于非根际沉积物,从而提高了沉积物中菲的降解率。

Rhizosphere-remediation of phenanthrene（PHE）-contaminated sediment with Kandelia candel（L.） Druce was investigated in soil-culture medium. The results showed that the growth of Kandelia candel was inhibited by PHE in a dose-dependent way at 5, 10, 20 or 40 mg·kg-1 of the studied PHE concentrations. On the other hand, Kandelia candel significantly promoted the degradation of PHE in sediment. After 4 months, 69%~82% and 59%~66.9% of the spiked PHE disappeared from the rhizospheric and the non-rhizospheric sediments, respectively. The residual concentration of PHE in the rhizosphere was lower than that in the non-rhizosphere at the same treatment concentration. Planting Kandelia candel enhanced the number of PHE-degrading bacteria and the activities of polyphenol oxidase and dehydrogenase, thus it improved the degradation rate of PHE. Taken together, our results suggested that planting Kandelia candel could strengthen the remediation of PHE-contaminated sediment.