水培海马齿对海水菲污染修复作用的初步研究

采用水培法研究了海洋滩涂耐盐植物海马齿(Sesuvium portu lacastrum Linn.)对海水菲污染的修复作用.结果显示,实验4d后,不种植海马齿的对照组、种植海马齿的抑菌组和不抑菌组海水中菲浓度分别从0.988、0.942和0.957mg·L-1降至0.553、0.185和0.070mg·L-1,降低了44.0%、80.4%和92.7%;与对照组相比,抑菌组(T1)和不抑菌组(T2)海水中菲的去除率分别提高了36.4%和48.7%,不抑菌组又比抑菌组高12.3%.利用差减法计算的结果显示,在与自然水体接近的不抑菌条件下,菲的非生物损失、海马齿的作用和微生物的作用,三者对海水中菲浓度降低(92.7%)的贡献分别为44.0%、36.4%和12.3%,海马齿植株内菲的积累量则仅占海水中菲减少量的2.6%.研究表明,水培海马齿可明显提高菲污染海水中菲的去除率,其中,植物与微生物共同发挥着重要的作用,但植物积累不是海马齿修复海水菲污染的主要机制.

A preliminary study on phytoremediation of phenanthrene by a marine halophyte Sesuvium portulacastrum Linn. in hydroponic cultures

Phytoremediation of phenanthrene by marine halophyte Sesuvium portulacastrum Linn. was studied through a hydroponic culture approach. The results showed that, after 4 days incubation, the concentration of phenanthrene in the culture medium of the unplanted control group (CK), the planted treatment group with sterilization (T₁) and without sterilization (T₂) reduced from 0.988, 0.942 and 0.957 mg·L^-1 to 0.553, 0.185 and 0.070 mg·L^-1, respectively, i.e. the reduction rate was about 44.0%, 80.4% and 92.7% for CK, T₁ and T₂ respectively. Comparing with that of CK, the increase of phenanthrene removal rate was about 36.4% and 48.7% for T₁ and T₂ respectively, corresponding to a 12.3% higher for T₂ than T₁. By subtraction method, the contribution of phenanthrene removal caused by abiotic loss and that through the agency of plant and microbes were calculated to be 44.0%, 36.4% and 12.3%. It should be noted that the non-sterile group was similar to that of natural waters. However, in such cases, the accumulation of phenanthrene inside the plant only accounted for 2.6%. It was suggested that the hydroponic Sesuvium portulacastrum Linn. could significantly enhance the removal of phenanthrene in seawater, where the plant and the associated microbes might play a major role in the removal processes. Results also suggested that phytoaccumulation mechanism was not as important as expected for Sesuvium portulacastrum Linn. in the remediation of phenanthrene.