Hg~(2+)与Cr(VI)对富营养化水体中藻类生长的毒性效应

目的]研究Hg2+与Cr(VI)对富营养化水体中藻类生长的毒性效应,为富营养化水体的生物监测以及生物修复提供参考依据。方法]分别用不同浓度的Hg2+、Cr(VI)以及两者的混合营养液培养从富营养化水体中分离的藻母液,观察Hg2+与Cr(VI)对藻类生长繁殖的毒性效应。结果]富营养化水体中的藻类对Cr(VI)表现相当敏感,当Cr(VI)浓度超过1mg/L时即对藻类的生长产生了明显的影响。在Hg2+浓度较低时,藻类对Hg2+不是十分敏感,当Hg2+浓度增大至一定程度,毒性愈来愈强,而Cr(VI)毒性效应则相反。当离子浓度小于10mg/L时,Hg2+对藻类的毒性低于Cr(VI),大于10mg/L时,Hg2+毒性超过Cr(VI)。Hg2++Cr(VI)混合离子对藻类生长的抑制具有协同作用,但只有当浓度超过4mg/L时才表现出来。结论]重金属离子对藻类的毒性不但与藻细胞本身有关,还与重金属离子的浓度有关。

Toxicity Effect of Hg2+ and Cr(VI)on Alga Growth in Eutrophic Water

Objective] The toxicity effect of Hg2 and Cr(VI)on alga growth in eutrophic water was studied to provide reference for bio-monitoring and bioremediation of eutrophic water. Method] The mother liquids of alga, which was separated from the eutrophic water, were put into the solutions of Hg2 and Cr (VI) with different concentrations and their mixture solution resp. and the toxicity effect of Hg2 and Cr(VI) on the growth and propagation of alga in eutrophic water was observed. Result] The alga in eutrophic water performed rather sensitive to Cr(VI) and when its concentration was over 1 mg/L, it made obvious effect on alga growth. The alga was not very sensitive to Hg2 when its concentration was lower, but its toxicity was stronger and stronger when its concentration increased to some extent and the toxicity effect of Cr(VI)on alga growth was just on the contrary. When the ion concentration was lower than 10 mg/L, the toxicity of Hg2 on alga was lower than that of Cr (VI).When the concentration was over 10 mg/L, the toxicity of Hg2 exceeded that of Cr(VI). The toxicity of ion mixture solution of Hg2 and Cr(VI) had synergism inhibition on alga, which could be performed only when the concentration was over 4 mg/L. Conclusion] The toxicity of heavy metal on alga not only related to the alga cell, but also related to the concentration of heavy metal ion.