Cu2+对铜绿微囊藻生长及叶绿素荧光主要参数的影响研究

摘要

The effects of different Cu2+concentrations (0.16, 0.32, 0.66, 1.16, 2.16, 4.16μmol/L) in culture media on the cell density, chlorophyll-a content and chlorophyll fluorescence parameters (CFP) of Microcystis aeruginosa within the first 120h were investigated. It shows that Cu2+concentration had significant effects on the growth and chlorophyll-a content of Microcystis aeruginosa (P<0.05) from 12h to 120h by One-way ANOVA. The growth of Microcystis aeruginosa could be promoted as the Cu2+ concentration was between 0.32~1.16μmol/L and can be inhibited as that is below 0.16μmol/L or above 2.16μmol/L. The obvious effects on the CFPs of Fv/Fm,ΦPSⅡand ETR were not observed when the Cu2+concentration is below 2.16μmol/L. But the serious bad influences were found when the Cu2+concentration was 4.16μmol/L. Its values of Fv/Fm,ΦPSⅡ and ETR were much less than that of other Cu2+concentration (P<0.05), while shows the following changing trends: rapidly decreasing within the first 24h, then rapidly increasing within 24h~96h and finally slowly decreasing within 96h~120h.%研究了不同Cu2+浓度(0.16,0.32,0.66,1.16,2.16,4.16µmol/L)对培养基中铜绿微囊藻120h内的细胞密度、叶绿素a含量和3个主要叶绿素荧光参数的影响,并对Cu2+在灭藻时易复发的问题做出了一定解释.实验结果表明,当培养体系中Cu2+浓度在0.32~1.16µmol/L时,可促进铜绿微囊藻生长；当Cu2+浓度低至0.16µmol/L或高于2.16µmol/L时,可抑制铜绿微囊藻生长.当培养体系中Cu2+浓度小于2.16µmol/L时,对 Fv/Fm (光系统Ⅱ的最大光能转化效率)、ΦPSⅡ(光系统Ⅱ的实际光能转化效率)和 ETR(电子传递效率)3个荧光参数指标的影响不大；当Cu2+浓度为4.16µmol/L时,Fv/Fm、ΦPSⅡ和ETR呈现先快速下降,后有所回升,再缓慢下降的趋势,但整个时段均显著低于其他各浓度处理组(P<0.05),表现出明显的受抑制现象.