微囊藻群体的形成、增大和形态的持久维持是微囊藻获得种群优势进而形成水华的前提之一。微囊藻群体的形成可能是浮游动物牧食及环境因子等多种因素共同作用的结果。重金属离子为爆发蓝藻水华的富营养化水体中常见污染物。我们前期研究发现自然水体中微囊藻群体的形态大小与藻体的铅、镉、铬、铝、铁及锰元素含量均呈显著的正相关关系，且实验研究发现Pb2+在一定浓度范围内能够显著提高微囊藻胶鞘多糖的含量，并促进铜绿微囊藻群体的形成。本项目拟在摸清微囊藻对不同类别重金属离子吸附特征的基础上，明确重金属离子在微囊藻群体形成的作用，并通过研究主要效应重金属离子对微囊藻细胞的胶鞘多糖含量、胶鞘多糖单糖组分及与胞外多糖合成相关蛋白表达的影响，阐明重金属离子在微囊藻群体形成中作用机制。研究结果将对摸清微囊藻群体形成机制及揭示微囊藻水华爆发机理具有非常重要的意义，也可为微囊藻水华预警及有效治理提供科学准确的参考数据。

The formation, increase, maintenance of Microcystis colony provides a competitive advantage over other phytoplankton species. The formation of Microcystis colony may be impacted by zooplankon grazing and many environmental factors. Heavy metals ions were common pollutants in eutrophic waters, which frequently occurring cyanobacterial blooms. In preliminary studies, we have found the contents of lead, cadmium, chromium, aluminium, ferrum, and manganese of Microcystis were significantly positive with the size of the Microcystis colony in natural waters, and lead(II) could significantly increased the content of bound extracellular polysaccharides and promoted colony formation of Microcystis in the appropriate concentration range. Action rules of main effective heavy metals ions on the colony formation of Microcystis under controlled laboratory conditions will be studied on the basis of making clear the accumulation rule of heavy metals ions by Microcystis. The mechanisms of the action rules above will be studied by analysis of the effects of main effective heavy metals ions on the content and monosaccharide composition of bound extracellular polysaccharides, and the expression of proteins relation to the synthesis of bound extracellular polysaccharides of the algal cells of Microcystis. The results of the present project will play a very important role in making clear the colony formation of Microcystis and revealing the mechanism of outbreaking of Microcystis bloom, and provide abundant scientific reference data for monitoring and controlling of Microcystis bloom, and provide basic scientific data for biotreating of heavy metals contaminated waters.