Lake Dianchi is the sixth freshwater of China and it has lost its lucidity and beauty because Aphanizomenon flos-aquae blooms often take place now. Aphanizomenon flos-aquae is the dominant bloom-forming species in spring and winter while microcystin instead of Aphanizomenon flos-aquae in summer and autumn of Lake Dianchi, so we should notice biological diversity of watershed and blooms condition which will happen. Aphanizomenon flos-aquae excreted amout of extracellular polymeric substances (EPSs) in...