Relationship Between Algal Bloom and Phosphorus in Water Environment in Zhushan Bay, Taihu Lake

Algal bloom in eutrophication water, which can cause various risks, are closely related to phosphorus concentration of water environment, especially endogenous phosphorus. In this study, the relationship between algal bloom and phosphorus in water environment was investigated by collecting water and sediment in three different time in 2019 in Zhushan Bay, Taihu Lake. The result showed that algal bloom occurred during 27 June to 28 September in 2019. A large amount of phosphorus in overlying water was absorbed at the initial stage of algal bloom and sediment played as “source” to supplement AAP for bloom forming, which was mainly NAIP. Large phosphorus released at the decay period of algal bloom was largely OP and adsorbed by sediment, which played as “sink” of phosphorus. Moreover, the main phosphorus form of TP in the sediments of Zhushan Bay was IP, in which main component was NAIP. The main component of AAP was NAIP that phosphorus combined with iron, aluminum, and other metals. Furthermore, phosphate-solubilizing microorganisms in the sediments of Zhushan Bay were mainly Alcaligenes, which could release phosphorus in sediment into overlying water to supplement phosphorus source required for algae bloom outbreak. The results of this study showed that endogenous phosphorus played an important role in the outbreak of algal blooms, and the control of endogenous phosphorus should be the key step of algal bloom control.