Effect of Artificial Mixing on Temporal and Spatial Succession of Algae Community Structure in Jinpen Reservoir

Abstract

To explore the effect mechanism of the artificial mixing process on the temporal and spatial succession of algae community structure in a water body, this study used water-lifting aerators to induce in-situ artificial mixing of the water body of Jinpen Reservoir, and in-situ spot physical-chemical parameters and algae of the water body of the reservoir were observed during an artificial mixing process. A total of 51 species of 28 genera of 6 families of algae were identified in the water body of the Jinpen Reservoir. The artificial mixing effect of the water-lifting aerators significantly inhibited the growth of algae in the water, and had a significant impact on the community structure. Before activation of the water-lifting aerators, algae were mainly distributed in the surface water body, and Chlorella vulgaris was the dominant species. With the operation of the water-lifting aerators, the algal density of surface water body decreased significantly, and the vertical distribution of the algae density in the water body tended to be uniform. The dominant species tended to succeed in Cyclotella sp. This study used the method of redundancy analysis, combined with critical depth theory and the characteristics of algae growth, to analyze the relationship between the spatial-temporal succession of algae community structure and the changes in the main physical-chemical parameters in Jinpen Reservoir during the artificial process. The analysis results showed that the artificial mixing of the water-lifting aerators mainly affects the temporal and spatial succession of the algae community structure by rapidly destroying the thermal stratification stability of the water body and significantly increasing the water mixing depth.