Promoting the seasonal succession of submerged macrophytes by regulating the harvesting intensity of Potamogeton crispus

Harvesting is a direct and simple artificial method to regulate submerged macrophyte communities. However, there is still a gap in whether the succession of different seasonal submerged macrophytes can be achieved by harvesting. The morphological, physiological index, competition intensity of Hydrilla verticillata (H. verticillata) and underwater light under different harvesting intensities of Potamogeton crispus (P. crispus) was studied by a controlled experiment. Under moderate harvesting intensity (harvest 30% and 45% of plant height) of P. crispus, H. verticillata was the least inhibited, resulting in accumulating more Chl a and higher plant height. The underwater light created by moderate-intensity harvesting was favorable for H. verticillata to compete with P. crispus. Thus, moderate-intensity harvesting of P. crispus can promote the growth of H. verticillata. In practice, moderate harvesting intensity of P. crispus can be used to create conditions for the growth of summer species to achieve seasonal succession of submerged macrophytes and maintain the clear-water state of the lake.