Ecological effect of submerged plant Potamogeton crispus on TN in eutrophic water body and its model

Through the laboratory construction of nutrient salts and Potamogeton crispus biomass of orthogonal experiment, it studied the ecological effect of P. crispus on water TN during the period of turion germination to plants rot decay, and then its model was established. Research shows that due to the different biomass of P. crispus function, TN content in eutrophic water was first decreased and then increased. In the same nutrient levels in each group, the uptake of TN was increased by increasing biomass, while at the same biomass in each group, there was an optimum nutrient level between 13.95-20.56 mg·L–1 for the reparation of TN. The ecological effect model could be divided into two parts: the relationship of P. crispus on TN and time model, and ecological restoration of water body TN limit theory model. This model is helpful for the ecological restoration, and it can provide effective protection for engineering practice.