Aquatic Macrophyte Restoration Differentiation Model and Application on Shallow Lakes

Based on the analysis of the environmental factors involved in the growth of aquatic macrophyte,the differentiation function for aquatic macrophyte restoration under field conditions is proposed,which considers the intergrated impacts of various environmental factors including the underwater light,nutrients,suspended sediment,water current,temperature,and deposited sediment.Through the numerical simulation of different influencing factors,an aquatic macrophyte restoration differentiation model (AMRDM) is established based on the projection pursuit theory.The model is applied to study on the restoration area of Vallisneria gigantean L. in Gucheng Lake,located in the middle and lower reaches of Yangtze River.Under the present living condition in Gucheng Lake,the restoration area of Vallisneria gigantean L. is found to reach 3.25 km² approximately,which takes account for 10.5% of the total water surface area.Most of the restoration areas are concentrated in the north and the middle parts,and the restoration area in the south part,which is about 0.65 km²,is relatively small.