Study On Water Purification Capacity Of Baiyangdian Lake Based On WASP Water Quality Prediction Model

Baiyangdian Lake is a semi-closed shallow water lake located in the plain area,which is an important part of water resources in North China.It has important service functions.It not only provides material resources for the surrounding areas,but also undertakes important tasks such as flood alleviation,water storage irrigation and biodiversity protection.However,with the rapid development of national economy,the increasing pace of industrialization and urbanization,coupled with the weak awareness of environmental protection of local residents in recent years,a large number of industrial and agricultural wastewater and domestic sewage are directly discharged into the water body of Baiyangdian Lake without treatment,resulting in the increasingly serious problem of eutrophication.Water quality model refers to the description and Simulation of the complex migration and transformation process of water containing substances due to the physical and chemical effects in the water by using mathematical expression.Through the water quality model,we can not only understand the process of water quality change,but also evaluate the effect and existing problems of physical,chemical,biological and other factors in lake water,which is of great significance for improving the lake and ecological remediation of pollution.With the continuous development of science and technology,water quality simulation technology is also constantly improved and updated.More and more water quality models have been developed and applied to real life,which has become an important means to understand the process of lake water quality change.Based on the water quality characteristics and hydrodynamic conditions of Baiyangdian Lake,this paper selects wasp water quality prediction model as the basic tool to simulate the migration and transformation of total nitrogen and total phosphorus in Baiyangdian Lake,to verify the feasibility and applicability of wasp water quality prediction model to Baiyangdian Lake water quality simulation,and to use wasp water quality prediction model to purify Baiyangdian Lake To evaluate the purification ability of Baiyangdian to total nitrogen and phosphorus,to analyze the effect of aquatic plants,aquatic animals and water conservancy conditions on the purification ability,and to put forward the ways and methods to improve the purification ability of Baiyangdian,so as to provide guidance and suggestions for the ecological restoration of Baiyangdian.Finally,the results show that:(1)the annual average nitrogen absorption capacity of Baiyangdian is 3.43% / d,and the phosphorus absorption capacity is 7.03% / d;(2)from the middle of November to the middle of March,the wetland aquatic plants release nitrogen and phosphorus to the water,and from the middle of March to the middle of November,they absorb nitrogen and phosphorus;(3)the purification capacity of wetland for nitrogen and phosphorus decreased with the increase of zooplankton concentration;(4)the depth of the forebay was 1.5m,and the hydraulic retention time was about 3 days.Based on this,the paper puts forward the ways to improve the purification capacity of Baiyangdian Lake:(1)planting cold tolerant aquatic plants to enhance the absorption capacity of nitrogen and phosphorus in the cold season of wetland;(2)fishing aquatic plants in time before the middle of November to avoid water pollution;(3)stocking filter feeding benthos and molluscs to control the content of zooplankton;(4)setting up a front-end reservoir with a hydraulic retention time of about 3 days and a depth of 1.5 Below m,to promote the settlement of pollutants in water.