Effect Evaluation On Ecological Restoration And Study On Technical Suitability Of Yongding River Plain In Beijing

The river system is one of the most important ecosystems in nature.However,with the development of human economy and society,the demand for rivers has continued to increase,unreasonable development and utilization and the discharge of large amounts of pollutants have caused serious damage to river ecosystems.With the increasing awareness of ecological environment protection,human beings began to realize the importance of restoring river ecology."Ecological restoration" has become an important concept for the management of river ecology.A large number of ecological restoration technologies have been proposed and applied to river management projects.The Yongding River is the mother river in Beijing.In recent years,Beijing has adopted a variety of ecological restoration techniques to carry out comprehensive remediation of this section of the river and has achieved certain results.Taking the Yongding river plain section of Beijing as the research object,this paper evaluates the ecological restoration effect,and carries out preliminary analysis and study on the suitability of ecological restoration technology,so as to provide basis for the comprehensive management and ecological restoration of Yongding river in Beijing.The main results were as follows:(1)In the evaluation of ecological restoration effect in the plain section of Yongding River in Beijing,this paper first establishes 12 evaluation index systems that embody the ecological function of river water,the function of water environment and the function of social service.The evaluation results of ecological restoration are divided into four levels: better,good,general and poor.The evaluation matrix of ecological restoration effect is established by AHP,and the evaluation results are quantified.The calculation shows that the water ecological restoration effect of the Yongding River plain section in Beijing scored 2.323,and the grade is general;Water environment repair effect scored 3.274,the grade is better;The social service effect score is 2.741 and the rating is good.The overall evaluation score of ecological restoration effect is 2.743,and the grade is good.That is,by 2016,the ecological restoration effect of the Yongding River Plain section in Beijing has reached a general situation.The results are basically in line with the actual effect of ecological restoration in the plain section of Yongding River.(2)According to the restoration goal,the main task of management,the amount of water resources and the actual situation of water ecological environment in the plain section of Yongding River in Beijing,this paper makes a preliminary study on the suitability of the ecological restoration technology of this section of river.According to the study,there are 17 kinds of restoration technologies in five categories,including river water ecological restoration technology,riverbank ecological restoration technology,shoreline and shore slope comprehensive ecological protection technology,river habitat creation technology,and bio-ecological purification technology.The ecological restoration of the Yongding River plain section in Beijing is suitable for 9 technologies such as water diversion and replenishment,3 technologies such as ecological island technology are less suitable,and 5 technologies such as chemical restoration are not suitable.(3)Based on the study on the suitability of ecological restoration technology,this paper proposes that the ecological restoration model for the northern section of the Yongding river plain in Beijing should be water diversion,water replenishment,artificial lake,wetland,shallow lake,anti-seepage,and plant cultivation.In the middle and adjacent towns in the Southern section of the plain and in the reaches of Daxing International Airport,the ecological restoration model should be water diversion,water replenishment,artificial wetlands,anti-seepage,seepage reduction,shallow ponds,plant cultivation,ecological protection,and shoreline slope ecological protection;The ecological restoration model of other general river sections should be mechanical obstacle clearance,sand pit landfill,plant planting and coastal slope ecological protection.