Research On The Assessment For Health Degree Of Urban Rivers In Coastal Plain

As the carrier of human survival,rivers play a decisive role in the transfer of matter and energy on the earth.Healthy river system is the basis for normal development of ecological functions and social service functions.However,with the rapid development of society and the ever-increasing scale of cities,human interference in rivers has become more and more severe.The stability of river systems has gradually declined,and the health status of rivers is not optimistic.Therefore,how to scientifically and accurately characterize and evaluate the health of rivers has become a hot issue that people are concerned about.The coastal plain urban belt in the eastern part of China is the region with the most developed economy,the most densely populated and the highest level of urbanization in China.It is of great significance to carry out the assessment of river health.Based on the river health assessment studies at home and abroad,this paper analyzes the characteristics of urban rivers in coastal plains,defines the concept of urban river health in coastal plains,analyzes the health connotation of urban rivers in coastal plains and its influencing factors,and selects the most achievable The state of goodness is the baseline condition for the evaluation of the health of urban rivers in coastal plains.To evaluate the evaluation scales,evaluation methods and evaluation principles for evaluation of the health of urban rivers in the coastal plains,and to classify the urban river health in the coastal plains as "ideal","healthy","sub-healthy" and "unhealthy"."Ill" five levels,analyze the meaning of each level.According to the characteristics of urban rivers in the coastal plains and the principle of selection of evaluation indicators,according to the target layer,attribute layer,criterion layer,and index layer,21 evaluation indicators that are closely related to the urban plains of the coastal plains are selected to construct the urban river health of the coastal plains.Degree evaluation index system,classification criteria.On the basis of analyzing the advantages and disadvantages of various river health evaluation methods,combining the characteristics of urban rivers in the coastal plains and the operability of the indicator data,AHP and Matter Element Analysis were selected as the mathematical model for this study.First,the AHP was used to calculate the weight of each evaluation index,and then the matter-element analysis method was used to evaluate the health of the river.Select three city rivers of Sheyang,Doualong,and Huangsha in Yancheng City as the research object,use the analytic hierarchy process to calculate the weight of each evaluation index of three rivers,and use the matter-element analysis method to evaluate the health of the three rivers.The evaluation results showed that the health of the rivers of Sheyang River,Doulong Harbor and Huangsha Port of Yancheng City are all changing to the sub-health level.According to the results of the evaluation,the possible problems in river management were analyzed,combined with the characteristics of urban rivers in coastal plains,river health improvement measures and recommendations were proposed.