Research On Health Evaluation Of Rivers In Mountainous Cities In Southwest China

Healthy rivers have a vital impact on human survival and sustainable development,and river health is mainly reflected in whether it can properly exert its natural ecological functions and social service functions.With the acceleration of urbanization in recent years,human activities have become more and more disruptive to natural rivers.River systems have been adversely affected,and river health conditions have become worse and worse,making rivers unable to perform their various functions.Therefore,the evaluation of the current river health status has become a hot issue.Although the mountainous cities in southwest China are in the economically underdeveloped areas of China,in recent years,the economic development of the region has grown rapidly,and the scale of cities has continued to expand.Under such economic growth,the health of the urban rivers has been seriously threatened.The evaluation of urban rivers for health is of great significance.The main research contents and research results of this paper are as follows:(1)Based on the research status of river health evaluation at home and abroad,this paper analyzes the characteristics of urban rivers in southwest mountainous areas,clarifies the concept and connotation of river health,and analyzes the influencing factors,and selects the best reachable state as the baseline status of the health assessment of urban rivers in southwestern mountainous areas.(2)Based on the basic theory of urban river health in the southwest mountainous area,the Simao River in Pu’er City was selected as the research object of this paper.The current situation of the research area was investigated and analyzed.The basic situation of the research area,the basic situation of the river,the water resources,the waterfront coastline,the water pollution situation,water environment status and water ecological situation are summarized and analyzed,and the basic work for the subsequent selection of evaluation indicators is made.(3)Exploring the evaluation scale of urban river health evaluation research in the southwest mountainous area,and divide the river health status into five levels: “ideal state”,“healthy”,“sub-healthy”,“unhealthy” and “morbid”.According to the characteristics of urban rivers,research areas and evaluation indicators in southwestern mountainous areas,according to the target layer,criterion layer,sub-criteria layer and index layer hierarchy,20 evaluation indicators closely related to the health status of urban rivers in southwestern mountainous areas were selected and established.The urban river health evaluation index system in the southwest mountainous area determines the meaning,calculation method and evaluation criteria of each indicator.On the basis of comparative analysis of various index weight calculation methods,it is determined that the weight of the index is calculated by using the analytic hierarchy process.Two river health assessment methods widely used at home and abroad,namely the comprehensive index evaluation method and the fuzzy comprehensive evaluation method,are selected as the evaluation methods of this paper,which are easy to compare with each other to ensure the accuracy of the evaluation results.(4)Taking the Simao River in Pu’er City as an example,the health evaluation system of the city river in the southwest mountainous area established in this paper is used to evaluate the health of Simao River.The results show that the Simao River as a whole is a “sub-health” grade,and five river sections have been evaluated,one of which is “healthy” and the other four are “sub-health”.According to the analysis of the evaluation results,the suggestions for the management and governance of urban rivers in the southwest mountainous areas are put forward.