Assessment Of Water Environment Carrying Capacity In The Huangshui Watershed Based On The Coupling Of Ecosystem Services And Human Regulation

The water environment carrying capacity is the basis for the balance of water resource,people's life and social and economic development in the basin,and it is a comprehensive reflection of the management of water quality objectives and pollutant emission control.The evaluation of water environment carrying capacity of basins has important reference for the environmental management.It is practically significant to link the water environment carrying capacity with the socio-economic development and formulate coordinated development strategies.With the deveopment of sewage treatment plants and ecological wetland systems,artificial regulation plays an increasingly important role in water environmental carrying capacity.How to accurately locate and evaluate human regulation plays a key role.The study focuses on the lack of human regulation in current water environmental carrying capacity,based on the natural ecological service and human regulation ability,and analyzes the effect of natural ecosystem service and human regulation.From the perspective of "capacity augment" and "emission reduction",the index system of water environment carrying capacity is constructed,and the assessment model of water environment carrying capacity is proposed.As the research object of Huangshui Basin in Qinghai Province,the current status and improvement potential of water environment carrying capacity are assessed.Finally,based on the dynamics of SD system,an early warning model of water environment carrying capacity is constructed to simulate the change trend of water environment carrying capacity in the Huangshui Basin with four scenarios,in order to provide reference for the environmental management.Based on the above methods,the main conclusions of this study are as follows:(1)NH3-N and COD are the main indicators for the overloading of water environment carrying capacity in the Huangshui Basin,and the overload in the central region is the most serious.Human activities are the main source of overload;(2)COD is the highest potential for pollution reduction in the Huangshui Basin.The main way to improve is to enhance the collection and treatment rate of urban domestic sewage and the reuse rate of water,and regulate the using of chemical fertilizer;(3)Under the double-constrained scenario,the water environment can achieve continuous improvement of water environment,and controlling economic and social scale is critical to the improvement of water environment in the basin.The current water pollution control measures in the basin are not sufficient to cope with future environmental pressures,and there is still room for further improvement.