Evaluation and Prediction of Water Environment Carrying Capacity in Large-scale Rivers Based on Natural Elements
The water environmental carrying capacity is an important indicator for protecting the water environment,used for the rational planning and management of water resources to ensure their sustainable utilization.In order to explore a more systematic and comprehensive evaluation index system for water environmental carrying capacity applicable to large rivers,this study selects the main stream of the Yangtze River as the research object.Four aspects,namely,"natural factors,water resources,ecological environment,and socio-economy,"are taken as indicator layers,and a total of 25 specific indicators are selected.The improved principal component analysis method is used to evaluate the spatiotemporal changes in the water environmental carrying capacity of the main stream of the Yangtze River.Furthermore,the ARIMA model is used to predict the development of the water environmental carrying capacity for the next three years.The results show that the comprehensive indicator score has an overall upward trend over time.The comprehensive score gradually increases from-1.66 to 1.26,indicating an improvement from Grade IV(poor)to Grade I(excellent).It is projected to continue with a slight upward trend over the next three years.
Yangtze River main streamWater environment carrying capacityPrincipal component analysisTemporal and spatial change characteristicsModel prediction