Research On Ecosystem Health Evaluation And Development Trend Of Fuhe River Basin Based On PSR And SD Model

The construction of ecological civilization is an important cornerstone of regional development.Ecosystem health evaluation is an important part of the construction of ecological civilization.The development of watershed ecosystem health evaluation is of positive significance to the sustainable development and comprehensive management of the watershed.The Fuhe River Basin(Fuzhou Section)is the first batch of national pilot areas for comprehensive management and sustainable development of water environment in the river basin.It recognizes the achievements in the coordinated promotion of ecological civilization in the Fuhe River Basin,and aims to explore the protection,governance and development of a river basin with good water quality in the central region.Model,form a spatial pattern,industrial structure,production method,and lifestyle that conserve resources and protect the environment,and strive to explore a development path that can be replicated and promoted.Carrying out research on the ecological system health of the Fuhe River Basin will provide theoretical basis and decision-making services for exploring the planning,management and protection of small watersheds and regional sustainable development.In this study,the Fuhe River Basin(Fuzhou Section)was used as the research object,and the Pressure-State-Response(PSR)model was used to construct the Fuhe River Basin ecosystem health evaluation index system,and the spatial and temporal evolution of the ecosystem health in the study area from 2010 to 2018 and the changes of obstacle factors were analyzed.On this basis,the system dynamics theory and methods are used to construct the Fuhe River Basin ecosystem health system dynamics(SD)model,to simulate the development trend of the ecological system health in the study area,and to promote the sustainable development of the Fuhe River Basin according to the research results.Countermeasures and suggestions for the construction of ecological civilization.The main research conclusions are:(1)The ecosystem health of the study area has maintained a steady upward trend.During the study period,the stress index changed from 0.584 to 0.636,maintaining a relatively healthy state;the state index changed from 0.446 to 0.448,maintaining a general state of health;the response index changed from 0.505 to 0.563,changing from relatively healthy to healthy.(2)There are obvious differences in the ecosystem health status of the counties in the basin.From an overall point of view,the areas with relatively good ecosystem health are mainly in Guangchang County and Lichuan County in the upper reaches of the Fuhe River,because of strong local water source protection measures,large forest coverage and dense water networks;and the ecosystem health status The relatively poor areas are mainly located in Dongxiang District and Chongren County in the middle reaches of the Fuhe River Basin,which are mainly related to the dense population and expansion of construction land.(3)The ecosystem health of the study area presents a "south-north" spatial pattern distribution.Based on the standard deviation ellipse analysis,the geometric center of the standard deviation ellipse is slightly offset,showing a change in the direction of northwest and then south.It shows that the southern region has a strong pulling force on the standard deviation ellipse.From the perspective of the change of the ellipse,the standardized ellipse rotates counterclockwise,deflection from "Northeast-Southwest" to "North-South",indicating that the north-south direction has greater influence on the deflection of the ellipse.(4)The degree of barriers to the criterion level varies among counties.Through the analysis of obstacles,it is concluded that between 2010 and 2018,Linchuan District,Dongxiang District,Nancheng County,Lichuan County,Nanfeng County,and Chongren County were greatly affected by pressure layer barriers.The main obstacle factors were land use intensity and GDP per ten thousand yuan Energy consumption and other indicators.Yihuang County,Jinxi County,Zixi County and Guangchang County are mainly affected by the barrier factors of the response criteria.The main barrier factors are the harmless treatment rate of domestic waste and the green coverage rate of built-up areas.Le’an County is greatly affected by the state-level barriers.The main barriers are GDP per capita and population density.(5)According to the simulation results,the total GDP of the study area can reach259.308 billion yuan by 2030,showing a steady upward trend.The total population of the study area is expected to reach 4,395,850 by 2030,and will show a slow growth trend.The employment population structure has gradually changed from "one,three,two" to "three,one,two".Energy consumption will reach 8,110,63 million tons by 2030.The total social water demand in 2030 will reach 146.567 million cubic meters.With the gradual increase in investment in water supply and energy,the tightness of resource supply has gradually eased.The area of arable land and forest decreased slightly,and the area of construction land and water area increased.With the gradual expansion of the industrial scale,the amount of wastewater discharged and treated will increase simultaneously,and the intensity of wastewater discharge will continue to decline.By 2030,the destruction of the ecological environment will continue to improve,and ecological health will gradually recover.