Assessment Of Ecosystem Services In The Source Area Of The Yellow River And Future Multi-scenario Simulation

The sustainable development of ecosystem services is the basis and key to maintain regional and global sustainable development.The source area of the Yellow River is located in the hinterland of the Qinghai-Tibet Plateau,and its ecological environment is fragile.It is an important water conservation area and biodiversity conservation area in the Yellow River basin.In recent decades,with the gradual acceleration of global climate change and the increasing intensity of human development activities,the stability of various ecosystem services in the source area of the Yellow River is being destroyed.According to relevant data,the land use change in the source area of the Yellow River is significant,the ecological environment security is facing challenges,and many ecosystem services are showing an unsustainable trend.In view of this,it is urgent to carry out the assessment of ecosystem services in the source area of the Yellow River and the future multi-scene simulation study,clarify the response relationship between land use change and ecosystem services,and provide certain scientific reference for the formulation of ecological protection policies and the rational allocation of land resources in the source area of the Yellow River.Based on the land use data of the source area of the Yellow River in 2000,2010 and 2020,this paper first analyzes its spatiotemporal,transfer and landscape pattern changes.Select the most widely used ecosystem service evaluation model,In VEST model,to evaluate the three typical ecosystem services of carbon storage,habitat quality and water yield in the source area of the Yellow River from 2000 to 2020,discuss the change law of ecological services in the region and its response to land use change,and finally simulate and predict the multi-scene land use pattern and ecosystem service function change in the study area in 2040 by combining with Geo SOS-FLUS model,Based on the change characteristics of land use and ecosystem services in the future,the suggestions and directions for ecological protection in the source area of the Yellow River are discussed.The main conclusions are as follows:(1)Grassland is the main land type in the source area of the Yellow River,with the highest proportion of medium coverage grassland area,reaching 33% of the total area of the source area of the Yellow River.From 2000 to 2020,affected by the implementation of ecological protection policies,the land use structure in the source area of the Yellow River was significantly optimized,the area of grassland and wetland was significantly increased,and the flow of land use types was frequent,among which the most significant conversion feature was the significant reduction of unused land and most of it was converted into low-coverage grassland,resulting in the improvement of the overall ecological environment.The increase of construction land was significant,with an increase of 237.84% in 20 years,and most of the increased area came from the encroachment of grassland.(2)From 2000 to 2020,the spatial distribution of carbon storage,habitat quality and water yield in the source area of the Yellow River showed a gradual increase from northwest to southeast,and various ecosystem services showed strong spatial heterogeneity.Grassland,forest land and wetland provide strong ecosystem services.Affected by the implementation of ecological protection policies in the past 20 years,the carbon storage,average habitat quality and water yield in the source area of the Yellow River have increased.Among the nine types of land use in the source area of the Yellow River,the highest proportion of ecosystem services are provided by grassland of different coverage.The area change of grassland and land transfer characteristics are the key factors affecting the sustainable development of ecosystem services in the source area of the Yellow River.(3)The above research results show that as a typical grassland ecosystem,the stability of ecological security and the sustainable development of ecosystem services in the source area of the Yellow River need to pay special attention to the change of grassland status.The governance effect in the past 20 years has been remarkable,but at the same time,the relationship between ecological protection and pastoral urbanization should be coordinated to achieve the coordinated development of ecology and economy.The above research results indicate that as a typical grassland ecosystem,the stability of ecological security and the sustainable development of ecosystem services in the Yellow River source area require special attention to the changes in its grassland status.The governance achievements of the past 20 years have been significant,but at the same time,the relationship between ecological protection and urbanization in pastoral areas should be coordinated to achieve coordinated development of ecology and economy.