Ecosystem Service Assessment And Multi-scenario Prediction In The Shaanxi Section Of The Qinling Mountains

Ecosystem service is the support and guarantee that ecosystem provides for human production and life.As an important ecological security barrier and water culvert areas in our country,Qinling mountain provides many ecosystem services of regulating climate,conservation soil and water,conservation water source,conservation of biodiversity,etc.It has an important position in natural ecosystem in our country.How to further optimize the spatial development pattern of the Shaanxi section of the Qinling Mountains,enhance the stability of the Qinling Mountains ecosystem,and improve the function of the Qinling Mountains ecosystem will become the next focus of the sustainable restoration of the ecological environment of the Qinling Mountains.Based on this study,the spatial and temporal characteristics of ecosystem services and their spatial and temporal variability were investigated.The synergistic relationships of ecosystem service trade-offs were identified.The dominant drivers were identified using the geodetector model.And their driving mechanisms were revealed.The study then combined the PLUS and In VEST models to predict land use change,ecosystem services and their trade-off synergies in the Shaanxi section of the Qinling Mountains in 2030.The main conclusions are as follows:(1)The forested area of Shaanxi section of the Qinling Mountains accounts for about 41%of the total area of the whole region.With good overall forest cover,the forested area has increased by 279.53 hm~2 in 20years,while the arable area has the most decreasing of 321.36 hm~2.Various types of land use change frequently.Especially the conversion between grassland,forested land and arable land and the conversion of arable land to construction land are the most significant.Before 2015,the growth rate of land for construction was the highest.Then,the area of forest land and grassland started to rebound due to the strict ecological protection policy,the continuous promotion of measures to return farmland to forest and grass,the continuous improvement of the"five disorders"of the Qinling Mountains and the restoration and treatment of the ecological environment of mines.The spatial distribution of land use types in the Shaanxi section of the Qinling Mountains has obvious vertical divergence.Grassland,arable land,construction land and water areas show a trend of increasing and then decreasing in elevation,while the distribution of forest land mainly increases with increasing elevation.(2)Water production,carbon storage and habitat quality ecosystem services show a fluctuating upward trend between 2000 and 2020,while soil retention decreases.In the 20 years,spatially changes of ecosystem services were not significant.Meanwhile,ecosystem services showed significant spatial heterogeneity.Ecosystem services differed significantly between land types depending on their vegetation cover and land use patterns.It can be found through geographic detectors that the contribution rate of natural factors to various ecosystem services is relatively high,especially that of land use type,evapotranspiration and elevation.Through the analysis of interactive factor detection,the results show that the influence of two driving factors on the spatial differentiation of ecosystem services is higher than that of a single driving factor.(3)From 2000 to 2020,the tradeoffs and synergies of the four ecosystem services in the Shaanxi section of the Qinling Mountains remained stable,but the clustering distribution of tradeoff synergies showed spatial heterogeneity between years.Soil conservation and water yield,habitat quality and carbon storage showed different degrees of synergistic relationship in each study period,while water yield and carbon storage and habitat quality showed different degrees of tradeoff relationship in each study period.(4)Under the natural development scenario,the area increase of construction land is higher than the other two scenarios.Under the ecological protection scenario,the area of forest land,grassland and water area increased the most,while the area of cultivated land decreased the most.Under the cultivated land protection scenario,the area of cultivated land increased the most,while the area of forest land and construction land decreased the most.Under the ecological protection scenario,the integrated ecosystem service index was the highest,while under the cultivated land protection scenario,it was the lowest.This indicates that the ecological protection scenario is more conducive to the development of ecosystem service function in Shaanxi section of Qinling Mountains.