Research On Spatio-Temporal Changes And Influencing Factors Of Ecosystem Service Functions Of The Yellow River Basin

The Yellow River Basin is an important ecological barrier and economic zone in China,which provides various ecosystem service functions,so it is of far-reaching significance to carry out research on ecosystem service functions in the Yellow River Basin.Based on the analysis of land use dynamics in the Yellow River Basin in 2000,2005,2010,2015 and 2020,combined with meteorological,soil and elevation data,the thesis uses the InVEST model to quantitatively analyze the ecosystem service functions of the river basin,and explores the temporal and spatial evolution of ecosystem service functions of each ecosystem service function and the status of ecosystem service functions of different land types.The spatial distribution and spatial aggregation characteristics of various ecosystem service functions were studied through cluster analysis and functional zoning.Geographic detectors were used to explore the intrinsic mechanisms of natural factors,human factors and ecosystem services.The main conclusions of this article are as follows.(1)There are obvious spatial and temporal differences in land use in the Yellow River Basin.Cultivated land is the most widely distributed and relatively scattered,with increased fragmentation.Grassland and unused land are relatively concentrated in the Qinghai,Sichuan,and Inner Mongolia regions of the basin.Construction land is mostly distributed in the developed areas downstream of the basin,such as Zhengzhou,Jinan,and Xi’an,and its quantity and radius are increasing significantly.The reduced cultivated land and grassland mainly flow into construction land.(2)The overall ecological environment of the Yellow River Basin is improving.Except for Carbon storage,Water conservation,Soil conservation,and Habitat quality have all improved significantly,with large fluctuations occurring in 2015.The ecosystem services and hot spots of the basin have obvious spatial distribution differences.From south to north,the water conservation capacity gradually decreased,and the hot spots gradually transitioned to the cold spot area,and the overall distribution was relatively concentrated.Soil conservation and Water conservation have certain spatial similarities,showing a high,low,and north-south arrangement.The distribution of the hot spots is relatively scattered,while the cold spots are relatively concentrated.Carbon storage and Habitat quality have spatial similarities,showing a distribution characterized by alternating hot and cold spots.In terms of land-use differences,forest land has the best overall ecosystem service,particularly in Water conservation,Soil conservation,and Carbon storage,and the water’s habitat suitability is the best;grassland creates the greatest ecosystem service value in the basin,with the highest contributions to Water conservation,Soil conservation,and Habitat quality,and the contribution of Carbon storage to dryland is the highest.(3)From the results of functional zoning,the overall performance of the watershed is good.From the results of single-function zoning,the functional areas of water conservation,carbon storage and habitat quality were more than the non-functional areas,while the non-functional areas of soil conservation accounted for 68.76%,and they were concentrated in the upper reaches of the watershed.From the results of composite function zoning,the area of the composite functional area is much more than that of the single functional area,and there is a clear boundary between the two,and the ecological environment south of the boundary is better than that of the north of the boundary,which corresponds to the distribution of land use types,and the ecological environment in the upper reaches of the watershed is also better,but it is inconsistent with the distribution of land use types.(4)Through the study of influencing factors,it can be concluded that land use status and average annual precipitation have the greatest impact on ecosystem services,and land use status is the decisive factor for carbon storage and Habitat quality.Other factors that have a high degree of influence and a positive effect on ecosystem services have a strong spatial correlation with them;for example,in a certain region,the vegetation coverage index and precipitation erosion factor have high spatial similarity with water conservation and soil conservation.For different functions,the same factor performs differently;for the same function,different influencing factors have significant differences.Among which land use status and natural factors both have significant differences,as do other factors.The q value of the interaction between each functional influencing factor is greater than the q value of each single factor,indicating that the interaction between each factor has a greater impact on the ecosystem service than a single factor.