Spatial pattern evolution of territorial space and its effects on ecological response in the Yellow River Basin during 2000-2020

Abstract: As an important economic zone and ecological barrier in China, the rapid urbanization and industrialization of the Yellow River Basin (YRB) have led to drastic changes in territory space, significantly affecting the value and function of ecosystem services. Thus, the scientific revelation of ecosystem service value (ESV) response laws is an essential part of building a high-quality territorial spatial system. To this end, a two-tiered system of spatial classification of the national territory has been constructed from the perspective of "production-living-ecological" space. Details of the procedure are as follows. Firstly, based on the land use/cover data of the YRB from 2000 to 2020, the territory spatial transfer matrix was used to analyze the evolution process of territory spatial patterns within the natural boundary of the basin. Then, the crop yield data and NDVI data during the study period were used to revise the equivalence factor for ESV in the YRB. The spatiotemporal characteristics of ESV were revealed at the whole basin, secondary watershed and grid scales by using the modified ESV evaluation model and ArcGIS spatial analysis. Finally, the ESV map method was used to reveal the response pattern of ESV change in the YRB. The results show that: 1) The territory space type of the YRB was mainly dominated by ecological space from 2000 to 2020. In the first-level space, the production space continued to decrease, the living space gradually increased, and the ecological space fluctuated was relatively stable. Except for the agricultural production space and other ecological space decreased, other spaces were on the rise. In terms of transition types, the territory spatial transitions of the YRB were mainly based on the mutual transformation between grassland ecological space and agricultural production space, other ecological space and forestland ecological space, which were mainly distributed in the middle and upper reaches of the YRB. 2) During 2000-2020, the ESV showed an overall upward trend, changing from 10 976.59 × 108 yuan in 2000 to 11 210.96 × 108 yuan in 2020. Grassland ecological space and forestland ecological space made the greatest contribution to the total ESV. The functional types of ecosystem services were mainly supporting services and regulating services. The change range of individual ecosystem service value was small, and the structure was basically stable. In terms of spatial distribution, the ESV showed the spatial pattern of "the highest in the central and southwest, the higher in the northeast and southeast, and the lowest in the northwest", and the number of areas with significant increase gradually increased. 3) The ecological appreciation zones were widely distributed and scattered, with the conversion of other ecological spaces into grassland ecological spaces, agricultural production spaces into ecological spaces, and grassland ecological spaces into water ecological spaces and forestland ecological spaces. The ecological impairment zones were gradually expanding in scope, with the conversion of ecological spaces to agricultural production spaces and grassland ecological spaces to other ecological spaces. The research results can provide reference and basis for land space optimization and ecological civilization construction in the YRB.