[Spatio-temporal Interactions Between "Spatial-economic-demographic" Carbon Strength and Ecosystem Services in the Shandong Section of the Yellow River Basin].

Exploring the spatio-temporal interactions between "spatial-economic-demographic" carbon strength and ecosystem services can effectively reveal the correlation and evolutionary differences between human social development and natural ecology under land-use change and provide a reference for comprehensive and high-quality development in the region under the goal of "double carbon." Taking the Shandong Section of the Yellow River Basin as an example, ecosystem services and carbon strengths of spatial, economic, and demographic dimensions were measured at the county scale from 2000 to 2020, the interaction elasticity index （IEI） was built to quantify the spatio-temporal interactions between each dimension's carbon strengths and ecosystem services, and the pattern of multi-dimensional interaction zoning and countermeasure suggestions were explored. The results showed that： ① The spatial and demographic carbon strengths were mainly changed positively, whereas the economic carbon strength was more negatively changed； the high values of the composite index of ecosystem services were concentrated in the east, and the index showed an overall increasing trend. ② The interaction between spatial and demographic carbon strength and ecosystem services was an ecological absolute decline relationship from 2005 to 2010, the ecological absolute increase relationship increased from 2010 to 2020, and the interaction between economic carbon strength and ecosystem services was dominated by an ecological invisible increase relationship. ③ The pattern of multi-dimensional interaction zoning was characterized by significant spatial and temporal variations, with the number of three-dimensional ideal interaction zones being the highest from 2010 to 2015, and two-dimensional undesirable interaction zones being the most widespread type of zoning. Multi-dimensional spatio-temporal interaction analysis could be used to explore the regional development situation from multiple dimensions, and the Shandong Section of the Yellow River Basin had more "spatial-demographic" undesirable interaction zones, the effect of green and low-carbon transformation was not obvious, and the enhancement of ecosystem services was poor and still needs to be improved.