Quantification and Flow Simulation of Ecosystem Service Supply and Demand in the Yellow River Delta High-Efficiency Eco-Economic Zone

The identification of supply and demand areas for ecosystem services (ES) and the simulation of ES flows are essential for optimizing ESs to achieve socio-economic sustainable development. However, the selection of investigation methods and simulation model remains a persistent challenge. This study selected the Yellow River Delta High-Efficiency Eco-Economic Zone in China as the case study area and assessed the habitat quality and carbon sequestration services for 2000, 2010, and 2020. The quantile regression method was employed to quantify the impacts of land use structure on balancing the supply and demand of ESs. The minimum cumulative resistance model, circuit corridor model, and wind direction model were utilized to analyze changes in flux and flow direction of ESs' supply and demand. The results demonstrated that the following: (1) the supply of ESs generally increased, with a significant rise in demand for carbon sequestration service and a declining trend in habitat quality service demand. (2) A clear spatial mismatch existed between the supply and demand of ESs. (3) The impact of land use structure on the balance of ES supply and demand is complex. (4) Habitat quality and carbon sequestration services exhibited distinct spatial clustering patterns. (5) The flow patterns of habitat quality service were characterized by specific supply and demand areas, with corridors and pinch points indicating the flow paths and potential barriers; not all demand areas for carbon sequestration service can be satisfied due to variations in service levels and geographical distance. The innovation of this study lies in the following aspects: (1) it acknowledges the uniqueness of ecosystem services, with a focus on assessing habitat quality and carbon sequestration services; (2) it precisely quantifies the flow of ecosystem services, analyzes the spatial dynamics of service flows, and investigates the impact of changes in land-use structure on these flows; (3) it strengthens the correlation between the supply and demand of ecosystem services and socio-economic activities, uncovers the contradictions between supply and demand along with their underlying causes, and proposes effective strategies for resolution. The findings can provide theoretical and methodological references for the optimization of ES.