Objective This research explores the spatial distribution characteristics, supply-demand matching patterns, relationships, and optimization strategies of cultural ecosystem services (CES) in urban park green spaces. These efforts aim to enhance the efficiency of ecosystem services, promote spatial equity, and provide new perspectives and methodologies for studying CES in urban park green spaces.

Methods Using 222 park green spaces in the main urban area of Chengdu as research objects, the research divides the area into 500 m × 500 m grids for analysis. First, an evaluation indicator system and a supply-demand relationship model encompassing supply potential, supply opportunity, and resident demand dimensions are constructed to analyze the matching relationship and spatial distribution characteristics of CES. Second, the research applies a coupling coordination model to assess the coupling and coordination levels of CES supply and demand of urban park green spaces. Finally, based on the combined results of the supply-demand matching evaluation and the coupling coordination analysis, optimization strategies for CES in Chengdu’s park green spaces are proposed at the subarea level.

Results The comprehensive supply level of CES in Chengdu’s park green spaces exhibits a cluster distribution pattern that is “higher in the south, and lower in the north”, with high-value areas concentrated in the central and southwestern parts of the main urban area, and low-value areas mainly distributed in the northeastern part. Meanwhile, the comprehensive demand level for CES displays an aggregated cluster distribution pattern, where high-demand zones are located in the central and southern part of the main urban area with high population density, strong human activity, intensive urban development, and well-developed facilities, while low-demand zones are found in the less densely populated and developed northeastern part. The supply-demand matching patterns are predominantly high supply-high demand and low supply-low demand, reflecting a low-level equilibrium with significant supply gaps; zones characterized by high supply-high demand and high supply-low demand are mainly found in the central and southwestern parts of the main urban area, whereas whose with low supply and low demand are primarily located on the periphery of the main urban area. Additionally, the coupling coordination degree of supply and demand exhibits a decreasing trend from the city center to the periphery. Overall, the coupling coordination degree is suboptimal, with the zones featuring the highest coordination degree only reaching a barely coordinated level. Specifically, the barely coordinated zones are primarily concentrated in the central part of the main urban area. Overall, the spatial distribution of the supply-demand matching for CES of park green space in the main urban area of Chengdu exhibits a characteristic of being higher in the southwest and lower in the northeast. The distribution of mismatched zones is relatively scattered, and the coupling coordination is generally at a low level. The spatial differentiation of supply-demand coordination relationships is evident within the main urban area.

Conclusion By overlaying the results of supply-demand matching types with coupling coordination levels, the research categorizes the service ranges of all park green spaces into three functional zones: Efficient zones, transitional zones, potential zones, and proposes optimization strategies accordingly. Efficient zones, primarily located in the central and southern parts of Chengdu’s main urban area, are characterized by high supply and high demand with coupling coordination levels ranging from mild imbalance to barely coordinated. To enhance efficiency, it is recommended to construct a hierarchical and continuous green space network to improve connectivity and systematic integration, thus improving the supply efficiency to benefit surrounding under-supplied zones. Transitional zones, situated on the fringes of park green space service ranges, are dominated by low supply and high demand and low supply and low demand, with coupling coordination levels ranging from severe imbalance to moderate imbalance, for which the optimization strategies include increasing the supply of park green space through urban micro-renewal measures in densely populated areas and optimizing public service facilities in less developed peripheral areas to improve the efficiency of interaction with nearby parks. Potential zones, located mainly in the southern and northeastern parts of the main urban area, exhibit high supply-low demand characteristics with coupling coordination levels ranging from severe imbalance to moderate imbalance, for which the optimization strategies focus on expanding service coverage and enhancing supply spillover effects by developing these zones as ecological education hubs and improving accessibility through transportation infrastructure. These findings provide a basis for improving the efficiency of CES, advancing the planning and management of urban park green space, and ensuring environmental equity.