[Spatio-temporal Scale Effects Analysis of Ecosystem Services Interactions in the Pearl River Delta Urban...

Accurately understanding ecosystem services （ESs） interactions across spatiotemporal scales is crucial for sustainable ecosystem management. We quantified the spatial heterogeneity of six ESs （i.e., water yield, soil retention, water purification, carbon sequestration, habitat quality, and food production） in the Pearl River Delta （PRD） from 2010 to 2022 using the InVEST model and socio-statistical methods. Based on this, the correlation coefficient method, geographically weighted regression model, and self-organizing feature mapping combined with K-means clustering analysis were employed to analyze the spatiotemporal scale effects of the interactions among these six ESs at three spatial scales, namely 1 km2 hexagonal grids, townships, and districts. The results showed that： ① The spatiotemporal heterogeneity of the six ESs in the PRD was significant. Except for soil retention, habitat quality, and food production, the other ESs showed an overall increasing trend over the past 12 years, and the overall spatial distribution pattern of ESs showed a gradient pattern of "increasing radiation from the central built-up area to the surrounding area." ② The interactions among paired ESs in the PRD were primarily synergistic, with most of the absolute values of the correlation coefficients reaching their lowest values in 2015. The interactive relationships and strengths between provisioning services and other ESs exhibited obvious scale variability and fluctuation, whereas the significant synergistic relationship between regulating and supporting services was less susceptible to scale changes. ③ Four types of ecosystem service bundles （ESBs） with different functions were identified at both the hexagonal grid, township, and district scales, including three of the same type of ESBs： ecological conservation bundle, agricultural ecology bundle, and urban ecological depletion bundle, along with three different types of ESBs： habitat quality bundle, urban ecological fragility bundle, and urban agricultural maintenance bundle. Transfers between these ESBs exhibited approximately symmetrical evolutionary characteristics over the last 12-year period. The findings can provide scientific references for regional ecological environment governance and ecosystem zoning management.