Trade-offs and synergies relationships of ecosystem services and their socio-ecological driving factors under different spatial scales in Shaoguan City, Guangdong, China.

Ecosystem services refer to the benefits that human obtain from natural ecosystems. Different ecosystem services are generated by the combination of social-ecological driving factors, and exhibit different spatial patterns across scales. The complex relationships and driving mechanisms among ecosystem services under different spatial scales remain unclear. With Shaoguan City from Guangdong Province as the study area, we analyzed the spatial patterns and relationships of four ecosystem services and their trade-offs/synergies (TOSs), quantified their responses to seven social-ecological drivers at the kilometer grid scale and sub-watershed scale, and proposed regional ecologi-cal management and planning strategies for cross-scale sustainable development. The results showed that the spatial distribution of ecosystem services in Shaoguan City exhibited spatial clustering and cross-scale variations. Habitat quality, water yield, and carbon storage exhibited similar spatial distribution pattern. High supply was mainly distributed in mountainous areas in the east, north, west, and south, while weak supply was distributed in plain areas in the central, northwest, south and northeast. In addition, the spatial clustering of these services intensified with increasing spatial scale. Ecosystem services displayed synergistic relationships at both spatial scales, and the intensity of the synergy changed with scale. At both the kilometer grid and sub-watershed scale, the primary drivers for ecosystem services were the normalized vegetation index and digital elevation model. The main driver for TOSs was the mean annual temperature at the kilometer grid scale, while it was the mean annual evapotranspiration at the sub-watershed scale. Based on the supply levels of ecosystem services, the study area could be divided into five distinct ecosystem service bundles, i.e., mountain ecological balance zone, forest ecological conservation zone, urban forest maintenance zone, ecologically sensitive zone, and ecological risk zone. All bundles exhibited both spatial heterogeneity and cross-scale variations. We integrated the cross-scale variations of four representative ecosystem services and their complex interactions and driving mechanisms in Shaoguan City into spatial planning to facilitate the sustainable ecosystem management across multiple scales, which could offer valuable references for the construction of ecological civilization in other regions.