The spatial spillover effects of ecosystem services: A case study in Yangtze River economic belt in China

• Inter-regional ecosystem service flows have obvious directional changes. • The spatial network in Yangtze River Economic Belt has spatial spillover effect. • Socioeconomic activities and nature resource are vital for ecosystem service flow. Spatial characteristics and geographical scales are crucial factors influencing the functioning of ecosystem services (ESs), especially the spatial flows that transcend territorial boundaries. A comprehensive understanding of the spatiotemporal evolution of these spatial spillover effects enriches our knowledge on the distribution and temporal dynamics of ecosystem service functions. By examining the spatiotemporal evolution of ecosystem service flow effects of the Yangtze River Economic Belt (YREB), the study offers scientific evidence underpinning the sustainable development of ESs among different regions. To this end, this study undertook the computation of ecosystem service values (ESV) and utilized an improved gravitational model to establish the ESV spatial correlation network (SCN) in the YREB. Subsequently, social network analysis (SNA) was employed to examine the spatiotemporal evolution of the ESV-SCN. Finally, an analytical framework was constructed to scrutinize the factors that influence the ESV-SCN under the influences of both natural and socio-economic factors. The results suggest: 1) Between the years 1990 and 2020, ESV within the YREB exhibited substantial spatial correlations and overflow effects, with a notable 3.49% increase in network density; 2) The hierarchical structure of the ESV-SCN witnessed a 44.51% decline, while network efficiency witnessed an 8.47% increase. Moreover, network accessibility strengthened, and the discernible presence of multiple overlapping effects contributed to heightened stability; 3) Both within and between various sectors of the ESV-SCN, substantial linkages and cascading effects were noted. The spatiotemporal evolution of the SCN exhibited distinct hierarchical and clustering patterns, with the complexity of the network structure steadily augmenting; 4) Natural factors such as temperature, precipitation, the proportion of forest land, alongside socio-economic factors like the level of economic development and innovation, all played indispensable roles in shaping and nurturing the ESV spatial correlation networks.