Simulating the impact of urban expansion on ecosystem services in Chinese urban agglomerations: A multi-scenario perspective

Urban agglomerations (UAs) are the most active areas of urban land expansion. The encroachment of urban land on large-scale ecological land has caused severe ecological problems and threatens the ecological sustainability of UAs. Understanding the characteristics of multi-scenario urban land expansion and its impacts on ecosystem services (ESs) in UAs can provide guidance for formulating ecologically sustainable management and control policies in UAs. However, few studies have simulated the characteristics of multi-scenario urban expansion and determined its impacts on ESs in Chinese UAs. In this study, we used a patch-generating land use simulation (PLUS) model and the benefit transfer method to conduct a multi-scenario simulation of urban land expansion in Chinese UAs in 2030 and measure its impacts on ESs. The simulation indicates that urban land continued to expand and expanded most severely under an urban development scenario. In the future, under an ecological protection scenario, ESs would be maintained at their highest levels. In general, the global Moran's I indices of the ESs and urban expansion were negative at the 0.001 significance level, indicating that ESs and urban expansion in Chinese UAs were strongly spatially concentrated. The impacts of urban expansion on the ESs varied among the UAs. In national and regional UAs, ESs were affected negatively by patch density (PD) and percentage of like adjacencies (PLADJ), whereas the loss of ESs in local UAs was not only affected by PD and PLADJ, but also by the proportion of urban land. These findings provide effective guidance for improving ESs, urban development planning, and high-quality development in Chinese UAs.