Impacts of urban expansion patterns on ecosystem service balance and equity: A case study of Yunnan's border counties, China

Understanding and addressing the challenges of ecosystem service supply-demand (ESSD) balance and spatial equity are critical for promoting sustainable development and achieving regional coordination in border regions. This study focuses on 25 border counties in Yunnan Province, examining the supply-demand dynamics of ecosystem services (ESs) under different urban expansion patterns. It employs the Gini coefficient to quantify the equity of ESSD, highlighting differences in ESSD balance and equity between port and non-port counties. The findings indicate that border counties generally exhibit an ESSD surplus, but counties with higher urbanization levels have lower ecosystem service (ES) supply. Regarding spatial equity, port counties consistently show lower equity in ES distribution compared to non-port counties, suggesting significant ecological equity challenges in port counties amid economic growth pursuits. Furthermore, certain urban expansion patterns, particularly adjacent-type expansion (e.g., infilling and edge-expansion), exacerbate ESSD imbalances and reduce spatial equity. Analysis of driving factors reveals that socioeconomic factors, especially increased urbanization rates, significantly negatively affect both the supply and equity of ESs. Based on these findings, the study recommends adopting tailored urban planning strategies that account for local characteristics, balancing the dual objectives of ecological conservation and sustainable development. • The urbanization process of border port and non-port counties differed. • The ESSD equity in port counties is significantly lower than in non-port counties. • Adjacent-type expansion worsens key ESSD balance and spatial equity loss. • Proposed targeted policy advice for sustainable development in border regions.