Assessment and multi-scenario simulation of ecosystem service values in Southwest China's mountainous and hilly region

The southwestern mountainous and hilly regions of China are vital ecological barriers upstream of the Yangtze River. Assessing and simulating changes in ecosystem service value (ESV) in this area is essential for ensuring sustainable ecological development. In this study, our purpose was to evaluate and simulate the spatial patterns as well as trends in the changes shown by the ESV in Yanting County, China, from 2020 to 2030 via a grid-scale using the equivalent factor method and the Markov-patch-generating land use simulation model. The results indicated that (1) from 2020 to 2030, forest, cultivated, and construction lands would be the main types of land use. (2) In 2030, the projected ESVs in Yanting County under the as-usual, low-carbon, and shared development scenarios were 5.31, 5.30, and 4.99 billion RMB, respectively. Compared to the 2020 ESV of Yanting County, the as-usual scenario and low-carbon scenario ESVs increased. The shared development scenario ESVs decreased. It reflects the contra-diction between urbanization, industrialization, agricultural production, and ecological protection in Yanting County. The spatial distribution of the ESVs of all three scenarios showed an agglomeration trend. (3) Given the background of national food security and carbon peaking and carbon neutrality, the setting of a low-carbon development scenario combined with a shared development scenario appears to be more suitable for the future development of Yanting County, which is conducive to the rational planning of land-use patterns and the sci-entific growth of ESV in Yanting County. This study underscores the critical importance of integrating ESVs in sustainable land-use planning and management, and provides a reference for the rational use of land resources, land spatial planning, and policy-making for ecological protection in Yanting County.