Dynamic of Land Use and Associated Ecosystem Service Value in the Chengdu–Chongqing Urban Agglomeration, China

Understanding the long-term land use changes in the Chengdu–Chongqing urban agglomeration, a vital element of the Yangtze River Economic Belt and a key economic growth center in western China, can offer scientific basis and policy direction for improving regional ecosystem service values (ESVs), environmental conservation, and sustainable development. This study investigated the features connected to land use change, changes in landscape patterns, and variations in ESV across this region by means of time series of remote sensing and socio-economic data from 1990 to 2020. Additionally, the correlations between landscape pattern indices and ESV were examined. The findings indicated that: (1) cultivated land and grassland in the Chengdu–Chongqing urban agglomeration exhibited a declining trend, while forest, water, and construction land demonstrated increasing trends; (2) human activities significantly affected the Chengdu–Chongqing urban agglomeration, resulting in severe landscape fragmentation, heterogeneity, complexity of types, and patch separation, although the predominant patch types maintained strong connectivity; (3) the ESV of the Chengdu–Chongqing urban agglomeration initially decreased, reaching a minimum of CNY 5.017 billion in 2000, and subsequently rose again. Forest land accounted for approximately 69% of the overall ESV in the region over the preceding decades. The policy of reverting farmland to forest, the establishment of wetland parks, and the increased awareness of environmental protection have led to notable alterations in land use types and landscape patterns within the Chengdu–Chongqing urban agglomeration, which can significantly improve the regional ecosystem service value; however, the extent of influence and trends among various landscape indices are disparate.