Impact of Land Use Change on Carbon Storage and Habitat Quality: A Comparison of the Guangdong–Hong Kong–Macao Greater Bay Area and the Yangtze River Delta

The Guangdong–Hong Kong–Macao Greater Bay Area (GBA) and the Yangtze River Delta (YRD) are key economic growth poles in China, playing a critical role in driving national economic development and facilitating international exchanges in commerce, culture, and ecology. However, rapid urbanization and industrialization have exerted considerable pressure on regional environments. In this study, we first assessed the dynamics of carbon storage (CS) and habitat quality (HQ) in the GBA and the YRD from 2000 to 2020 using the InVEST model and ArcGIS software, systematically analyzing their spatiotemporal changes and underlying driving mechanisms. Subsequently, we employed the PLUS model to predict land use changes by 2030 and evaluate their potential impacts on CS and HQ. The results indicate that: (1) Both regions have experienced increases in construction land and declines in cropland. (2) Between 2000 and 2020, CS in the GBA decreased by 33.65 × 106 t and HQ declined by 0.0833, whereas in the YRD, CS decreased by 15.35 × 106 t and HQ dropped by 0.0504. (3) By 2030, CS in the GBA is projected to decline further by 4.08%, with HQ decreasing to 0.4777, while in the YRD, CS is expected to fall by 2.71% and HQ decrease to 0.4115. (4) The spatial differentiation of CS and HQ in the GBA is primarily driven by anthropogenic processes, whereas in the YRD it is mainly constrained by natural factors such as topography. This study highlights the importance of understanding the spatiotemporal dynamics of CS and HQ, which can help enhance ecosystem service functions, mitigate the impacts of climate change, and provide a scientific basis for regional sustainable development.