Investigating the impacts of multi-dimensional urbanization processes on ecosystem services in mega-urban agglomerations at the grid scale

The response mechanisms of ecosystem services to urbanization are crucial for urban planning and future sustainable management priorities. However, debates on the relationship between the two at the grid scale remain insufficient, and measurements of urbanization are often isolated rather than systematic. This study uses spatial association analysis and the geographically and temporally weighted regression model (GTWR) to analyze the response mechanisms of ecosystem services (habitat quality (HQ), food production (FP), carbon sequestration (CS), and soil conservation (SC)) to multi-dimensional urbanization (population, land, and economic urbanization) in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) at the grid scale. The results show that from 2000 to 2020, HQ and CS exhibited a declining trend, while FP and SC experienced overall growth. The most significant HQ losses were observed in Dongguan, Macao, and Shenzhen. Globally, UR and ES were predominantly negatively correlated in geographical space, with High-Low and Low-High agglomerations being the primary clustering types in localized spatial correlations. The spatial non-stationarity of the impacts of different dimensions of urbanization on ecosystem services is further validated. Urbanization in core and coastal areas generally has positive effects on ecosystem services, whereas the negative impacts on ecological conservation areas are significant. This research transcends administrative boundaries, offering new support for the development of localized ecological governance strategies and ecological service maintenance projects in the GBA. Additionally, it provides differentiated ecological governance strategies for river estuaries, mountainous hills, and central urban areas within coastal mega-urban agglomerations.