Urban ecosystem services, ecological security patterns and ecological resilience in coastal cities: The impact of land reclamation in Macao SAR.

Land reclamation from the sea is a common practice to create territorial space and accommodate urbanisation in coastal cities. However, previous studies did not adequately examine the changes in ecosystem service values, the spatial transformation of the ecological network and the ecological resilience at an urban scale in the context of land reclamation. This study uses Macao SAR, a fully urbanised city with two-thirds of its land reclaimed from the sea, as a case study. We quantify urban ecosystem services (UES) values and model the spatial transformation of the ecological security patterns (ESPs) throughout the city's land reclamation history from 2000 to 2020. Subsequently, we evaluate the resilience of the ESPs' components and their relationships with urbanisation by using spatial element elasticity indices and regression analysis. Results show that urban land expanded by 27% through land reclamation, increasing the value of UES by 13%. The growth rates of different categories of UES vary significantly. ESPs extended over the newly reclaimed and urbanised lands, but the resilience levels of ecological sources, corridors and nodes decreased. There is a strong positive correlation between UES values and urbanisation, and a strong negative correlation between ecological resilience and urbanisation. This study recommends five specific environmental spatial planning and management strategies to address the expansion and integration of ESPs, aiming not only to provide ecological services but also to enhance ecological resilience in coastal cities.