Planning urban landscape to maintain key ecosystem services in a rapidly urbanizing area: A scenario analysis in the Beijing-Tianjin-Hebei urban agglomeration, China

Planning urban landscape is essential for maintaining key ecosystem services (ESs) in rapidly urbanizing areas and has become one of the key questions in urban ecology and landscape ecology. In this study, we simulated the urban landscape dynamics in the Beijing-Tianjin-Hebei (BTH) urban agglomeration in China during the period of 2013-2040 under different ES conservation scenarios by combining ES conservation priority areas, the Land Use Scenario Dynamics-urban (LUSD-urban) model, and scenario analysis to explore approaches to planning urban landscapes with the goal of maintaining and conserving key ESs. We found that the key ESs could be effectively maintained with urban landscape planning in the BTH urban agglomeration. The loss of food production (FP) under the provisioning service conservation scenario will be 80.88% lower than that under the business-as-usual (BAU) scenario, and the loss of regulating services under the regulating service conservation scenario will be 1.42-10.34% lower than that under the BAU scenario. The loss of recreation service (RS) under the cultural service conservation scenario will be 41.52% lower than that under the BAU scenario. The integrative conservation scenario will be the best scenario to maintain ESs because the losses of FP, carbon storage (CS), water retention (WR), and air purification (AP) will be 29.31-78.49% lower than those under the BAU scenario. Protecting cropland and woodland will be an effective strategy in planning urban landscape to maintain key ESs. When cropland and woodland were protected, ES losses under the integrative conservation scenario will be 85.67-98.58% lower than those under the BAU scenario. Promoting the coordinated development of cities of different sizes will be another effective strategy in planning urban landscape. Under the best scenario of maintaining key ESs, i.e., the integrative conservation scenario, ESs in megacities and large cities can be protected, while ES losses will mainly occur in medium-sized cities. The ES losses in medium-sized cities will account for 60% of the total losses across the entire region. To ensure sustainable development in the BTH urban agglomeration, we suggest that effective policies and regulations be implemented to protect cropland and woodland areas and to promote the coordinated development of cities of different sizes to maintain key ESs.