Direct and indirect losses of natural habitat caused by future urban expansion in the transnational area of Changbai Mountain

Assessing the potential natural habitat losses caused by future urban expansion is important for understanding the cascading effect of urbanization on the environment and improving urban landscape sustainability. However, few studies have assessed the indirect loss of natural habitat resulting from urban expansion. Taking the transnational area of Changbai Mountain (TACM) as study area, we evaluated the potential loss of natural habitat caused by urban expansion during 2015–2050. We first quantified the spatial pattern of natural habitat. Second, urban expansion was simulated by using the Shared Socioeconomic Pathways (SSPs) and the zoned Land Use Scenario Dynamics-urban (LUSD-urban) model. Finally, direct and indirect losses of natural habitat were calculated and compared. The results indicated that 56.97–153.90 km² of natural habitat will be lost directly caused by urban expansion during 2015–2050, while 77.76–318.78 km² will be lost resulting from cropland displacement. The indirect loss will be 1.36–2.12 times higher than the direct loss. Furthermore, the indirect loss of natural habitat will be 2.21–3.15 times greater than the direct loss on the Democratic People’s Republic of Korea’s (DPRK) side. To promote regional sustainable development, effective policies and measures should be enacted to balance urban expansion, cropland displacement, and natural habitat conservation.