Potential wilderness loss could undermine the post-2020 global biodiversity framework.

Wilderness loss is one of the main threats to biodiversity conservation and sustainable development. The post-2020 Global Biodiversity Framework of the Convention on Biological Diversity proposes "retaining wilderness areas" in the first target of the 21 action-oriented targets for 2030. However, we know little about the spatiotemporal pattern of potential wilderness loss in the future. We conducted the global analysis of projected loss of wilderness area (PLWA) due to land use and land cover change (LUCC) by 2100. This analysis has a spatial resolution of 1 km*1 km and emphasizes the impact of cropland and urban expansion considering multiple SSP-RCP scenarios. We found that a total of 4.6 million km2 of wilderness is susceptible to cropland and urban expansion (1.3 times larger than India) by 2100. Alarmingly, >51 % of PLWA is concentrated in just ten countries, and >23 % of terrestrial protected areas are projected to experience some PLWA. We call for urgent conservation actions to prevent further wilderness loss which is essential to fulfilling the post-2020 global biodiversity conservation goals. • A total of 4.6 million km2 of wilderness might be threatened by cropland and urban expansion at global scale. • Wilderness areas adjacent to areas with high human impact require urgent conservation actions. • More than 23 % of terrestrial protected areas are projected to experience wilderness loss. • A "Warning List of Protected Areas" is created calling for wilderness conservation. [ABSTRACT FROM AUTHOR]