Projecting species loss and turnover under climate change for 111 Chinese tree species

Climate-change-induced habitat loss will be the largest global threat to biodiversity. Therefore, quantifying regional species loss and turnover is important for alerting scientists and policymakers to potential future risks and supporting the development of proactive strategies to reduce the impact of climate change on biodiversity. Here, we projected species turnover and loss for 111 Chinese tree species under four climate change scenarios (representative concentration path ways 2.6 (RCP2.6), RCP4.5, RCP6.0, and RCP8.5). The results show that many Chinese trees will be seriously threatened and the extent of this threat depends firstly on the migration scenarios and secondly on the climate change scenarios. On average across RCP scenarios, about 57% or 23% of the trees would be vulnerable or threatened under no migration assumption or universal migration by 2070, respectively. Projection of species loss and turnover in grid cells indicates considerable variation across climate change scenarios (22-50% and 40-67%, respectively) and across geographical regions (25.4-58.1% and 40.6-78.8%, respectively). Species from arid regions and monsoon regions will undergo more species loss than alpine regions under climate change. This is the opposite for species turnover. Notably, extinction risks for Chinese trees species may be high; even under the most conservative situation (RCP2.6 and universal migration), 18% trees will still be vulnerable or threatened. We suggest that a further studying trees adaptation strategy to climate change is required to ensure the sustainable development of China's forests.