A team led by Prof. WANG Wei from the Institute of Botany of the Chinese Academy of Sciences (IBCAS) has predicted quantitativelythe potential dynamic changes of the entire Arctic flora from now until 2100 under four greenhouse gas emission scenarios. The study was published in National Science Review.

The Arctic tundra, to the north of the natural tree line, harbors a unique and fragile flora, yet is experiencing climate change at unparalleled rates and magnitudes. For conservation and landscape management there is an urgent need to predict the responses of the Arctic flora to future warming. However, little is known about how the Arctic flora will develop, spatially and temporally, under such change.

In this study, the authors incorporated predictions of 1,187 species, covering about 58% Arctic vascular plant species, to predict potential floristic changes throughout the Arctic from now until 2100 under four greenhouse gas emission scenarios. They first generated 20,179 potential distribution maps capturing the changes of the mean species area of habitat and mean species richness for the entire Arctic, as well as within each of five component sectors, and calculated the direction and magnitude of the mean distributional centroid in each floristic sector.

Their study shows widespread, but heterogeneous, changes in the Arctic flora throughout the 21st century with, surprisingly, trends reversing in some circumstances. They discover that the Beringia sector and Arctic coastal regions will experience the most rapid biodiversity loss, warranting urgent attention. Around the 2070s, possibly earlier, the mean species area of habitat and mean species richness of the Arctic flora may decline, with northward migration decelerating in Canada and potentially halting in Eastern Siberia and North Atlantic sectors, implying time to avoid irreversible loss of the Arctic flora and its ecosystem functions is fast running out. The potential responses of the Arctic flora under different emission scenarios are temporally displaced, highlighting the considerable benefits of controlling greenhouse gas emissions to limit global warming to below 2 °C.

Unlike previous simulation studies focusing on a few species, individual taxa, and/or local area, this study predicted and quantified the potential long-term changes of the whole flora under four greenhouse gas emission scenario based on an ensemble modelling approach. Moreover, the authors highlighted that both global and regional actions are required to drastically reduce greenhouse gas emissions and mitigate the detrimental effects on the Arctic flora.

Potential changes of the Arctic flora and its sectors from now to 2100 under four greenhouse gas emission scenarios. (Image by IBCAS)