The Alpine and Arctic tundra are warming 2-3 times faster than the Earth surface on average. How does vegetation react to this warming? What do plant traits tell us about changes in plant strategies? And what are consequences of these changes to other components of the Earth system?
130 researchers pulled together data measured during thousands of hours of field work at Alpine and Arctic sites to investigate vascular plant changes across the tundra biome. At almost all sites, plant height increased over the past 30 years, mainly by the immigration of taller species. However, changes toward more competitive, acquisitive plant traits were only pronounced in wet tundra sites. At warming, but dry sites, plant traits indicated more conservative strategies with moisture limiting plant growth.
Tundra plants were up to date strongly underrepresented in the international TRY plant trait data base. With the newly acquired data of this study, this gap is being filled and data are available to study biome-wide characteristics of tundra plants, urgently needed to better inform predictions of vegetation changes and related consequences for permafrost thaw and climate.
Gabriela Schaepman-Strub was part of the sTundra team that conceived the study. Her former PhD student, Maitane Iturrate-Garcia, spent two summers to collect the valuable data in the remote Siberian tundra. But the work is not done yet - this summer a new experiment was established in the Siberian tundra to further investigate and quantify the effects of drought and increased precipitation on plant strategies, and on the related feedbacks to permafrost and climate.
The UZH contribution to the publication has been funded by the University Research Priority Programme on Global Change and Biodiversity. The new precipitation experiment is further supported by a Swiss National Science Foundation project.
Bjorkman, A. et al. (2018): Plant functional trait change across a warming tundra biome. Nature, doi: doi.org/10.1038/s41586-018-0563-7
University of Zurich
Dr. Gabriela Schaepman Strub
Institute for Evolutionary Biology and Environmental Studies