Global assessment of experimental climate warming on tundra vegetation: heterogeneity over space and time

TitleGlobal assessment of experimental climate warming on tundra vegetation: heterogeneity over space and time
Publication TypeJournal Article
Year of Publication2012
AuthorsElmendorf S.C, Henry G.HR, Hollister R.D, Bjork R.G, Bjorkman A.D, Callaghan T.V, Collier L.S, Cooper E.J, Cornelissen J.HC, Day T.A, Fosaa A.M, Gould W.A, Gretarsdottir J., Harte J., Hermanutz L., Hik D.S, Hofgaard A., Jarrad F., Jonsdottir I.S, Keuper F., Klanderud K., Klein J.A, Koh S., Kudo G., Lang S.I, Loewen V., May J.L, Mercado J., Michelsen A., Molau U., Myers-Smith I.H, Oberbauer S.F, Pieper S., Post E., Rixen C., Robinson C.H, Schmidt N.M, Shaver GR, Stenstrom A., Tolvanen A., Totland O., Troxler T., Wahren C.H, Webber P.J, Welker J.M, Wookey P.A
JournalEcology LettersEcology LettersEcology Letters
Volume15
Pagination164-175
Date PublishedFeb
ISBN Number1461-023X
Accession NumberISI:000298848200011
Keywordsalpine, arctic, Arctic tundra, climate warming, ecosystems, functional types, growth, long-term experiment, meta-analysis, metaanalysis, northern sweden, plant community responses, plants, shrub expansion, simulated environmental-change, tibetan plateau
Abstract

Understanding the sensitivity of tundra vegetation to climate warming is critical to forecasting future biodiversity and vegetation feedbacks to climate. In situ warming experiments accelerate climate change on a small scale to forecast responses of local plant communities. Limitations of this approach include the apparent site-specificity of results and uncertainty about the power of short-term studies to anticipate longer term change. We address these issues with a synthesis of 61 experimental warming studies, of up to 20 years duration, in tundra sites worldwide. The response of plant groups to warming often differed with ambient summer temperature, soil moisture and experimental duration. Shrubs increased with warming only where ambient temperature was high, whereas graminoids increased primarily in the coldest study sites. Linear increases in effect size over time were frequently observed. There was little indication of saturating or accelerating effects, as would be predicted if negative or positive vegetation feedbacks were common. These results indicate that tundra vegetation exhibits strong regional variation in response to warming, and that in vulnerable regions, cumulative effects of long-term warming on tundra vegetation and associated ecosystem consequences have the potential to be much greater than we have observed to date.

Short TitleEcol LettEcol Lett
Alternate JournalEcol Lett