RT Journal Article
SR Electronic
T1 Climatic warming strengthens a positive feedback between alpine shrubs and fire
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 043919
DO 10.1101/043919
A1 James S. Camac
A1 Richard J. Williams
A1 Carl-Henrik Wahren
A1 Ary A. Hoffmann
A1 Peter A. Vesk
YR 2016
UL http://biorxiv.org/content/early/2016/03/16/043919.abstract
AB Climate change is expected to increase fire activity and woody plant encroachment in arctic and alpine landscapes. However, it is unknown whether increases in woody species and fire will interact to exacerbate changes in structure, function and composition of these ecosystems. Here we use field surveys and experimental manipulations to examine warming and fire effects on recruitment, growth and survival of seedlings of evergreen obligate seeding alpine shrubs. We find that fire substantially increased shrub seedling establishment (up to 32–fold) and that warming doubled tall shrub seedling growth rates and could increase survival. Warming had limited or no effect on shrub recruitment, post-fire gap-infilling by grass, or competitive effects of grass on shrub seedling growth and survival. These findings indicate that rising temperatures coupled with more frequent or severe fires will likely exacerbate increases in tall evergreen shrubs by increasing recruitment, doubling growth rates, and potentially increasing shrub survival.