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In situ warming in the Antarctic: effects on growth and photosynthesis in Antarctic vascular plants
Author(s) -
Sáez Patricia L.,
Cavieres Lohengrin A.,
Galmés Jeroni,
GilPelegrín Eustaquio,
PegueroPina José Javier,
SanchoKnapik Domingo,
Vivas Mercedes,
Sanhueza Carolina,
Ramírez Constanza F.,
Rivera Betsy K.,
Corcuera Luis J.,
Bravo León A.
Publication year - 2018
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/nph.15124
Subject(s) - photosynthesis , vascular plant , biology , stomatal conductance , global warming , ecophysiology , carbon dioxide , carbon assimilation , botany , ecology , climate change , environmental science , species richness
Summary The Antarctic Peninsula has experienced a rapid warming in the last decades. Although recent climatic evidence supports a new tendency towards stabilization of temperatures, the impacts on the biosphere, and specifically on Antarctic plant species, remain unclear. We evaluated the in situ warming effects on photosynthesis, including the underlying diffusive, biochemical and anatomical determinants, and the relative growth of two Antarctic vascular species, Colobanthus quitensis and Deschampsia antarctica , using open top chambers ( OTCs ) and gas exchange measurements in the field. In C. quitensis , the photosynthetic response to warming relied on specific adjustments in the anatomical determinants of the leaf CO 2 transfer, which enhanced mesophyll conductance and photosynthetic assimilation, thereby promoting higher leaf carbon gain and plant growth. These changes were accompanied by alterations in the leaf chemical composition. By contrast, D. antarctica showed no response to warming, with a lack of significant differences between plants grown inside OTC s and plants grown in the open field. Overall, the present results are the first reporting a contrasting effect of in situ warming on photosynthesis and its underlying determinants, of the two unique Antarctic vascular plant species, which could have direct consequences on their ecological success under future climate conditions.