Leaf- and cell-level carbon cycling responses to a nitrogen and phosphorus gradient in two Arctic tundra species

TitleLeaf- and cell-level carbon cycling responses to a nitrogen and phosphorus gradient in two Arctic tundra species
Publication TypeJournal Article
Year of Publication2012
AuthorsHeskel, Mary A., Anderson O. R., Atkin O. K., Turnbull M. H., and Griffin Kevin L.
JournalAmerican Journal of Botany
Volume99
Pagination1702 - 1714
Date Published10/2012
ISSN1537-2197
KeywordsAnalysis of Variance, Arctic Regions, Betula, biomass, carbon cycle, carbon dioxide, Cell Respiration Chloroplasts, Cyperaceae, cytology, Fertilization, Light, Mesophyll Cells, METABOLISM, Mitochondria, nitrogen, Oxygen Consumption, phosphorus, photosynthesis, Plant Leaves, radiation effects, Seasons, Temperature
Abstract

Consequences of global climate change are detectable in the historically nitrogen- and phosphorus-limited Arctic tundra landscape and have implications for the terrestrial carbon cycle. Warmer temperatures and elevated soil nutrient availability associated with increased microbial activity may influence rates of photosynthesis and respiration. • METHODS: This study examined leaf-level gas exchange, cellular ultrastructure, and related leaf traits in two dominant tundra species, Betula nana, a woody shrub, and Eriophorum vaginatum, a tussock sedge, under a 3-yr-old treatment gradient of nitrogen (N) and phosphorus (P) fertilization in the North Slope of Alaska. • KEY RESULTS: Respiration increased with N and P addition-the highest rates corresponding to the highest concentrations of leaf N in both species. The inhibition of respiration by light ("Kok effect") significantly reduced respiration rates in both species (P

DOI10.3732/ajb.1200251