Canopy nitrogen, carbon assimilation, and albedo in temperate and boreal forests: Functional relations and potential climate feedbacks

S. V. Ollinger, A. D. Richardson, M. E. Martin, D. Y. Hollinger, S. E. Frolking, P. B. Reich, L. C. Plourde, G. G. Katul, J. W. Munger, R. Oren, M. L. Smith, K. T. Paw U, P. V. Bolsta, B. D. Cook, M. C. Day, T. A. Martin, R. K. Monson, H. P. Schmid

Research output: Contribution to journalArticlepeer-review

304 Scopus citations

Abstract

The availability of nitrogen represents a key constraint on carbon cycling in terrestrial ecosystems, and it is largely in this capacity that the role of N in the Earth's climate system has been considered. Despite this, few studies have included continuous variation in plant N status as a driver of broad-scale carbon cycle analyses. This is partly because of uncertainties in how leaf-level physiological relationships scale to whole ecosystems and because methods for regional to continental detection of plant N concentrations have yet to be developed. Here, we show that ecosystem CO2 uptake capacity in temperate and boreal forests scales directly with whole-canopy N concentrations, mirroring a leaf-level trend that has been observed for woody plants worldwide. We further show that both CO2 uptake capacity and canopy N concentration are strongly and positively correlated with shortwave surface albedo. These results suggest that N plays an additional, and overlooked, role in the climate system via its influence on vegetation reflectivity and shortwave surface energy exchange. We also demonstrate that much of the spatial variation in canopy N can be detected by using broad-band satellite sensors, offering a means through which these findings can be applied toward improved application of coupled carbon cycle-climate models.

Original languageEnglish (US)
Pages (from-to)19336-19341
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume105
Issue number49
DOIs
StatePublished - Dec 9 2008
Externally publishedYes

Keywords

  • Climate change
  • Ecosystem-climate feedback
  • Foliar nitrogen
  • Nitrogen cycle
  • Remote sensing

ASJC Scopus subject areas

  • General

Fingerprint

Dive into the research topics of 'Canopy nitrogen, carbon assimilation, and albedo in temperate and boreal forests: Functional relations and potential climate feedbacks'. Together they form a unique fingerprint.

Cite this