Adjustment of forest ecosystem root respiration as temperature warms
Burton, Andrew J.
Melillo, Jerry M.
Frey, Serita D.
MetadataShow full item record
Adjustment of ecosystem root respiration to warmer climatic conditions can alter the autotrophic portion of soil respiration and influence the amount of carbon available for biomass production. We examined 44 published values of annual forest root respiration and found an increase in ecosystem root respiration with increasing mean annual temperature (MAT), but the rate of this cross-ecosystem increase (Q10 = 1.6) is less than published values for short-term responses of root respiration to temperature within ecosystems (Q10 = 2 to 3). When specific root respiration rates and root biomass values were examined, there was a clear trend for decreasing root metabolic capacity (respiration rate at a standard temperature) with increasing MAT. There also were tradeoffs between root metabolic capacity and root system biomass, such that there were no instances of high growing season respiration rates and high root biomass occurring together. We also examined specific root respiration rates at three soil warming experiments at Harvard Forest, USA, and found decreases in metabolic capacity for roots from the heated plots. This decline could be due to either physiological acclimation or to the effects of co-occurring drier soils on the measurement date. Regardless of the cause, these findings clearly suggest that modeling efforts that allow root respiration to increase exponentially with temperature, with Q10 values of 2 or more, may over-predict root contributions to ecosystem CO2 efflux for future climates and underestimate the amount of C available for other uses, including NPP.
Author Posting. © The Author(s), 2008. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Journal of Integrative Plant Biology 50 (2008): 1467-1483, doi:10.1111/j.1744-7909.2008.00750.x.
Showing items related by title, author, creator and subject.
Chapin, F. Stuart; Woodwell, G. M.; Randerson, James T.; Rastetter, Edward B.; Lovett, G. M.; Baldocchi, Dennis D.; Clark, D. A.; Harmon, Mark E.; Schimel, David S.; Valentini, R.; Wirth, C.; Aber, J. D.; Cole, Jonathan J.; Goulden, Michael L.; Harden, J. W.; Heimann, M.; Howarth, Robert W.; Matson, P. A.; McGuire, A. David; Melillo, Jerry M.; Mooney, H. A.; Neff, Jason C.; Houghton, Richard A.; Pace, Michael L.; Ryan, M. G.; Running, Steven W.; Sala, Osvaldo E.; Schlesinger, William H.; Schulze, E.-D. (2006-01-06)Recent patterns and projections of climatic change have focused increased scientific and public attention on patterns of carbon (C) cycling and its controls, particularly the factors that determine whether an ecosystem is ...
Variability in the carbon isotopic composition of foliage carbon pools (soluble carbohydrates, waxes) and respiration fluxes in southeastern U.S. pine forests Mortazavi, Behzad; Conte, Maureen H.; Chanton, Jeffrey P.; Weber, John C.; Martin, Timothy A.; Cropper, Wendell P. (American Geophysical Union, 2012-04-19)We measured the δ13C of assimilated carbon (foliage organic matter (δCOM), soluble carbohydrates (δCSC), and waxes (δCW)) and respiratory carbon (foliage (δCFR), soil (δCSR) and ecosystem 13CO2 (δCER)) for two years at ...
Seasonal patterns of carbon dioxide and water fluxes in three representative tundra ecosystems in northern Alaska Euskirchen, E. S.; Bret-Harte, M. Syndonia; Scott, G. J.; Edgar, C.; Shaver, Gaius R. (Ecological Society of America, 2012-01-19)Understanding the carbon dioxide and water fluxes in the Arctic is essential for accurate assessment and prediction of the responses of these ecosystems to climate change. In the Arctic, there have been relatively few ...