Carbon Dioxide and Methane Fluxes From Tree Stems, Coarse Woody Debris, and Soils in an Upland Temperate Forest
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Forest soils and canopies are major components of ecosystem CO2 and CH4 fluxes. In contrast, less is known about coarse woody debris and living tree stems, both of which function as active surfaces for CO2 and CH4 fluxes. We measured CO2 and CH4 fluxes from soils, coarse woody debris, and tree stems over the growing season in an upland temperate forest. Soils were CO2 sources (4.58 ± 2.46 µmol m−2 s−1, mean ± 1 SD) and net sinks of CH4 (−2.17 ± 1.60 nmol m−2 s−1). Coarse woody debris was a CO2 source (4.23 ± 3.42 µmol m−2 s−1) and net CH4 sink, but with large uncertainty (−0.27 ± 1.04 nmol m−2 s−1) and with substantial differences depending on wood decay status. Stems were CO2 sources (1.93 ± 1.63 µmol m−2 s−1), but also net CH4 sources (up to 0.98 nmol m−2 s−1), with a mean of 0.11 ± 0.21 nmol m−2 s−1 and significant differences depending on tree species. Stems of N. sylvatica, F. grandifolia, and L. tulipifera consistently emitted CH4, whereas stems of A. rubrum, B. lenta, and Q. spp. were intermittent sources. Coarse woody debris and stems accounted for 35% of total measured CO2 fluxes, whereas CH4 emissions from living stems offset net soil and CWD CH4 uptake by 3.5%. Our results demonstrate the importance of CH4 emissions from living stems in upland forests and the need to consider multiple forest components to understand and interpret ecosystem CO2 and CH4 dynamics.
Keywordscarbon cycle forested watershed biogeochemistry methane carbon dioxide
This study was funded by the US Department of Agriculture (USDA-AFRI Grant 2013-02758) and State of Delaware’s Federal Research and Development Matching Grant Program. RV and KM acknowledge support from the Delaware Water Research Center. We thank Zulia Sanchez, Jillian Swank, the UD Soil Testing Facility, and the Delaware Environmental Observation System for field and laboratory support.
- Amthor JS. 1984. The role of maintenance respiration in plant growth. Plant Cell Environ 7:561–9.Google Scholar
- Delaware Environmental Observing System (DEOS). 2014. Newark, DE: University of Delaware.Google Scholar
- Edwards NT, Hanson PJ. 1996. Stem respiration in a closed-canopy upland oak forest. Tree Physiol 16:433–9. http://treephys.oxfordjournals.org/content/16/4/433.abstract
- Forster P, Ramaswamy V, Artaxo P, Berntsen T, Betts R, Fahey D, Haywood J, Lean J, Lowe D, Myhre G, Nganga J, Prinn R, Raga G, Schulz M, Van Dorland R. 2007. Changes in atmospheric constituents and in radiative forcing. In: Nakajima T, Ramanathan V, editors. Climate change 2007: the physical science basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, pp 129–234. http://en.scientificcommons.org/23467316
- Lloyd J, Taylor JA. 1994. On the temperature dependence of soil respiration. Funct Ecol 8:315–23. http://www.jstor.org/stable/2389824?origin=crossref. Last accessed 30/10/2014
- Pachauri RK, Allen MR, Barros VR, Broome J, Cramer W, Christ R, Church J a., Clarke L, Dahe Q, Dasgupta P, Dubash NK, Edenhofer O, Elgizouli I, Field CB, Forster P, Friedlingstein P, Fuglestvedt J, Gomez-Echeverri L, Hallegatte S, Hegerl G, Howden M, Jiang K, Cisneros BJ, Kattsov V, Lee H, Mach KJ, Marotzke J, Mastrandrea MD, Meyer L, Minx J, Mulugetta Y, O’Brien K, Oppenheimer M, Pereira JJ, Pichs-Madruga R, Plattner G-K, Pörtner H-O, Power SB, Preston B, Ravindranath NH, Reisinger A, Riahi K, Rusticucci M, Scholes R, Seyboth K, Sokona Y, Stavins R, Stocker TF, Tschakert P, Vuuren D Van, Ypersele J-P Van. 2014. IPCC climate change 2014: synthesis report.Google Scholar
- Pan Y, Birdsey RA, Fang J, Houghton R, Kauppi PE, Kurz WA, Phillips OL, Shvidenko A, Lewis SL, Canadell JG, Ciais P, Jackson RB, Pacala SW, McGuire AD, Piao S, Rautiainen A, Sitch S, Hayes D. 2011. A large and persistent carbon sink in the world’s forests. Science 333:988–93. doi: 10.1126/science.1201609.CrossRefPubMedGoogle Scholar
- Pumpanen J, Kolari P, Ilvesniemi H, Minkkinen K, Vesala T, Niinistö S, Lohila A, Larmola T, Morero M, Pihlatie M, Janssens I, Yuste JC, Grünzweig JM, Reth S, Subke JA, Savage K, Kutsch W, Østreng G, Ziegler W, Anthoni P, Lindroth A, Hari P. 2004. Comparison of different chamber techniques for measuring soil CO2 efflux. Agric For Meteorol 123:159–76.CrossRefGoogle Scholar
- R Core Team. 2015. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. http://R-project.org.
- Rodhe H. 1990. A comparison of the contribution of various gases to the greenhouse effect. Science 248:1217–9. http://www.ncbi.nlm.nih.gov/pubmed/17809907. Last accessed 21 Dec 2014
- Smith KA, Dobbie KE, Ball BC, Bakken LR, Sitaula BK, Hansen S, Brumme R, Borken W, Christensen S, Priemé A, Fowler D, Macdonald JA, Skiba U, Klemedtsson L, Kasimir-Klemedtsson A, Degórska A, Orlanski P. 2000. Oxidation of atmospheric methane in Northern European soils, comparison with other ecosystems, and uncertainties in the global terrestrial sink. Global Change Biol 6:791–803.CrossRefGoogle Scholar
- Vito M, Muggeo R. 2008. Segmented: an R package to fit regression models with broken-line relationships. R News 8(1):20–5.Google Scholar