Methane emissions from terrestrial plants under aerobic conditions

  title={Methane emissions from terrestrial plants under aerobic conditions},
  author={Frank Keppler and John T. G. Hamilton and Marc Bra{\ss} and Thomas R{\"o}ckmann},
Methane is an important greenhouse gas and its atmospheric concentration has almost tripled since pre-industrial times. It plays a central role in atmospheric oxidation chemistry and affects stratospheric ozone and water vapour levels. Most of the methane from natural sources in Earth's atmosphere is thought to originate from biological processes in anoxic environments. Here we demonstrate using stable carbon isotopes that methane is readily formed in situ in terrestrial plants under oxic… 
Methane emission from terrestrial herbaceous plant
Methane(CH4) is an important greenhouse gas and its atmospheric concentration has almost tripled since pre-industrial times. It plays a central role in atmospheric oxidation chemistry and affects
Three decades of global methane sources and sinks
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Biogeosciences Non-microbial methane formation in oxic soils
Methane plays an important role as a radiatively and chemically active gas in our atmosphere. Until recently, sources of atmospheric methane in the biosphere have been attributed to strictly
Methane formation in aerobic environments
Methane (CH_4), the second principal anthropogenic greenhouse gas after CO_2, is the most abundant reduced organic compound in the atmosphere and plays a central role in atmospheric chemistry.
Stable isotopes provide revised global limits of aerobic methane emissions from plants
Recently Keppler et al. (2006) discovered a surprising new source of methane – terrestrial plants under aerobic conditions, with an estimated global production of 62–236 Tg yr −1 by an unknown
Global change: A green source of surprise
  • D. Lowe
  • Environmental Science
  • 2006
living plants, as well as plant litter, emit methane to the atmosphere under oxic conditions, which could account for 10–30% of the annual methane source strength and has been overlooked in previous studies.
Aerobic methane production from organic matter
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Abstract. We report that the most abundant C1 units of terrestrial plants, the methoxyl groups of pectin and lignin, have a unique carbon isotope signature exceptionally depleted in 13C.
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Measurements of 13C in atmospheric methane made at Baring Head, New Zealand (41°S), over the 4-year period, 1989–1993, display a persistent but highly variable seasonal cycle. Values for δ13C peak in
Unexpected Changes to the Global Methane Budget over the Past 2000 Years
It is suggested that both human activities and natural climate change influenced preindustrial biomass burning emissions and that these emissions have been previously understated in late preindustrial Holocene methane budget research.
The trend in atmospheric methane δ13C and implications for isotopic constraints on the global methane budget
A recent paper by Tans [1997] has drawn attention to the isotopic disequilibrium that inevitably prevails when atmospheric methane is not in steady state with its sources, noting in particular the
Atmospheric methane levels off: Temporary pause or a new steady‐state?
The globally‐averaged atmospheric methane abundance determined from an extensive network of surface air sampling sites was constant at ∼1751 ppb from 1999 through 2002. Assuming that the methane
Assessing Methane Emissions from Global Space-Borne Observations
This work retrieved the global methane distribution by using spaceborne near-infrared absorption spectroscopy and observed unexpectedly high methane concentrations over tropical rainforests, revealing that emission inventories considerably underestimated methane sources in these regions during the time period of investigation.
Chloride Methylation by Plant Pectin: An Efficient Environmentally Significant Process
Evidence is presented here that CH3Cl is produced in many terrestrial environments by a common mechanism, and this ubiquitous process acting in terrestrial ecosystems and during biomass burning could contribute the bulk of atmosphericCH3Cl.