Stable isotopic signatures (δ13C, δD) of methane from European landfill sites

The stable isotopic signatures (δ13C, δD) of CH4 from four German and Dutch landfill sites have been characterized using different techniques for isotope analysis (tunable diode laser absorption spectroscopy and isotope ratio mass spectrometry). Samples taken directly from the gas collection systems show fairly uniform, biogenic δ13C-δD isotopic signatures [δ13C = (−59.0±2.2)‰ VPDB (n = 104); δD = (−304±10)‰ VSMOW (n = 46)]. In contrast, emission samples taken with static chambers on soil-covered landfill areas exhibit a considerable δ13C-δD variability, mainly due to the influence of aerobic bacterial CH4 oxidation, which occurs when the biogas CH4 encounters atmospheric oxygen available in the uppermost region of the cover soil. Soil gas samples from the landfill covers clearly show the progressive isotopic enrichment within the aerobic regions of the soil. Isotope fractionation factors due to CH4 oxidation were determined to be α(δ13C) = 1.008±0.004 and α(δD) = 1.039±0.026. On average, about 80% (70–97%) of CH4 is oxidized during the transport through cover soils, while no significant CH4 oxidation was found in uncovered areas consisting of freshly dumped waste. Area-integrated δ13C values of total emissions were derived from upwind-downwind measurements around the landfill and show very little temporal and site-to-site variation (δ13C = (−55.4±1.4)‰ VPDB (n = 13; four different landfills)). CH4 budgets were established for two landfill sites, indicating that projected CH4 surface emissions from uncovered and covered areas are significantly lower compared to total CH4 production (for a landfill without gas collection) or compared to the difference between CH4 production and recovery (for a landfill with a gas collection system). For these two landfill sites the overall fraction of CH4 oxidation is estimated to be 46 and 39% (53%) of total CH4 production (minus recovery). Furthermore, the δ13C balance (comparing the δ13C values of the different emission pathways with the area-integrated δ13C results) implies that direct CH4 emissions via cracks or leakages constituted the major transport pathway (∼70%) into the atmosphere in both landfills.

[1]  P. Czepiel,et al.  Use of stable isotopes to determine methane oxidation in landfill cover soils , 1998 .

[2]  P. Crutzen,et al.  Isotope analysis based source identification for atmospheric CH4 and CO sampled across Russia using the Trans-Siberian railroad , 1998 .

[3]  P. Bergamaschi.  Seasonal variations of stable hydrogen and carbon isotope ratios in methane from a Chinese rice paddy , 1997 .

[4]  M. Manning,et al.  The 1991–1992 atmospheric methane anomaly: Southern hemisphere 13C decrease and growth rate fluctuations , 1997 .

[5]  Paul J. Crutzen,et al.  An inverse modeling approach to investigate the global atmospheric methane cycle , 1997 .

[6]  R. Cicerone,et al.  Modeling atmospheric δ13CH4 and the causes of recent changes in atmospheric CH4 amounts , 1996 .

[7]  P. Crutzen,et al.  Implications of the large carbon kinetic isotope effect in the reaction CH4 + Cl for the 13C/12C ratio of stratospheric CH4 , 1996 .

[8]  P. Crutzen,et al.  A Large 13CO deficit in the lower Antarctic stratosphere due to “ozone hole” chemistry: Part II, Modeling , 1996 .

[9]  Patrick M. Crill,et al.  Quantifying the effect of oxidation on landfill methane emissions , 1996 .

[10]  M. Carlowicz.  Galileo brings new weight to studies of Jupiter System , 1996 .

[11]  G. W. Harris,et al.  Measurements of stable isotope ratios (13CH4/12CH4; 12CH3D/12CH4) in landfill methane using a tunable diode laser absorption spectrometer. [Erratum to document cited in CA124:65076] , 1995 .

[12]  T. Coplen,et al.  Reporting of stable hydrogen, carbon, and oxygen isotopic abundances , 1995 .

[13]  G W Harris,et al.  High-precision direct measurements of (13)CH(4)/(12)CH(4) and (12)CH(3)D/(12)CH(4) ratios in atmospheric methane sources by means of a long-path tunable diode laser absorption spectrometer. , 1994, Applied optics.

[14]  J. Chanton,et al.  The influence of methane oxidation on the stable isotopic composition of methane emitted from Florida swamp forests , 1994 .

[15]  David C. Lowe,et al.  Concentration and 13C records of atmospheric methane in New Zealand and Antarctica: Evidence for changes in methane sources , 1994 .

[16]  G. Brailsford,et al.  Seasonal variations in methane flux andδl3CH4 values for rice paddies in Japan and their implications , 1994 .

[17]  P. Crill,et al.  13C12C Fractionation of methane during oxidation in a temperate forested soil , 1994 .

[18]  Tyler B. Coplen,et al.  Reporting of stable hydrogen, carbon, and oxygen isotopic abundances (Technical Report) , 1994 .

[19]  Peter Bergamaschi,et al.  High Precision Direct Measurements of 13CH4/12CH4 and 12CH3D/12CH4 Ratios in by means of a Long Path Diode Laser Absorption Spectrometer , 1994 .

[20]  J. Chanton,et al.  Rhizospheric methane oxidation determined via the methyl fluoride inhibition technique , 1993 .

[21]  David von Hippel,et al.  National greenhouse gas accounts: Current anthropogenic sources and sinks , 1993 .

[22]  M. Wahlen.  The Global Methane Cycle , 1993 .

[23]  P. Bergamaschi,et al.  Stable isotopic signature of methane from major sources in Germany , 1993 .

[24]  Martina Schmidt,et al.  The regional budget of atmospheric methane of a highly populated area , 1993 .

[25]  R. A. Burke,et al.  Seasonal variations of stable hydrogen and carbon isotope ratios of methane in subtropical freshwater sediments , 1992 .

[26]  R. Oremland,et al.  Importance of methane-oxidizing bacteria in the methane budget as revealed by the use of a specific inhibitor , 1992, Nature.

[27]  G. King.  Ecological Aspects of Methane Oxidation, a Key Determinant of Global Methane Dynamics , 1992 .

[28]  Inez Y. Fung,et al.  Carbon isotopic composition of atmospheric CH4: Fossil and biomass burning source strengths , 1991 .

[29]  G. King.  Dynamics and controls of methane oxidation in a Danish wetland sediment , 1990 .

[30]  K. A. Sandbeck,et al.  Rapid Methane Oxidation in a Landfill Cover Soil , 1990, Applied and environmental microbiology.

[31]  G. King,et al.  Distribution and Rate of Methane Oxidation in Sediments of the Florida Everglades , 1990, Applied and environmental microbiology.

[32]  Helmut Schütz,et al.  Processes involved in formation and emission of methane in rice paddies , 1989 .

[33]  R. A. Burke,et al.  Methane flux and stable hydrogen and carbon isotope composition of sedimentary methane from the Florida Everglades , 1988 .

[34]  C. Martens,et al.  Seasonal variations of D/H and 13C/12C ratios of microbial methane in surface sediments , 1988, Nature.

[35]  C. M. Stevens,et al.  Stable carbon isotopic composition of methane from some natural and anthropogenic sources , 1988 .

[36]  G. Hut.  Consultants' group meeting on stable isotope reference samples for geochemical and hydrological investigations , 1987 .

[37]  P. Crutzen,et al.  The Production of Methane From Solid Wastes , 1987 .

[38]  S. Tyler.  Stable carbon isotope ratios in atmospheric methane and some of its sources , 1986 .

[39]  C. Martens,et al.  Seasonal variations in the stable carbon isotopic signature of biogenic methane in a coastal sediment. , 1986, Science.

[40]  Michael J. Whiticar,et al.  Biogenic methane formation in marine and freshwater environments: CO2 reduction vs. acetate fermentation—Isotope evidence , 1986 .

[41]  J. Barker,et al.  Carbon isotope fractionation during microbial methane oxidation , 1981, Nature.

[42]  Martin Schoell,et al.  Fractionation of carbon and hydrogen isotopes by methane-oxidizing bacteria , 1981 .

[43]  G. L. Hutchinson,et al.  Improved Soil Cover Method for Field Measurement of Nitrous Oxide Fluxes , 1981 .

[44]  B. Kromer,et al.  Field determination of air-sea gas exchange by continuous measurement of radon-222 , 1978 .

[45]  B. Kimball,et al.  Air Turbulence Effects upon Soil Gas Exchange1 , 1971 .

[46]  V. Oyama,et al.  Automatic apparatus for sampling and preparing gases for mass spectral analysis in studies of carbon isotope fractionation during methane metabolism. , 1968, Analytical chemistry.