Landfill methane oxidation response to vegetation, fertilization, and liming

Journal Article · Tue Feb 01 04:00:00 EST 2000 · Journal of Environmental Quality

DOI:https://doi.org/10.2134/jeq2000.00472425002900010041x· OSTI ID:20075836

Hilger, H A; Wollum, A G; Barlaz, M A

Landfills are the fourth largest global source and the largest US source (USDOE, 1997) of anthropogenic CH{sub 4} emissions. Since gram-for-gram, CH{sub 4} has 21 times the 100-yr global-warming potential of CO{sub 2} (USEPA, 1990). CH{sub 4} release into the atmosphere has important implications for global climate change. This study was conducted to evaluate the effects of vegetation, N fertilizers, and lime addition on landfill CH{sub 4} oxidation. Columns filled with compacted sandy loam and sparged with synthetic landfill gas were used to simulate a landfill cover. Grass-topped and bare-soil columns reduced inlet CH{sub 4} by 47 and 37%, respectively, at peak uptake; but the rate for both treatments was about 18% at steady state. Nitrate and NH{sub 4} amendments induced a more rapid onset of CH{sub 4} oxidation relative to KCl controls. However, at steady state, NH{sub 4} inhibited CH{sub 4} oxidation in bare columns but not in grassed columns. Nitrate addition produced no inhibitory effects. Lime addition to the soil consistently enhanced CH{sub 4} oxidation. In all treatments, CH{sub 4} consumption increased to a peak value, then declined to a lower steady-state value; and all gassed columns developed a pH gradient. Neither nutrient depletion nor protozoan grazing could explain the decline from peak oxidation levels. Ammonium applied to grassed cover soil can cause transient reductions in CH{sub 4} uptake, but there is no evidence that the inhibition persists. The ability of vegetation to mitigate NH{sub 4} inhibition indicates that results from bare-soil tests may not always generalize to vegetated landfill caps.

• Research Organization: Univ. of North Carolina, Charlotte, NC (US)
• OSTI ID: 20075836
• Journal Information: Journal of Environmental Quality, Journal Name: Journal of Environmental Quality Journal Issue: 1 Vol. 29; ISSN JEVQAA; ISSN 0047-2425
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CLIMATIC CHANGE
COVERINGS
ENVIRONMENTAL IMPACTS
LIMING
METHANE
NITRATES
PLANTS
POLLUTION SOURCES
SANITARY LANDFILLS