For measuring CH 4 emissions from rumi-
nants, the use of FT-SS chambers has seen wide
adoption since they can be easily calibrated and
offer a sensitive measure to emissions attributed
to dietary differences. In this environment the
differences in feed intake can also be easily moni-
tored and removed from the treatment effect. The
SF 6 tracer technique is commonly used for enteric
CH 4 emission measurements as well, but it is gen-
erally accepted to yield greater variability and
hence not as sensitive to treatment differences as
the FT-SS chamber technique. When the SF 6
tracer technique is used in a grazing system,
determining the feed intake (not easily meas-
ured) also confounds treatment differences.
Micrometeorological techniques for measuring
enteric CH 4 emissions from ruminants have more
of a role in developing emission factors for differ-
ent livestock since many of these techniques
require a large scale, e.g. farm or herd, and there-
fore replication needed for mitigation purposes is
In measuring CH 4 and/or NH 3 from
manure, often the outdoor environment is criti-
cal to the emission. In this situation, the micro-
meteorological techniques prove useful since
these techniques are not intrusive. Surface
chamber techniques suffer from spatial sam-
pling variability and typically do not provide a
continuous measure, whereas micrometeoro-
logical techniques are more conducive to con-
Barthelmie, R.J. and Pryor, S.C. (1998) Implications of ammonia emissions for fine aerosol formation and
visibility impairment: A case study from the Lower Fraser Valley, British Columbia. Atmospheric
Environment 32, 345-352.
Baum, K.A. and Ham, J.M. (2009) Adaptation of a speciation sampling cartridge for measuring ammonia
flux from cattle feedlots using relaxed eddy accumulation. Atmospheric Environment 43, 1753-1759.
Beauchemin, K.A., Coates, T., Farr, B. and McGinn, S.M. (2012) Can the sulphur hexafluoride tracer gas
technique be used to accurately measure enteric methane production from ruminally cannulated cattle?
Journal of Animal Science 90, 2727-2732.
Benchaar, C., Pomar, C. and Chiquette, J. (2001) Evaluation of dietary strategies to reduce methane pro-
duction in ruminants: A modelling approach. Canadian Journal of Animal Science 81, 563-574.
Bierman, S., Erickson, G.E., Klopfenstein, T.J., Stock, R.A. and Shain, D.H. (1999) Evaluation of nitrogen
and organic matter balance in the feedlot as affected by level and source of dietary fiber. Journal of
Animal Science 77, 1645-1653.
Bittman, S., van Viet, L.J.P., Kowalenko, G., McGinn, S.M., Hunt, D.E. and Boumaix, F. (2005) Surface-
banding liquid manure over aeration slots: a new low-disturbance method for reducing ammonia emis-
sions and improving yield of perennial grasses. Agronomy Journal 97, 1304-1313.
Bjorneberg, D.L., Leytem, A.B., Westermann, D.T., Griffiiths, P.R., Shao, L. and Pollard, M.J. (2009)
Measurements of atmospheric ammonia, methane, and nitrous oxide at a concentrated dairy produc-
tion facility in southern Idaho using open-path FTIR spectrometry. Transactions of the American
Society of Agricultural and Biological Engineers 52, 1749-1756.
Boadi, D.A., Wittenberg, K.M. and Kennedy, A.D. (2002) Validation of the sulfur hexafluoride (SF 6 ) tracer
gas technique for measurement of methane and carbon dioxide production by cattle. Canadian
Journal of Animal Science 82, 125-131.
Boadi, D.A., Benchaar, C., Chiquette, J. and Massé, D. (2004) Mitigation strategies to reduce enteric meth-
ane emissions from dairy cows: Update review. Canadian Journal of Animal Science 84, 319-335.
Cooprider, K.L., Mitloehner, F.M., Famula, T.R., Kebreab, E., Zhao, Y.J. and Van Eenennaam, A.L. (2011)
Feedlot efficiency implications on greenhouse gas emissions and sustainability. Journal of Animal
Science 89, 2643-2656.
Craggs, R., Park, J. and Heubeck, S. (2008) Methane emissions from anaerobic ponds on a piggery and
dairy farm in New Zealand. Australian Journal of Experimental Agriculture 48, 142-146.
Dengel, S., Levy, P.E., Grace, J., Jones, S.K. and Skiba, U.M. (2011) Methane emissions from sheep pasture,
measured with an open-path eddy covariance system. Global Change Biology 17, 3524-3533.
Denmead, O.T., Simpson, J.R. and Freney, J.R. (1974) Ammonia flux into the atmosphere from a grazed
pasture. Science 185, 609-610.