Philosophical Transactions of the Royal Society B: Biological Sciences
Restricted access

Greenhouse gas mitigation in agriculture

Published:https://doi.org/10.1098/rstb.2007.2184

    Agricultural lands occupy 37% of the earth's land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions. Agricultural soils may also act as a sink or source for CO2, but the net flux is small. Many agricultural practices can potentially mitigate greenhouse gas (GHG) emissions, the most prominent of which are improved cropland and grazing land management and restoration of degraded lands and cultivated organic soils. Lower, but still significant mitigation potential is provided by water and rice management, set-aside, land use change and agroforestry, livestock management and manure management. The global technical mitigation potential from agriculture (excluding fossil fuel offsets from biomass) by 2030, considering all gases, is estimated to be approximately 5500–6000 Mt CO2-eq. yr−1, with economic potentials of approximately 1500–1600, 2500–2700 and 4000–4300 Mt CO2-eq. yr−1 at carbon prices of up to 20, up to 50 and up to 100 US$ t CO2-eq.−1, respectively. In addition, GHG emissions could be reduced by substitution of fossil fuels for energy production by agricultural feedstocks (e.g. crop residues, dung and dedicated energy crops). The economic mitigation potential of biomass energy from agriculture is estimated to be 640, 2240 and 16 000 Mt CO2-eq. yr−1 at 0–20, 0–50 and 0–100 US$ t CO2-eq.−1, respectively.

    References

    • Albrecht A& Kandji S.T. 2003Carbon sequestration in tropical agroforestry systems. Agric. Ecosyst. Environ. 99, 15–27.doi:10.1016/S0167-8809(03)00138-5. . Crossref, ISIGoogle Scholar
    • Alcock, D. & Hegarty, R. S. 2005 Effects of pasture improvement on productivity, gross margin and methane emissions of grazing sheep enterprises. In Second Int. Conf. on Greenhouse Gases and Animal Agriculture, Working Papers (eds C. R. Soliva, J. Takahashi & M. Kreuzer), pp. 127–130. Zurich, Switzerland: ETH. Google Scholar
    • Alvarez R. 2005A review of nitrogen fertilizer and conservative tillage effects on soil organic storage. Soil Use Manage. 21, 38–52.doi:10.1079/SUM2005291. . Crossref, ISIGoogle Scholar
    • Anderson T.L, Charlson R.J, Schwartz S.E, Knutti R, Boucher O, Rodhe H& Heintzenberg J. 2003Climate forcing by aerosols—a hazy picture. Science. 300, 1103–1104.doi:10.1126/science.1084777. . Crossref, PubMed, ISIGoogle Scholar
    • Andreae M.O. 2001The dark side of aerosols. Nature. 409, 671–672.doi:10.1038/35055640. . Crossref, PubMed, ISIGoogle Scholar
    • Andreae M.O& Merlet P. 2001Emission to trace gases and aerosols from biomass burning. Global Biogeochem. Cycles. 15, 955–966.doi:10.1029/2000GB001382. . Crossref, ISIGoogle Scholar
    • Andreae M.O, Jones C.D& Cox P.M. 2005Strong present-day aerosol cooling implies a hot future. Nature. 435, 1187doi:10.1038/nature03671. . Crossref, PubMed, ISIGoogle Scholar
    • Antle J.M, Capalbo S.M, Mooney S, Elliott E.T& Paustian K.H. 2001Economic analysis of agricultural soil carbon sequestration: an integrated assessment approach. J. Agric. Resour. Econ. 26, 344–367. ISIGoogle Scholar
    • Aulakh M.S, Wassmann R, Bueno C& Rennenberg H. 2001Impact of root exudates of different cultivars and plant development stages of rice (Oryza sativa L.) on methane production in a paddy soil. Plant Soil. 230, 77–86.doi:10.1023/A:1004817212321. . Crossref, ISIGoogle Scholar
    • Barthès B, Azontonde A, Blanchart E, Girardin C, Villenave C, Lesaint S, Oliver R& Feller C. 2004Effect of a legume cover crop (Mucuna pruriens var. utilis) on soil carbon in an Ultisol under maize cultivation in southern Benin. Soil Use Manage. 20, 231–239.doi:10.1079/SUM2004235. . Crossref, ISIGoogle Scholar
    • Batjes, N. H. 1999 Management options for reducing CO2-concentrations in the atmosphere by increasing carbon sequestration in the soil. Dutch National Research Programme on Global Air Pollution and Climate Change report 410-200-031 and ISRIC technical paper 30, International Soil Reference and Information Centre, Wageningen, The Netherlands. Google Scholar
    • Bauman D.E. 1992Bovine somatotropin: review of an emerging animal technology. J. Dairy Sci. 75, 3432–3451. Crossref, PubMed, ISIGoogle Scholar
    • Beauchemin K& McGinn S. 2005Methane emissions from feedlot cattle fed barley or corn diets. J. Anim. Sci. 83, 653–661. Crossref, PubMed, ISIGoogle Scholar
    • Benz D.A& Johnson D.E. 1982The effect of monensin on energy partitioning by forage fed steers. Proc. West Section Am. Soc. Anim. Sci. 33, 60. Google Scholar
    • Beringer J, Hutley L.B, Tapper N.J, Coutts A, Kerley A& O'Grady A.P. 2003Fire impacts on surface heat, moisture and carbon fluxes from a tropical savanna in northern Australia. Int. J. Wildland Fire. 12, 333–340.doi:10.1071/WF03023. . Crossref, ISIGoogle Scholar
    • Berndes G, Hoogwijk M& van den Broek R. 2003The contribution of biomass in the future global energy supply: a review of 17 studies. Biomass Bioenergy. 25, 1–28.doi:10.1016/S0961-9534(02)00185-X. . Crossref, ISIGoogle Scholar
    • Blaxter K.L& Clapperton J.L. 1965Prediction of the amount of methane produced by ruminants. Br. J. Nutr. 19, 511–522.doi:10.1079/BJN19650046. . Crossref, PubMed, ISIGoogle Scholar
    • Boadi D, Benchaar C, Chiquette J& Massé D. 2004Mitigation strategies to reduce enteric methane emissions from dairy cows: update review. Can. J. Anim. Sci. 84, 319–335. Crossref, ISIGoogle Scholar
    • Boehm M, Junkins B, Desjardins R, Kulshreshtha S& Lindwall W. 2004Sink potential of Canadian agricultural soils. Clim. Change. 65, 297–314.doi:10.1023/B:CLIM.0000038205.09327.51. . Crossref, ISIGoogle Scholar
    • Bouwman AGlobal estimates of gaseous emissions from agricultural land. 2001Rome, Italy:FAO. Google Scholar
    • Bruce J.P, Frome M, Haites E, Janzen H, Lal R& Paustian K. 1999Carbon sequestration in soils. J. Soil Water Conserv. 54, 382–389. ISIGoogle Scholar
    • Cai Z.C& Xu HOptions for mitigating CH4 emissions from rice fields in China. Material circulation through agro-ecosystems in East Asia and assessment of its environmental impact. & Hayashi YNIAES Series, no. 52004pp. 45–55. Eds. Tsukuba, Japan:NIAES. Google Scholar
    • Cai Z.C, Tsuruta H& Minami K. 2000Methane emissions from rice fields in China: measurements and influencing factors. J. Geophys. Res. 105, 17 231–17 242.doi:10.1029/2000JD900014. . Crossref, ISIGoogle Scholar
    • Cai Z.C, Tsuruta H, Gao M, Xu H& Wei C.F. 2003Options for mitigating methane emission from a permanently flooded rice field. Global Change Biol. 9, 37–45.doi:10.1046/j.1365-2486.2003.00562.x. . Crossref, ISIGoogle Scholar
    • Caldeira K, Morgan M.G, Baldocchi D, Brewer P.G, Chen C.T.A, Nabuurs G.J, Nakicenovic N& Robertson G.PA portfolio of carbon management options. The global carbon cycle. Integrating humans, climate, and the natural world, Field C.B& Raupach M.R. 2004pp. 103–129. Eds. Washington DC:Island Press. Google Scholar
    • Cannell M.G.R. 2003Carbon sequestration and biomass energy offset: theoretical, potential and achievable capacities globally, in Europe and the UK. Biomass Bioenergy. 24, 97–116.doi:10.1016/S0961-9534(02)00103-4. . Crossref, ISIGoogle Scholar
    • Cassman K.G, Dobermann A, Walters D.T& Yang H. 2003Meeting cereal demand while protecting natural resources and improving environmental quality. Annu. Rev. Environ. Resour. 28, 315–358.doi:10.1146/annurev.energy.28.040202.122858. . Crossref, ISIGoogle Scholar
    • Cerri C.C, Bernoux M, Cerri C.E.P& Feller C. 2004Carbon cycling and sequestration opportunities in South America: the case of Brazil. Soil Use Manage. 20, 248–254.doi:10.1079/SUM2004237. . Crossref, ISIGoogle Scholar
    • Chadwick D.R. 2005Emissions of ammonia, nitrous oxide and methane from cattle manure heaps: effect of compaction and covering. Atmos. Environ. 39, 787–799.doi:10.1016/j.atmosenv.2004.10.012. . Crossref, ISIGoogle Scholar
    • Clark H, Pinares C& de Klein CMethane and nitrous oxide emissions from grazed grasslands. Grassland—a global resource& McGilloway D. 2005pp. 279–293. Eds. Wageningen, The Netherlands:Wageningen Academic Publishers. Google Scholar
    • Clemens J& Ahlgrimm H.J. 2001Greenhouse gases from animal husbandry: mitigation options. Nutr. Cycl. Agroecosyst. 60, 287–300.doi:10.1023/A:1012712532720. . Crossref, ISIGoogle Scholar
    • Clemens J, Trimborn M, Weiland P& Amon B. 2006Mitigation of greenhouse gas emissions by anaerobic digestion of cattle slurry. Agric. Ecosyst. Environ. 112, 171–177.doi:10.1016/j.agee.2005.08.016. . Crossref, ISIGoogle Scholar
    • Cole C.V, et al.1997Global estimates of potential mitigation of greenhouse gas emissions by agriculture. Nutr. Cycl. Agroecosyst. 49, 221–228.doi:10.1023/A:1009731711346. . Crossref, ISIGoogle Scholar
    • Conant R.T& Paustian K. 2002Potential soil carbon sequestration in overgrazed grassland ecosystems. Global Biogeochem. Cycles. 16, 90-1–90-9.doi:10.1029/2001GB001661. . Crossref, ISIGoogle Scholar
    • Conant R.T, Paustian K& Elliott E.T. 2001Grassland management and conversion into grassland: effects on soil carbon. Ecol. Appl. 11, 343–355.http://dx.doi:10.1890/1051-0761(2001)011[0343:GMACIG]2.0.CO;2. . Crossref, ISIGoogle Scholar
    • Conant R.T, Paustian K, Del Grosso S.J& Parton W.J. 2005Nitrogen pools and fluxes in grassland soils sequestering carbon. Nutr. Cycl. Agroecosyst. 71, 239–248.doi:10.1007/s10705-004-5085-z. . Crossref, ISIGoogle Scholar
    • Crutzen, P. J. 1995 The role of methane in atmospheric chemistry and climate. In Ruminant Physiology: Digestion, Metabolism, Growth and Reproduction Proc. Eighth Int. Symp. on Ruminant Physiology (eds W. Von Engelhardt, S. Leonhard-Marek, G. Breves, & D. Giesecke), pp. 291–316. Stuttgart, Germany: Ferdinand Enke Verlag. Google Scholar
    • Dalal R.C, Wang W, Robertson G.P& Parton W.J. 2003Nitrous oxide emission from Australian agricultural lands and mitigation options: a review. Aust. J. Soil Res. 41, 165–195.doi:10.1071/SR02064. . Crossref, ISIGoogle Scholar
    • Davidson E.A, Nepstad D.C, Klink C& Trumbore S.E. 1995Pasture soils as carbon sink. Nature. 376, 472–473.doi:10.1038/376472a0. . Crossref, ISIGoogle Scholar
    • Derner J.D, Boutton T.W& Briske D.D. 2006Grazing and ecosystem carbon storage in the North American Great Plains. Plant Soil. 280, 77–90.doi:10.1007/s11104-005-2554-3. . Crossref, ISIGoogle Scholar
    • Dias de Oliveira M.E, Vaughan B.E& Rykiel E.J. 2005Ethanol as fuel: energy, carbon dioxide balances, and ecological footprint. BioScience. 55, 593–602.doi:10.1641/0006-3568(2005)055[0593:EAFECD]2.0.CO;2. . Crossref, ISIGoogle Scholar
    • Dohme F.A, Machmuller A, Wasserfallen A& Kreuzer M. 2000Comparative efficiency of various fats rich in medium-chain fatty acids to suppress ruminal methanogenesis as measured with Rusitec. Can. J. Anim. Sci. 80, 473–482. Crossref, ISIGoogle Scholar
    • Edmonds J.A. 2004Climate change and energy technologies. Mitig. Adapt. Strat. Global Change. 9, 391–416.doi:10.1023/B:MITI.0000038846.11924.5f. . CrossrefGoogle Scholar
    • Eidman V.RAgriculture as a producer of energy. Agriculture as a producer and consumer of energy, Outlaw J.L, Collins K.J& Duffield J.A. 2005pp. 30–67. Eds. Wallingford, UK:CAB International. CrossrefGoogle Scholar
    • Faaij A.P.C. 2006Modern biomass conversion technologies. Mitig. Adapt. Strat. Global Change. 11, 335–367.doi:10.1007/s11027-005-9004-7. . CrossrefGoogle Scholar
    • Falloon P, Smith P& Powlson D.S. 2004Carbon sequestration in arable land—the case for field margins. Soil Use Manage. 20, 240–247.doi:10.1079/SUM2004236. . Crossref, ISIGoogle Scholar
    • FAO/IIASA 2000 Global Agro-Ecological Zones Database. http://www.fao.org/ag/agl/agll/gaez/index.htm. Google Scholar
    • FAOSTAT 2006 FAOSTAT agricultural data. See http://faostat.fao.org/faostat/collections?version=ext&hasbulk=0&subset=agriculture. Google Scholar
    • FAO/UNESCO 2002 FAO digital soils map of the world. On CD. See http://www.fao.org/ag/agl/agll/dsmw.stm. Google Scholar
    • Ferris C.P, Gordon F.J, Patterson D.C, Porter M.G& Yan T. 1999The effect of genetic merit and concentrate proportion in the diet on nutrient utilization by lactating dairy cows. J. Agric. Sci. Camb. 132, 483–490.doi:10.1017/S0021859699006553. . Crossref, ISIGoogle Scholar
    • Fisher M.J, Rao I.M, Ayarza M.A, Lascano C.E, Sanz J.I, Thomas R.J& Vera R.R. 1994Carbon storage by introduced deep-rooted grasses in the South American savannas. Nature. 371, 236–238.doi:10.1038/371236a0. . Crossref, ISIGoogle Scholar
    • Foley J.A, et al.2005Global consequences of land use. Science. 309, 570–574.doi:10.1126/science.1111772. . Crossref, PubMed, ISIGoogle Scholar
    • Follett R.FOrganic carbon pools in grazing land soils. The potential of U.S. grazing lands to sequester carbon and mitigate the greenhouse effect, Follett R.F, Kimble J.M& Lal R. 2001pp. 65–86. Eds. Boca Raton, FL:Lewis. Google Scholar
    • Follett R.F, Kimble J.M& Lal RThe potential of U.S. grazing lands to sequester soil carbon. The potential of U.S. grazing lands to sequester carbon and mitigate the greenhouse effect, Follett R.F, Kimble J.M& Lal R. 2001pp. 401–430. Eds. Boca Raton, FL:Lewis. Google Scholar
    • Freibauer A, Rounsevell M, Smith P& Verhagen A. 2004Carbon sequestration in the agricultural soils of Europe. Geoderma. 122, 1–23.doi:10.1016/j.geoderma.2004.01.021. . Crossref, ISIGoogle Scholar
    • Galloway J.N, Aber J.D, Erisman J.W, Seitzinger S.P, Howarth R.W, Cowling E.B& Cosby B.J. 2003The nitrogen cascade. Bioscience. 53, 341–356.doi:10.1641/0006-3568(2003)053[0341:TNC]2.0.CO;2. . Crossref, ISIGoogle Scholar
    • Gonzalez-Avalos E& Ruiz-Suarez L.G. 2001Methane emission factors from cattle in Mexico. Bioresour. Technol. 80, 63–71.doi:10.1016/S0960-8524(01)00052-9. . Crossref, PubMed, ISIGoogle Scholar
    • Gregorich E.G, Rochette P, VandenBygaart A.J& Angers D.A. 2005Greenhouse gas contributions of agricultural soils and potential mitigation practices in eastern Canada. Soil Till. Res. 83, 53–72.doi:10.1016/j.still.2005.02.009. . Crossref, ISIGoogle Scholar
    • Guo L.B& Gifford R.M. 2002Soil carbon stocks and land use change: a meta analysis. Global Change Biol. 8, 345–360.doi:10.1046/j.1354-1013.2002.00486.x. . Crossref, ISIGoogle Scholar
    • Hamelinck C.N, Suurs R.A.A& Faaij A.P.C. 2004Techno-economic analysis of international bio-energy trade chains. Biomass Bioenergy. 29, 114–134.doi:10.1016/j.biombioe.2005.04.002. . Crossref, ISIGoogle Scholar
    • Hansen L.B. 2000Consequences of selection for milk yield from a geneticist's viewpoint. J. Dairy Sci. 83, 1145–1150. Crossref, PubMed, ISIGoogle Scholar
    • Helgason B.L, et al.2005Toward improved coefficients for predicting direct N2O emissions from soil in Canadian agroecosystems. Nutr. Cycl. Agroecosyst. 71, 87–99.doi:10.1007/s10705-004-7358-y. . Crossref, ISIGoogle Scholar
    • Hoogwijk, M. 2004 On the global and regional potential of renewable energy sources. PhD thesis, Copernicus Institute, Utrecht University. Google Scholar
    • Hoogwijk M, Faaij A, Eickhout B, de Vries B& Turkenburg W. 2005Potential of biomass energy out to 2100, for four IPCC SRES land-use scenarios. Biomass Bioenergy. 29, 225–257.doi:10.1016/j.biombioe.2005.05.002. . Crossref, ISIGoogle Scholar
    • International Panel on Climate Change (IPCC)Climate change 1995: the science of climate change. Contribution of working group I to the 2nd assessment report of the IPCC. 1996Cambridge, UK:Cambridge University Press. Google Scholar
    • International Panel on Climate Change (IPCC) vol. 21997Cambridge, UK:Cambridge University Press. Google Scholar
    • International Panel on Climate Change (IPCC)Special report on land use, land-use change and forestry. 2000Cambridge, UK:Cambridge University Press. Google Scholar
    • International Panel on Climate Change (IPCC)Climate change 2001: the scientific basis. Contribution of working group I to the third assessment report of the intergovernmental panel on climate change. 2001Cambridge, UK:Cambridge University Press. Google Scholar
    • International Panel on Climate Change (IPCC)Good practice guidelines for greenhouse gas inventories for land-use, land-use change & forestry. 2003Kanagawa, Japan:Institute of Global Environmental Strategies (IGES). Google Scholar
    • Izaurralde R.C, McGill W.B, Robertson J.A, Juma N.G& Thurston J.J. 2001Carbon balance of the Breton Classical plots over half a century. Soil Sci. Soc. Am. J. 65, 431–441. Crossref, ISIGoogle Scholar
    • Janzen H.H. 2004Carbon cycling in earth systems—a soil science perspective. Agric. Ecosyst. Environ. 104, 399–417.doi:10.1016/j.agee.2004.01.040. . Crossref, ISIGoogle Scholar
    • Johnson K.A& Johnson D.E. 1995Methane emissions from cattle. J. Anim. Sci. 73, 2483–2492. Crossref, PubMed, ISIGoogle Scholar
    • Johnson D.E, Ward G.M& Torrent J. 1991The environmental impact of bovine somatotropin (bST) use in dairy cattle. J. Dairy Sci. 74, 209. Google Scholar
    • Johnson D.E, Phetteplace H.W& Seidl A.FMethane, nitrous oxide and carbon dioxide emissions from ruminant livestock production systems. Greenhouse gases and animal agriculture, Takahashi J& Young B.A. 2002pp. 77–85. Eds. Amsterdam, The Netherlands:Elsevier. Google Scholar
    • Jones C.D, Cox P.M, Essery R.L.H, Roberts D.L& Woodage M.J. 2003Strong carbon cycle feedbacks in a climate model with interactive CO2 and sulphate aerosols. Geophys. Res. Lett. 30, 321–324. Crossref, ISIGoogle Scholar
    • Jordan, E. Lovett, D. K. Hawkins, M. & O'Mara, F. P. 2004 The effect of varying levels of coconut oil on methane output from continental cross beef heifers. In Proc. Int. Conf. on Greenhouse Gas Emissions from Agriculture—Mitigation Options and Strategies (ed. A. Weiske), pp. 124–130. Leipzig, Germany: Institute for Energy and Environment. Google Scholar
    • Jordan E, Lovett D.K, Monahan F.J& O'Mara F.PEffect of refined coconut oil or copra meal on methane output, intake and performance of beef heifers. J. Anim Sci. 84, 2006a162–170. Crossref, PubMed, ISIGoogle Scholar
    • Jordan E, Kenny D, Hawkins M, Malone R, Lovett D.K& O'Mara F.PEffect of refined soy oil or whole soybeans on methane output, intake and performance of young bulls. J. Anim. Sci. 84, 2006b2418–2425.doi:10.2527/jas.2005-354. . Crossref, PubMed, ISIGoogle Scholar
    • Junginger M, Faaij A, Koopmans A, van den Broek R& Hulscher W. 2001Setting up fuel supply strategies for large scale bio-energy projects—a methodology for developing countries. Biomass Bioenergy. 21, 259–275.doi:10.1016/S0961-9534(01)00034-4. . Crossref, ISIGoogle Scholar
    • Kang G.D, Cai Z.C& Feng X.Z. 2002Importance of water regime during the non-rice growing period in winter in regional variation of CH4 emissions from rice fields during following rice growing period in China. Nutr. Cycl. Agroecosyst. 64, 95–100.doi:10.1023/A:1021154932643. . Crossref, ISIGoogle Scholar
    • Kasimir-Klemedtsson A, Klemedtsson L, Berglund K, Martikainen P, Silvola J& Oenema O. 1997Greenhouse gas emissions from farmed organic soils: a review. Soil Use Manage. 13, 245–250.doi:10.1111/j.1475-2743.1997.tb00595.x. . Crossref, ISIGoogle Scholar
    • Kennedy P.M& Milligan L.P. 1978Effects of cold exposure on digestion, microbial synthesis and nitrogen transformation in sheep. Br. J. Nutr. 39, 105–117.doi:10.1079/BJN19780017. . Crossref, PubMed, ISIGoogle Scholar
    • Korontzi S, Justice C.O& Scholes R.J. 2003Influence of timing and spatial extent of savanna fires in southern Africa on atmospheric emissions. J. Arid Environ. 54, 395–404.doi:10.1006/jare.2002.1098. . Crossref, ISIGoogle Scholar
    • Külling D.R, Menzi H, Sutter F, Lischer P& Kreuzer M. 2003Ammonia, nitrous oxide and methane emissions from differently stored dairy manure derived from grass- and hay-based rations. Nutr. Cycl. Agroecosyst. 65, 13–22.doi:10.1023/A:1021857122265. . Crossref, ISIGoogle Scholar
    • Lal R. 1999Soil management and restoration for C sequestration to mitigate the accelerated greenhouse effect. Prog. Environ. Sci. 1, 307–326. Google Scholar
    • Lal R. 2001Potential of desertification control to sequester carbon and mitigate the greenhouse effect. Clim. Change. 15, 35–72.doi:10.1023/A:1017529816140. . Crossref, ISIGoogle Scholar
    • Lal R. 2003Global potential of soil carbon sequestration to mitigate the greenhouse effect. Crit. Rev. Plant Sci. 22, 151–184.doi:10.1080/713610854. . Crossref, ISIGoogle Scholar
    • Lal RSoil carbon sequestration impacts on global climate change and food security. Science. 304, 2004a1623–1627.doi:10.1126/science.1097396. . Crossref, PubMed, ISIGoogle Scholar
    • Lal RSoil carbon sequestration to mitigate climate change. Geoderma. 123, 2004b1–22.doi:10.1016/j.geoderma.2004.01.032. . Crossref, ISIGoogle Scholar
    • Lal ROffsetting China's CO2 emissions by soil carbon sequestration. Clim. Change. 65, 2004c263–275.doi:10.1023/B:CLIM.0000038203.81854.7c. . Crossref, ISIGoogle Scholar
    • Lal RCarbon sequestration in soils of central Asia. Land Degrad. Dev. 15, 2004d563–572.doi:10.1002/ldr.624. . Crossref, ISIGoogle Scholar
    • Lal RSoil carbon sequestration in India. Clim. Change. 65, 2004e277–296.doi:10.1023/B:CLIM.0000038202.46720.37. . Crossref, ISIGoogle Scholar
    • Lal R. 2005Soil carbon sequestration for sustaining agricultural production and improving the environment with particular reference to Brazil. J. Sustain. Agric. 26, 23–42.doi:10.1300/J064v26n02_04. . Crossref, ISIGoogle Scholar
    • Lal R& Bruce J.P. 1999The potential of world cropland soils to sequester C and mitigate the greenhouse effect. Environ. Sci. Policy. 2, 177–185.doi:10.1016/S1462-9011(99)00012-X. . CrossrefGoogle Scholar
    • Lal R, Follett R.F& Kimble J.M. 2003Achieving soil carbon sequestration in the United States: a challenge to the policy makers. Soil Sci. 168, 827–845.doi:10.1097/01.ss.0000106407.84926.6b. . Crossref, ISIGoogle Scholar
    • Lee H.-C, McCarl B.A& Gillig D. 2005The dynamic competitiveness of U.S. agricultural and forest carbon sequestration. Can. J. Agric. Econ. 53, 343–357.doi:10.1111/j.1744-7976.2005.00023.x. . Crossref, ISIGoogle Scholar
    • Le Mer J& Roger P. 2001Production, oxidation, emission and consumption of methane by soils: a review. Eur. J. Soil Biol. 37, 25–50.doi:10.1016/S1164-5563(01)01067-6. . Crossref, ISIGoogle Scholar
    • Leng, R. A. 1991 Improving ruminant production and reducing methane emissions from ruminants by strategic supplementation. EPA report, no. 400/1-91/004. US Environmental Protection Agency, Washington, DC. Google Scholar
    • Li C, Frolking S& Butterbach-Bahl K. 2005Carbon sequestration in arable soils is likely to increase nitrous oxide emissions, offsetting reductions in climate radiative forcing. Clim. Change. 72, 321–338.doi:10.1007/s10584-005-6791-5. . Crossref, ISIGoogle Scholar
    • Liebig M.A, Morgan J.A, Reeder J.D, Ellert B.H, Gollany H.T& Schuman G.E. 2005Greenhouse gas contributions and mitigation potential of agricultural practices in northwestern USA and western Canada. Soil Till. Res. 83, 25–52.doi:10.1016/j.still.2005.02.008. . Crossref, ISIGoogle Scholar
    • Lovett D.K& O'Mara F.P. 2002Estimation of enteric methane emissions originating from the national livestock beef herd: a review of the IPCC default emission factors. Tearmann. 2, 77–83. Google Scholar
    • Lovett D, Lovell S, Stack L, Callan J, Finlay M, Connolly J& O'Mara F.P. 2003Effect of forage/concentrate ratio and dietary coconut oil level on methane output and performance of finishing beef heifers. Livest. Prod. Sci. 84, 135–146.doi:10.1016/j.livprodsci.2003.09.010. . CrossrefGoogle Scholar
    • Lovett D.K, Shalloo L, Dillon P& O'Mara F.P. 2006A systems approach to quantify greenhouse gas fluxes from pastoral dairy production as affected by management regime. Agric. Syst. 88, 156–179.doi:10.1016/j.agsy.2005.03.006. . Crossref, ISIGoogle Scholar
    • Machmülller A, Ossowski D.A& Kreuzer M. 2000Comparative evaluation of the effects of coconut oil, oilseeds and crystalline fat on methane release, digestion and energy balance in lambs. Anim. Feed Sci. Technol. 85, 41–60.doi:10.1016/S0377-8401(00)00126-7. . Crossref, ISIGoogle Scholar
    • Machmüller A, Soliva C.R& Kreuzer M. 2003Methane-suppressing effect of myristic acid in sheep as affected by dietary calcium and forage proportion. Br. J. Nutr. 90, 529–540.doi:10.1079/BJN2003932. . Crossref, PubMed, ISIGoogle Scholar
    • Manne A.S& Richels R.GA multi-gas approach to climate policy. The global carbon cycle. Integrating humans, climate, and the natural world, Field C.B& Raupach M.R. 2004pp. 439–452. Eds. Washington, DC:Island Press. Google Scholar
    • Marland G, McCarl B.A& Schneider U.A. 2001Soil carbon: policy and economics. Clim. Change. 51, 101–117.doi:10.1023/A:1017575018866. . Crossref, ISIGoogle Scholar
    • Marland G, et al.The climatic impacts of land surface change and carbon management, and the implications for climate-change mitigation policy. Climate Policy. 3, 2003a149–157.doi:10.1016/S1469-3062(03)00028-7. . Crossref, ISIGoogle Scholar
    • Marland G, West T.O, Schlamadinger B& Canella LManaging soil organic carbon in agriculture: the net effect on greenhouse gas emissions. Tellus B. 55, 2003b613–621.doi:10.1034/j.1600-0889.2003.00054.x. . CrossrefGoogle Scholar
    • McCarl B.A& Schneider U.A. 2001Greenhouse gas mitigation in U.S. agriculture and forestry. Science. 294, 2481–2482.doi:10.1126/science.1064193. . Crossref, PubMed, ISIGoogle Scholar
    • McCaughney W.P, Wittenberg K& Corrigan D. 1999Impact of pasture type on methane production by lactating cows. Can. J. Anim. Sci. 79, 221–226. Crossref, ISIGoogle Scholar
    • McCrabb G.CNutritional options for abatement of methane emissions from beef and dairy systems in Australia. Greenhouse gases and animal agriculture, Takahashi J& Young B.A. 2001pp. 115–124. Eds. Amsterdam, The Netherlands:Elsevier. Google Scholar
    • McCrabb G.J, Kurihara M& Hunter R.A. 1998The effect of finishing strategy of lifetime methane production for beef cattle in northern Australia. Proc. Nutr. Soc. Aust. 22, 55. Google Scholar
    • McGinn S.M, Beauchemin K.A, Coates T& Colombatto D. 2004Methane emissions from beef cattle: effects of monensin, sunflower oil, enzymes, yeast, and fumaric acid. J. Anim. Sci. 82, 3346–3356. Crossref, PubMed, ISIGoogle Scholar
    • Menon S, Hansen J, Nazarenko L& Luo Y. 2002Climate effects of black carbon aerosols in China and India. Science. 297, 2250–2253.doi:10.1126/science.1075159. . Crossref, PubMed, ISIGoogle Scholar
    • Miglior F, Muir B.L& Van Doormaal B.J. 2005Selection indices in Holstein cattle of various countries. J. Dairy Sci. 88, 1255–1263. Crossref, PubMed, ISIGoogle Scholar
    • Millennium Ecosystem AssessmentFindings from the conditions and trend working group. 2005Washington, DC:Island Press. Google Scholar
    • Mills J.A.N, Kebreab E, Yates C.M, Crompton L.A, Cammell S.B, Dhanoa M.S, Agnew R.E& France J. 2003Alternative approaches to predicting methane emissions from dairy cows. J. Anim. Sci. 81, 3141–3150. Crossref, PubMed, ISIGoogle Scholar
    • Moe P.W& Tyrrell H.F. 1979Methane production in dairy cows. J. Dairy Sci. 62, 1583–1586. Crossref, ISIGoogle Scholar
    • Monteny G.J, Groenestein C.M& Hilhorst M.A. 2001Interactions and coupling between emissions of methane and nitrous oxide from animal husbandry. Nutr. Cycl. Agroecosyst. 60, 123–132.doi:10.1023/A:1012602911339. . Crossref, ISIGoogle Scholar
    • Monteny G.-J, Bannink A& Chadwick D. 2006Greenhouse gas abatement strategies for animal husbandry. Agric. Ecosyst. Environ. 112, 163–170.doi:10.1016/j.agee.2005.08.015. . Crossref, ISIGoogle Scholar
    • Mosier A.R, Duxbury J.M, Freney J.R, Heinemeyer O, Minami K& Johnson D.E. 1998Mitigating agricultural emissions of methane. Clim. Change. 40, 39–80.doi:10.1023/A:1005338731269. . Crossref, ISIGoogle Scholar
    • Mosier A.R, Halvorson A.D, Peterson G.A, Robertson G.P& Sherrod L. 2005Measurement of net global warming potential in three agroecosystems. Nutr. Cycl. Agroecosyst. 72, 67–76.doi:10.1007/s10705-004-7356-0. . Crossref, ISIGoogle Scholar
    • Murray R.M, Bryant A.M& Leng R.A. 1976Rate of production of methane in the rumen and the large intestine of sheep. Br. J. Nutr. 36, 1–14.doi:10.1079/BJN19760053. . Crossref, PubMed, ISIGoogle Scholar
    • Mutuo P.K, Cadisch G, Albrecht A, Palm C.A& Verchot L. 2005Potential of agroforestry for carbon sequestration and mitigation of greenhouse gas emissions from soils in the tropics. Nutr. Cycl. Agroecosyst. 71, 43–54.doi:10.1007/s10705-004-5285-6. . Crossref, ISIGoogle Scholar
    • Newbold, C. J. & Rode, L. M. 2005 Dietary additives to control methanogenesis in the rumen. In Second Int. Conf. on Greenhouse Gases and Animal Agriculture, Working Papers (eds C. R. Soliva, J. Takahashi, & M. Kreuzer), pp. 60–70. Zurich, Switzerland: ETH. Google Scholar
    • Newbold C.J, Ouda J.O, Lopez S, Nelson N, Omed H, Wallace R.J& Moss A.RPropionate precursors as possible alternative electron acceptors to methane in ruminal fermentation. Greenhouse gases and animal agriculture, Takahashi J& Young B.A. 2002pp. 151–154. Eds. Amsterdam, The Netherlands:Elsevier. Google Scholar
    • Newbold C.J, López S, Nelson N, Ouda J.O, Wallace R.J& Moss A.R. 2005Propionate precursors and other metabolic intermediates as possible alternative electron acceptors to methanogenesis in ruminal fermentation in vitro. Br. J. Nutr. 94, 27–35.doi:10.1079/BJN20051445. . Crossref, PubMed, ISIGoogle Scholar
    • Oelbermann M, Voroney R.P& Gordon A.M. 2004Carbon sequestration in tropical and temperate agroforestry systems: a review with examples from Costa Rica and southern Canada. Agric. Ecosyst. Environ. 104, 359–377.doi:10.1016/j.agee.2004.04.001. . Crossref, ISIGoogle Scholar
    • Oenema O, Wrage N, Velthof G.L, van Groenigen J.W, Dolfing J& Kuikman P.J. 2005Trends in global nitrous oxide emissions from animal production systems. Nutr. Cycl. Agroecosyst. 72, 51–65.doi:10.1007/s10705-004-7354-2. . Crossref, ISIGoogle Scholar
    • Ogle S.M, Breidt F.J, Eve M.D& Paustian K. 2003Uncertainty in estimating land use and management impacts on soil organic storage for US agricultural lands between 1982 and 1997. Global Change Biol. 9, 1521–1542.doi:10.1046/j.1365-2486.2003.00683.x. . Crossref, ISIGoogle Scholar
    • Ogle S.M, Breidt F.J& Paustian K. 2005Agricultural management impacts on soil organic carbon storage under moist and dry climatic conditions of temperate and tropical regions. Biogeochemistry. 72, 87–121.doi:10.1007/s10533-004-0360-2. . Crossref, ISIGoogle Scholar
    • Olsson L& Ardo J. 2002Soil carbon sequestration in degraded semiarid agro-ecosystems—perils and potentials. Ambio. 31, 471–477.doi:10.1639/0044-7447(2002)031[0471:SCSIDS]2.0.CO;2. . Crossref, PubMed, ISIGoogle Scholar
    • Pattey E, Trzcinski M.K& Desjardins R.L. 2005Quantifying the reduction of greenhouse gas emissions as a result of composting dairy and beef cattle manure. Nutr. Cycl. Agroecosyst. 72, 173–187.doi:10.1007/s10705-005-1268-5. . Crossref, ISIGoogle Scholar
    • Paul E.A, Morris S.J, Six J, Paustian K& Gregorich E.G. 2003Interpretation of soil carbon and nitrogen dynamics in agricultural and afforested soils. Soil Sci. Soc. Am. J. 67, 1620–1628. Crossref, ISIGoogle Scholar
    • Paustian K, Cole C.V, Sauerbeck D& Sampson N. 1998CO2 mitigation by agriculture: an overview. Clim. Change. 40, 135–162.doi:10.1023/A:1005347017157. . Crossref, ISIGoogle Scholar
    • Paustian, K. et al. 2004. Agricultural mitigation of greenhouse gases: science and policy options. Council on Agricultural Science and Technology (CAST) report, R141 2004, ISBN 1-887383-26-3, p. 120, May, 2004. Google Scholar
    • Phetteplace H.W, Johnson D.E& Seidl A.F. 2001Greenhouse gas emissions from simulated beef and dairy livestock systems in the United States. Nutr. Cycl. Agroecosyst. 60, 9–102.doi:10.1023/A:1012657230589. . Crossref, ISIGoogle Scholar
    • Pinares-Patino C.S, Ulyatt M.J, Waghorn G.C, Holmes C.W, Barry T.N, Lassey K.R& Johnson D.E. 2003Methane emission by alpaca and sheep fed on lucerne hay or grazed on pastures of perennial ryegrass/white clover or birdsfoot trefoil. J. Agric. Sci. 140, 215–226.doi:10.1017/S002185960300306X. . Crossref, ISIGoogle Scholar
    • Reay D.S, Smith K.A& Edwards A.C. 2003Nitrous oxide emission from agricultural drainage waters. Global Change Biol. 9, 195–203.doi:10.1046/j.1365-2486.2003.00584.x. . Crossref, ISIGoogle Scholar
    • Reeder J.D, Schuman G.E, Morgan J.A& Lecain D.R. 2004Response of organic and inorganic carbon and nitrogen to long-term grazing of the shortgrass steppe. Environ. Manage. 33, 485–495.doi:10.1007/s00267-003-9106-5. . Crossref, PubMed, ISIGoogle Scholar
    • Rice C.W& Owensby C.EEffects of fire and grazing on soil carbon in rangelands. The potential of U.S. grazing lands to sequester carbon and mitigate the greenhouse effect, Follet R, Kimble J.M& Lal R. 2001pp. 323–342. Eds. Boca Raton, FL:Lewis. Google Scholar
    • Richter B. 2004Using ethanol as an energy source. Science. 305, 340doi:10.1126/science.305.5682.340b. . Crossref, PubMed, ISIGoogle Scholar
    • Robertson G.PAbatement of nitrous oxide, methane and other non-CO2 greenhouse gases: the need for a systems approach. The global carbon cycle. Integrating humans, climate, and the natural world, Field C.B& Raupach M.R. 2004pp. 493–506. Eds. Washington, DC:Island Press. Google Scholar
    • Robertson G.P& Grace P.R. 2004Greenhouse gas fluxes in tropical and temperate agriculture: the need for a full-cost accounting of global warming potentials. Environ. Dev. Sustain. 6, 51–63.doi:10.1023/B:ENVI.0000003629.32997.9e. . CrossrefGoogle Scholar
    • Robertson L.J& Waghorn G.C. 2002Dairy industry perspectives on methane emissions and production from cattle fed pasture or total mixed rations in New Zealand. Proc. New Zeal. Soc. Anim. Prod. 62, 213–218. Google Scholar
    • Robertson G.P, Paul E.A& Harwood R.R. 2000Greenhouse gases in intensive agriculture: contributions of individual gases to the radiative forcing of the atmosphere. Science. 289, 1922–1925.doi:10.1126/science.289.5486.1922. . Crossref, PubMed, ISIGoogle Scholar
    • Rochette P& Janzen H.H. 2005Towards a revised coefficient for estimating N2O emissions from legumes. Nutr. Cycl. Agroecosyst. 73, 171–179.doi:10.1007/s10705-005-0357-9. . Crossref, ISIGoogle Scholar
    • Rogner H, et al.Energy resources. World energy assessment of the United Nations, UNDP, UNDESA/WEC. & Goldemberg JCh. 52000pp. 135–171. Eds. New York, NY:UNDP. Google Scholar
    • Rosegrant, M., Paisner, M. S., Meijer, S. & Witcover, J. 2001 Global food projections to 2020. Emerging trends and alternative futures. Washington, DC: IFPRI Publications. ISBN 0-89629-640-7. See http://www.ifpri.org/pubs/books/globalfoodprojections2020.htm. Google Scholar
    • Rumpler W.V, Johnson D.E& Bates D.B. 1986The effect of high dietary cation concentrations on methanogenesis by steers fed with or without ionophores. J. Anim. Sci. 62, 1737–1741. Crossref, PubMed, ISIGoogle Scholar
    • Schils R.L.M, Verhagen A, Aarts H.F.M& Sebek L.B.J. 2005A farm level approach to define successful mitigation strategies for GHG emissions from ruminant livestock systems. Nutr. Cycl. Agroecosyst. 71, 163–175.doi:10.1007/s10705-004-2212-9. . Crossref, ISIGoogle Scholar
    • Schlesinger W.H. 1999Carbon sequestration in soils. Science. 284, 2095doi:10.1126/science.284.5423.2095. . Crossref, ISIGoogle Scholar
    • Schmidely P. 1993Quantitative review on the use of anabolic hormones in ruminants for meat production. I. Animal performance. Ann. Zootech. 42, 333–359. Crossref, ISIGoogle Scholar
    • Schnabel R.R, Franzluebbers A.J, Stout W.L, Sanderson M.A& Stuedemann J.AThe effects of pasture management practices. The potential of U.S. grazing lands to sequester carbon and mitigate the greenhouse effect, Follett R.F, Kimble J.M& Lal R. 2001pp. 291–322. Eds. Boca Raton, FL:Lewis. Google Scholar
    • Schneider U.A& McCarl B.A. 2003Economic potential of biomass based fuels for greenhouse gas emission mitigation. Environ. Resour. Econ. 24, 291–312.doi:10.1023/A:1023632309097. . Crossref, ISIGoogle Scholar
    • Schneider U.A& McCarl B.A. 2006Implications of a carbon-based energy tax for US agriculture. Agric. Resour. Econ. Rev. 34, 265–278. CrossrefGoogle Scholar
    • Scholes R.J& van der Merwe M.R. 1996Sequestration of carbon in savannas and woodlands. Environ. Prof. 18, 96–103. Google Scholar
    • Schuman G.E, Herrick J.E& Janzen H.HThe dynamics of soil carbon in rangelands. The potential of U.S. grazing lands to sequester carbon and mitigate the greenhouse effect, Follett R.F, Kimble J.M& Lal R. 2001pp. 267–290. Eds. Boca Raton, FL:Lewis. Google Scholar
    • Sheehan J, Aden A, Paustian K, Killian K, Brenner J, Walsh M& Nelson R. 2004Energy and environmental aspects of using corn stover for fuel ethanol. J. Ind. Ecol. 7, 117–146.doi:10.1162/108819803323059433. . CrossrefGoogle Scholar
    • Sims R.E.H, Hastings A, Schlamadinger B, Taylor G& Smith P. 2006Energy crops: current status and future prospects. Global Change Biol. 12, 2054–2076.doi:10.1111/j.1365-2486.2006.01163.x. . Crossref, ISIGoogle Scholar
    • Six J, Ogle S.M, Breidt F.J, Conant R.T, Mosier A.R& Paustian K. 2004The potential to mitigate global warming with no-tillage management is only realized when practised in the long term. Global Change Biol. 10, 155–160.doi:10.1111/j.1529-8817.2003.00730.x. . Crossref, ISIGoogle Scholar
    • Smeets E.M.W, Faaij A.P.C, Lewandowski I.M& Turkenburg W.C. 2007A bottom up quickscan and review of global bio-energy potentials to 2050. Prog. Energy Combust. Sci. 33, 56–106.doi:10.1016/j.pecs.2006.08.001. . Crossref, ISIGoogle Scholar
    • Smith PCarbon sequestration in croplands: the potential in Europe and the global context. Eur. J. Agron. 20, 2004a229–236.doi:10.1016/j.eja.2003.08.002. . Crossref, ISIGoogle Scholar
    • Smith PEngineered biological sinks on land. The global carbon cycle. Integrating humans, climate, and the natural world, Field C.B& Raupach M.R. 2004bpp. 479–491. Eds. Washington, DC:Island Press. Google Scholar
    • Smith K.A& Conen F. 2004Impacts of land management on fluxes of trace greenhouse gases. Soil Use Manage. 20, 255–263.doi:10.1079/SUM2004238. . Crossref, ISIGoogle Scholar
    • Smith P, Powlson D.S, Smith J.U, Falloon P.D& Coleman K. 2000Meeting Europe's climate change commitments: quantitative estimates of the potential for carbon mitigation by agriculture. Global Change Biol. 6, 525–539.doi:10.1046/j.1365-2486.2000.00331.x. . Crossref, ISIGoogle Scholar
    • Smith P, Goulding K.W, Smith K.A, Powlson D.S, Smith J.U, Falloon P.D& Coleman K. 2001Enhancing the carbon sink in European agricultural soils: including trace gas fluxes in estimates of carbon mitigation potential. Nutr. Cycl. Agroecosyst. 60, 237–252.doi:10.1023/A:1012617517839. . Crossref, ISIGoogle Scholar
    • Smith P, Andrén O, Karlsson T, Perälä P, Regina K, Rounsevell M& van Wesemael BCarbon sequestration potential in European croplands has been overestimated. Global Change Biol. 11, 2005a2153–2163.doi:10.1111/j.1365-2486.2005.01052.x. . Crossref, ISIGoogle Scholar
    • Smith J.U, et al.Projected changes in mineral soil carbon of European croplands and grasslands, 1990–2080. Global Change Biol. 11, 2005b2141–2152.doi:10.1111/j.1365-2486.2005.001075.x. . Crossref, ISIGoogle Scholar
    • Smith P, et al.2007Policy and technological constraints to implementation of greenhouse gas mitigation options in agriculture. Agric. Ecosyst. Environ. 118, 6–28.doi:10.1016/j.agee.2006.06.006. . Crossref, ISIGoogle Scholar
    • Soussana J.-F, Loiseau P, Viuchard N, Ceschia E, Balesdent J, Chevallier T& Arrouays D. 2004Carbon cycling and sequestration opportunities in temperate grasslands. Soil Use Manage. 20, 219–230.doi:10.1079/SUM2003234. . Crossref, ISIGoogle Scholar
    • Spatari S, Zhang Y& Maclean H.L. 2005Life cycle assessment of switchgrass- and corn stover-derived ethanol-fueled automobiles. Environ. Sci. Technol. 39, 9750–9758.doi:10.1021/es048293+. . Crossref, PubMed, ISIGoogle Scholar
    • Sperow M, Eve M& Paustian K. 2003Potential soil C sequestration on U.S. agricultural soils. Clim. Change. 57, 319–339.doi:10.1023/A:1022888832630. . Crossref, ISIGoogle Scholar
    • Squires, V., Glenn, E. P. & Ayoub, A. T. 1995 Combating global climate change by combating land degradation. In Proc. Workshop in Nairobi, 4–8 Sept. 1995, p. 348. Nairobi, Kenya: UNEP. Google Scholar
    • Strengers B, Leemans R, Eickhout B, ve Vries B& Bouwman L. 2004The land-use projections and resulting emissions in the IPCC SRES scenarios as simulated by the Image 2.2 model. GeoJournal. 61, 381–393.doi:10.1007/s10708-004-5054-8. . CrossrefGoogle Scholar
    • US-EPA 2006 Global anthropogenic non-CO2 greenhouse gas emissions: 1990–2020, United States Environmental Protection Agency, EPA 430-R-06-003, June 2006. Washington, DC: US-EPA. Google Scholar
    • Van Nevel C.J& Demeyer D.I. 1995Lipolysis and biohydrogenation of soybean oil in the rumen in vitro: inhibition by antimicrobials. J. Dairy Sci. 78, 2797–2806. Crossref, PubMed, ISIGoogle Scholar
    • Van Nevel C.J& Demeyer D.I. 1996Influence of antibiotics and a deaminase inhibitor on volatile fatty acids and methane production from detergent washed hay and soluble starch by rumen microbes in vitro. Anim. Feed Sci. Technol. 37, 21–31.doi:10.1016/0377-8401(92)90117-O. . Crossref, ISIGoogle Scholar
    • van Wilgen B.W, Govender N, Biggs H.C, Ntsala D& Funda X.N. 2004Response of savanna fire regimes to changing fire-management policies in a large African National Park. Conserv. Biol. 18, 1533–1540.doi:10.1111/j.1523-1739.2004.00362.x. . Crossref, ISIGoogle Scholar
    • Venkataraman C, Habib G, Eiguren-Fernandez A, Miguel A.H& Friedlander S.K. 2005Residential biofuels in south Asia: carbonaceous aerosol emissions and climate impacts. Science. 307, 1454–1456.doi:10.1126/science.1104359. . Crossref, PubMed, ISIGoogle Scholar
    • Waghorn G.C, Tavendale M.H& Woodfield D.R. 2002Methanogenesis from forages fed to sheep. Proc. New Zeal. Soc. Anim. Prod. 64, 161–171. Google Scholar
    • Wallace, R. J. Wood, T. A. Rowe, A. Price, J. Yanez, D. R. Williams, S. P. & Newbold, C. J. 2005 Encaspulated fumaric acid as a means of decreasing ruminal methane emissions. In Second Int. Conf. on Greenhouse Gases and Animal Agriculture, Working Papers (eds C. R. Soliva, J. Takahashi & M. Kreuzer), pp. 86–89. Zurich, Switzerland: ETH. Google Scholar
    • Wang M.X& Shangguan X.J. 1996CH4 emission from various rice fields in PR China. Theor. Appl. Climatol. 55, 129–138.doi:10.1007/BF00864708. . Crossref, ISIGoogle Scholar
    • Wassmann R, Lantin R.S, Neue H.U, Buendia L.V, Corton T.M& Lu Y. 2000Characterization of methane emissions from rice fields in Asia. III. Mitigation options and future research needs. Nutr. Cycl. Agroecosyst. 58, 23–36.doi:10.1023/A:1009874014903. . Crossref, ISIGoogle Scholar
    • West T.O& Post W.M. 2002Soil organic carbon sequestration rates by tillage and crop rotation: a global data analysis. Soil Sci. Soc. Am. J. 66, 1930–1946. Crossref, ISIGoogle Scholar
    • Wolin E.A, Wolf R.S& Wolin M.J. 1964Microbial formation of methane. J. Bacteriol. 87, 993–998. Crossref, PubMed, ISIGoogle Scholar
    • Woodward S.L, Waghorn G.C, Ulyatt M.J& Lassey K.R. 2001Early indications that feeding Lotus will reduce methane emissions from ruminants. Proc. New Zeal. Soc. Anim. Prod. 61, 23–26. Google Scholar
    • Wright A.D.G, Kennedy P, O'Neill C.J, Troovey A.F, Popovski S, Rea S.M, Pimm C.L& Klein L. 2004Reducing methane emissions in sheep by immunization against rumen methanogens. Vaccine. 22, 3976–3985.doi:10.1016/j.vaccine.2004.03.053. . Crossref, PubMed, ISIGoogle Scholar
    • Xu H, Cai Z.C, Jia Z.J& Tsuruta H. 2000Effect of land management in winter crop season on CH4 emission during the following flooded and rice-growing period. Nutr. Cycl. Agroecosyst. 58, 327–332.doi:10.1023/A:1009823425806. . Crossref, ISIGoogle Scholar
    • Xu H, Cai Z.C& Tsuruta H. 2003Soil moisture between rice-growing seasons affects methane emission, production, and oxidation. Soil Sci. Soc. Am. J. 67, 1147–1157. Crossref, ISIGoogle Scholar
    • Yagi K, Tsuruta H& Minami K. 1997Possible options for mitigating methane emission from rice cultivation. Nutr. Cycl. Agroecosyst. 49, 213–220.doi:10.1023/A:1009743909716. . Crossref, ISIGoogle Scholar
    • Yan T, Agnew R.E, Gordon F.J& Porter M.G. 2000Prediction of methane energy output in dairy and beef cattle offered grass silage-based diets. Livest. Prod. Sci. 64, 253–263.doi:10.1016/S0301-6226(99)00145-1. . CrossrefGoogle Scholar
    • Yan X, Ohara T& Akimoto H. 2003Development of region-specific emission factors and estimation of methane emission from rice field in East, Southeast and South Asian countries. Global Change Biol. 9, 237–254.doi:10.1046/j.1365-2486.2003.00564.x. . Crossref, ISIGoogle Scholar