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Field potential

Mitigation practice

Estimated decrease

(Tg CH4.m-2.h-1)

Water management

5.0 (3.3-9.9)

~30%

Nutrient management

10.0(2.5-15.0)

~20%

Cultural practices

5.0(2.5-10.0)

~20%

inated by N2 with smaller quantities of CH4 (Sharpe et al. 2002). A portion of CH4 emitted to the atmosphere can be sequestered by aerobic soils. Thus, land application of manure could significantly decrease the net quantity of CH4 emitted to the atmosphere compared to stockpiling or long-term storage of manure. Manure applied to pasture land did not appear to impact CH4 emission (Chad-wick et al. 2000). On the other hand, net uptake of CH4 under corn from mold-board plowed soils amended with manure was reduced relative to soils without manure.

c. Animal management: Livestock sources of CH4 are predominantly enteric (i.e. from the breath of ruminants and flatus of monogastric animals) as a result of feed digestion. Globally, enteric production of CH4 was estimated at ~80Tg.yr-1, which was 20-25% of the observed increase in atmospheric CH4 concentration (Lassey 2007). Methane emission can be reduced by feeding more concentrates, normally replacing fodder (Beauchemin and McGinn 2005). Although concentrates might increase daily CH4 emission, emissions per kg feed intake and per kg product are reduced due to better efficiency. Other practices that can reduce CH4 emissions include: (a) adding oils to the diet, (b) improving pasture quality and (c) optimizing protein intake. While dietary supplements in the form of ionophores, halogenated compounds, propionate precursors have been tested, their efficacy is doubtful and their overall environmental impact is also under cloud.

d. Consumption of CH4 by soil: Soils have the potential to consume CH4 by the activities of methanotrophic bacteria which constitute the only known net biological sink for atmospheric CH4 and terrestrial emissions. Methanotrophic bacteria are able to oxidize CH4 for energy purposes or for building up of microbial biomass (Hanson and Hanson 1996). Methane uptake is controlled by the interplay of biotic and abiotic factors providing proximate limitation on CH4 oxidation. Methane oxidation in the rice fields is assumed to consume about one-third of the CH4 production (Bosse and Frenzel 1997), although values as high as 90% have also been reported (Schutz et al. 1989). There is an evidence that agricultural practices have adverse effects on the CH4-oxidizing ability of soils (Arif et al. 1996; Kessavalou et al. 1998; Hutsch 2001). Cultivation appears to decrease net CH4 consumption, as CH4 oxidation potentials of cultivated soils are less than in grasslands (Mosier et al. 1996; Kessavalou et al. 1998). Nitrogen fertilization has also been identified among other factors as an important contributor to this effect. In many cases, NH4 is the most detrimental form of N for CH4 oxidation (Bronson and Mosier 1994). In a long-term fertilization experiment, CH4 consumption was significantly lowered after application of mineral N. On the contrary, stimulation of CH4 oxidation by NH4-based fertilizers in soil and around rice roots has also been reported - both in microcosm (Bodelier et al. 2000) and under field conditions (Kruger and Frenzel 2003). It was suggested that elevated CH4/NH4+ ratio in the rooted soil greatly reduces the inhibitory effect of NH4+ (Cai and Mosier 2000). Methane oxidation in an alluvial soil planted to rice under a long-term fertilization experiment was stimulated following the application of mineral fertilizers or compost, indicating nutrient limitation as one of the factors affecting the process (Nayak et al. 2007). Combined application of compost and mineral fertilizer, however, inhibited CH4 oxidation probably due to N immobilization by the added compost.

15.4.3 Nitrous Oxide

Nitrous oxide is emitted from agricultural soils by soil microbial processes of nitrification (aerobic transformation of ammonium to nitrate) and denitrification (anaerobic transformation of nitrate to N2 gas (Sahrawat and Keeney 1986; Monteny et al. 2006). The main cause of increases in agricultural N2O emission to the atmosphere is the application of N fertilizers and animal manure management. The major factors controlling soil nitrification-denitrification are soil pH, texture, organic C supply, crop residue management, temperature, soil N content, soil aeration and water status and certain agri-chemicals (Sahrawat and Keeney 1986).

a. Animal manure management: Animal manures can release significant amount of N2O during storage, but their magnitude varies. Preliminary evidences suggest that covering manure heaps can reduce N2O emissions (Chadwick 2005). For most animals worldwide, especially the grazing ones, there is limited scope for manure management, as excretion happens in the field. However, emissions from manure may be curtailed to a limited extent by altering the feeding practices (Kulling et al. 2003), but these mechanisms and the system-wise influence have not been widely explored.

Rotz (2004) outlined several management options to reduce N loss from animal manure management. Management should focus on improving N-use efficiency of animals to reduce N excretion, retaining N contained in manure until it is applied to land and applying the appropriate amount of manure in a timely manner to enhance crop uptake. Nitrous oxide emission from livestock faeces deposited on pasture is dependent on rainfall, quantity and frequency of N-inputs from stocking rate and soil organic C level (Saggar et al. 2007).

b. N2 O emission management from agricultural fields: In general, N2O emission increases with increased N-inputs (Gregorich et al. 2005). The proportion of applied N emitted as N2O has been estimated at 1.25% (IPCC 1997). Both fertilized and unfertilized soils emit N2O. While fertilizer-N is a source of N2O in case of fertilized soils, mineralization of soil organic-N contributes to the production of N2O from unfertilized soils (Aulakh et al. 2000b). The scope of different management practices mitigating N2O emission from croplands and their field potential is listed in Table 15.5. McSwiney and Robertson (2005) reported that N2O fluxes were low to moderate until the N-input exceeded crop needs, after which the flux nearly doubles, suggesting that prudent management of N-inputs can be an effective strategy to minimize N2O emitted from croplands. Emission of N2O after application of anhydrous ammonia was 2-4 times higher than surface applying urea, ammonium nitrate or broadcasting urea (Venterea et al. 2005).

Table 15.5 List of practices to improve fertilizer and manure N-use efficiency in agriculture and expected reduction of N2O emissions assuming global application of mitigation practices (Mosier et al. 1998)_

Estimated decrease in N2O emissions Field

Practice followed (Tg.yr-1) potential

1. Match N supply with crop demand 0.24 ~50%

• Use soil/plant testing to determine fertilizer N needs

• Minimize fallow period to limit mineral N accumulation

• Optimize split application schemes

• Match N application to reduce production goals in region of crop over-production

• Integrate animal and crop production systems in terms of manure reuse in plant production

• Maintain plant residue N on the production site

3. Use advanced fertilization techniques 0.15 ~50%

• Controlled release fertilizers

• Place fertilizers below the soil surface

• Foliar application of fertilizers

• Use nitrification inhibitors

• Match fertilizer type to seasonal precipitation

4. Optimize tillage, irrigation and drainage 0.15 ~40%

Fertilizing with ammonium fertilizers, like urea, increased the potential for ammonia emission (Harrison and Webb 2001), but under anaerobic flooded soil, it could minimize gaseous N emissions via denitrification (Aulakh 1989). N2O emission from field crops is strongly related to the moisture status of the soil. Drying conditions affect nitrification favour low N2O production, but when aerobic periods are followed by irrigation/flooding, large N2O fluxes are observed. The N2O emissions often increase with increasing aeration (decreasing water-filled pore space) during drainage of anaerobic rice soils. Cai et al. (1997) found a very small N2O flux when the rice paddy plots were flooded, but it peaked at the beginning of the disappearance of floodwater, suggesting a trade-off between CH4 and N2O emissions. Substantial N2O emission can occur during freeze-thaw events (Gregorich et al. 2005). Even though the soil temperatures may be near 0°C, the emission of N2O is due to microbial activity (Chang and Hao 2001) and the production of N2O exceeds its reduction to gaseous N2 at low temperature, thus contributing to N2O emission during spring-thaw events (Holtan-Hartwig et al. 2002).

15.5 Trade-Offs and GWP

Assessing the impact of agriculture on global climate change requires converting emission data to GWP. Cole et al. (1997) estimated that agriculture has the potential to reduce radiative forcing from 1.2 to 3.3PgCO2-Ceq. yr-1. It was estimated that about 32% could be from reduced CO2 emissions, 42% from C offsets through biofuel production on 15% of the existing croplands, 16% from reduced CH4 emissions and 10% from reduced emission of N2O.

A full-cost accounting of the effects of agriculture on greenhouse gas emissions is necessary to quantify the relative importance of all mitigation options. Such an analysis shows nitrogen fertilizer, agricultural liming, fuel use, N2O emissions and CH4 fluxes to have additional significant potential for mitigation (Robertson and Grace 2004). Net GWP calculations should take into consideration the sum of net GHG emission after deducting the biological consumption and chemical decay, biomass production and ideally net changes in soil organic carbon (SOC). Lal (2007) estimated that SOC sequestration potentially could offset ~15% of the global CO2 emission. There are potential trade-offs between SOC sequestration and GHG emission, as conservation tillage enhanced N2O emission. Mosier et al. (2005) reported that SOC storage relative to total emission determined whether a site would provide a net increase or decease in GWP. Their comparisons included GWP from farm operations (planting, harvesting and applying pesticides), fertilizer, liming, irrigation, N2O, CH4 and change in surface SOC (0-5 or 0-7.5 cm).

Calculating net GWP appears simple, sum the GHG emission from all sources (soil, energy use etc.) and deduct the sum of total GHG consumption (C sequestration, methane consumption etc.). However, such measurements are fraught with high spatial and temporal variability. Mosier et al. (2006) compared two methods of estimating net GWP, one based on SOC change (0-7.5 cm) and the other based on soil respiration. The two calculation methods resulted in highly different estimates of GWP, both qualitative and quantitative. It is thus important that while reporting GWP, assumptions and calculations are carefully and clearly delineated.

15.5.1 Policy Issues on Agricultural GHG Mitigation

Recent study has shown that there is a significant economic potential for GHG mitigation in agriculture, with total potentials of 1900-2100, 2400-2600 and 3100-3300Mt CO2 yr-1 at carbon prices of 0-20, 0-50 and 0-100 US $ per ton CO2-eq., respectively (Smith et al. 2007). About 70% of this potential arises from developing countries with a further 10% from countries with economies in transition (Trines et al. 2006). Despite such significant economic potential, there are several barriers that could prevent the implementation of these measures. Many of these barriers are particularly prevalent in developing countries and include economic, risk-related, political, logistical and education as well as societal barriers.

a. Economic barriers include the cost of land, competition for land, continued economic penury, lack of existing capacity, low price of carbon, population growth, transaction costs and monitoring costs.

b. Risk related barriers include the delay on returns from investment, issues of stability (particularly of C sinks) and issues related to leakage and natural variation in C sink strength.

c. Political barriers include unclear policies on land use planning and the lack of clarity in carbon/GHG accounting rules and overall a lack of political will.

d. Logisitical barriers include scattered nature of land holdings and conflict of interest among landowners, accessibility to large areas and biological suitability of the land areas for GHG farming.

e. The educational and societal barriers include newer legislations governing the sector, stakeholders' perception and the persistence of traditional practices.

Maximizing the productivity of existing agricultural land and applying best management practices would help to reduce greenhouse gas emissions (Smith et al. 2008). Ideally, agricultural mitigation measures need to be considered within a broader framework of sustainable development. Policies to encourage sustainable development will make agricultural mitigation in developing countries more achievable. The barriers to implementation of mitigation actions in developing countries need to be overcome, if we are to realize even a proportion of the 70% of global agricultural climate mitigation potential that is available in these countries.

15.6 Research Needs

Although GHG emission derived from soil has been researched for several decades, there are still geographic regions and agricultural systems that have not been well characterized. There is an urgent need to estimate GWP across a wide range of agricultural systems. Ideally, a standard or benchmark method to calculate GWP should be established. Methodology to improve the accuracy of determining changes in SOC and GHG emissions would reduce the uncertainty of estimating GWP. Similarly, farmers' participation appears indispensable for technology transfer of any kind, including management changes aimed at sustainable production systems. It is essential to initiate dialogue with the farmers and other stakeholders about GHG concerns and the agricultural practices that would help in mitigating the menace, through various routes:

(i) Improving the understanding of farmers' perceptions and decision making to classify different target groups for specific mitigation strategies.

(ii) Conducting research on farmers' fields or community areas (instead of research stations) as a 'reality check' for suggested improvements.

(iii) Developing alternative management options in close collaboration with farmers preferably derived from indigenous knowledge on sustainable management practices.

(iv) Focusing on farm households rather than individual production systems and evaluating the economic benefit to the farmer, e.g. affordability versus profitability.

(v) Packaging scientific knowledge in practical and user-friendly forms through easy decision-support tools.

(vi) Establishing continuous feed-back on mitigation strategies over longer time spans, e.g. farmers' perception on water pricing may vary according to weather events.

(vii) Educating farmers and rural communities by knowledge initiatives. 15.7 Conclusion

There are significant opportunities for mitigation of GHG in agriculture, however, there are large uncertainties and it is difficult to assess the effectiveness of GHG mitigation measures under the changing environmental conditions. Many recent studies have shown that actual levels of GHG mitigation are far below the technological potential for these measures. However, several barriers, mostly economical, and lack of political will, act as deterrent to achieve this technological potential. The estimated biophysical potential of approximately 5500-6000 Mt CO2 yr-1 would not be realized due to these constraints. With appropriate policies - education and policy initiatives, it may be possible for agriculture to make a significant contribution to climate mitigation by 2030.

Many agricultural mitigation options have both co-benefits (in terms of improved efficiency, reduced cost and environmental benefits) and trade-offs. Many agricultural GHG mitigation options could be implemented immediately without any further technological development, while a few options are still undergoing technological validation. It is important that policy planners understand the issue of climate change vis-a-vis GHG mitigation measures or potential opportunities and get motivated to act and analyze the costs and benefits of mitigation actions. The long-term outlook for GHG mitigation in agriculture suggests that there is a significant potential, but many uncertainties, both price and non-price related, will determine the level of implementation.

References

Adhya TK, Patnaik P, Satpathy SN, Kumaraswamy S, Sethunathan N (1998) Influence of phosphorus application on methane emission and production in flooded paddy soils. Soil Biol Biochem 30:177-181

Adhya TK, Rath AK, Gupta PK, Rao VR, Das SN, Parida KM, Parashar DC, Sethunathan N (1994) Methane emission from flooded rice fields under irrigated conditions. Biol Fertil Soils 18:245-248

Arif SMA, Houwen F, Verstrate W (1996) Agricultural factors affecting methane oxidation in arable soil. Biol Fertil Soils 21:95-102 Aulakh MS (1989) Transformations of ammonium nitrogen in upland and flooded soils amended with crop residues. J Indian Soc Soil Sci 37:248-255 Aulakh MS, Khera TS, Doran JW (2000a) Mineralization and denitrification in upland, nearly saturated and flooded subtropical soil. I. Effect of nitrate and ammoniacal nitrogen. Biol Fertil Soils 31:162-167

Aulakh MS, Wassmann R, Rennenberg H (2000b) Methane emissions from rice fields - quantification, role of management and mitigation options. Adv Agron 70:193-260 Babu YJ, Nayak DR, Adhya TK (2006) Potassium application reduces methane emission from a flooded field planted to rice. Biol Fertil Soils 42:532-541 Beauchemin KA, McGinn SM (2005) Methane emission from feedlot cattle fed barley on corn diets. J Animal Sci 83:653-661 Bharati K, Mohanty SR, Singh DP, Rao VR, Adhya TK (2000) Influence of incorporation or dual cropping of Azolla on methane emission from a flooded alluvial soil planted to rice in Eastern India. Agric Ecosyst Environ 79:73-83 Bodelier PLE, Roslev P, Henckel T, Frenzel P (2000) Stimulation by ammonium-based fertilisers of methane oxidation in soil around rice roots. Nature 403:421-424 Bosse U, Frenzel JP (1997) Activity and distribution of CH4 oxidizing bacteria in flooded rice microcosms and in rice plants (Oryza sativa). Appl Environ Microbiol 63:1199-1207 Bronson KF, Mosier AR (1994) Suppression of methane oxidation in aerobic soil by nitrogen fertilizers, nitrification inhibitors and urease inhibitors. Biol Fertil Soils 17:263-268 Cai Z, Mosier AR (2000) Effect of NH4Cl addition on methane oxidation by paddy soils. Soil Biol Biochem 32:1537-1545

Cai Z, Xing G, Yan X, Xu H, Tsuruta H, Yagi K, Minami K (1997) Methane and nitrous oxide emissions from rice paddy fields affected by nitrogen fertilizers and water management. Plant Soil 196:7-14

Chadwick DR, Pain BF, Brookeman SKE (2000) Nitrous oxide and methane emissions following application of animal manure to grassland. J Environ Qual 16:443-447 Chadwick DR (2005) Emissions of ammonia, nitrous oxide and methane from cattle manure heaps:

effect of compaction and covering. Atmos Environ 39:787-799 Chang C, Hao X (2001) Source of N2O emission from a soil during freezing and thawing. Phyton.

Annals Rei Botanicae 41:49-60 Cole CV, Duxbury J, Freney J, Heinemeyer O, Minami K, Mosier A, Paustian K, Rosenberg N, Simpson N, Sauerbeck D, Zhao Q (1997) Global estimates of potential mitigation of greenhouse gas emissions by agriculture. Nutr Cycl Agroecosys 49:221-228 FAO [Food and Agriculture Organization] (2003) World agriculture: towards 2015/2030. An FAO perspective, FAO, Rome

Gregorich EG, Rochette P, VandenBygaart AJ, Angers DA (2005) Greenhouse gas contributions of agricultural soils and potential mitigation practices in Eastern Canada. Soil Tillage Res 83:5372

Hanson RS, Hanson TE (1996) Methanogenic bacteria. Microbiol Rev 60:439-471 Harrison R, Webb J (2001) A review of the effect of N fertilizer type on gaseous emission. Adv Agron 73:65-108

Holtan-Hartwig L, Dorsch P, Bakken LR (2002) Low temperature control of soil denitrifying communities: kinetics of N2O production and reduction. Soil Biol Biochem 34:1797-1806 Huggins DR, Allmaras RR, Clapp CE, Lamb JA, Randall GW (2007) Corn-soybean sequence and tillage effects on soil carbon dynamics and storage. Soil Sci Soc Am J 71:145-154 Hutsch BW (2001) Methane oxidation in non-flooded soils as affected by crop production. European J Agron 14:237-260 IPCC [Intergovernmental Panel on Climate Change] (1997) Guidelines for national greenhouse gas inventories. In: Intergovernmental Panel on Climate Change/Organization for Economic Cooperation and Development, OECD, Paris

IPCC [Intergovernmental Panel on Climate Change] (2007) Intergovernmental Panel on Climate Change, WGI, Fourth Assessment Report, Climate Change, 2007: The Physical Science Basis, Summary for Policymakers. http://www.ipcc.ch/SPM2feb07.pdf Kessavalou A, Mosier AR, Doran JW, Drijber RA, Lyon DJ, Heinemeyer O (1998) Fluxes of carbon dioxide, nitrous oxide, and methane in grass sod and winter wheat-fallow tillage management. J Environ Qual 27:1094-1104 Kruger M, Frenzel P (2003) Effects of N-fertilization on CH4 oxidation and production, and consequences for CH4 emissions from microcosms and rice fields. Global Change Biol 9:773-784 Kruger M, Frenzel P, Conrad R (2001) Microbial processes influencing methane emission from rice fields. Global Change Biol 7:49-63 Kulling DR, Menzi H, Sutter F, Lischer P, Kreuzer M (2003) Ammonia, nitorus oxide and methane emissions from differently stored dairy manure derived from grass- and hay-based rations. Nutr Cycl Agroecosys 65:13-22 Lal R (2004) Soil carbon sequestration impacts on global climate change and food security. Science 304:1623-1627

Lal R (2007) Carbon management in agricultural soils. Mitigation and adaptation strategies for global change. Global Change 12:303-322 Lassey KR (2007) Livestock methane emissions: from the individual grazing animal through national inventories to the global methane cycle. Agric Forest Meteorol 142:120-132 Mandal B, Majumder B, Adhya TK, Bandyopadhyay PK, Gangopadhyay A, Sarkar D, Kundu MC, Gupta Choudhury S, Hazra GC, Kindu S, Samantaray RN, Misra AK (2008) Potential of double-cropped rice ecology to conserve organic carbon under subtropical climate. Global Change Biol 14:2139-2151 McSwiney CP, Robertson GP (2005) Nonlinear response of N2O flux to incremental fertilizer addition in a continuous maize (Zea mays L.) cropping system. Global Change Biol 11:17121719

Millenium Ecosystem Assessment (2005) Findings from the conditions and trend working group.

Washington, DC, Island Press Mishra S, Rath AK, Adhya TK, Rao VR, Sethunathan N (1997) Effect of continuous and alternate water regimes on methane efflux from rice under greenhouse conditions. Biol Fertil Soils 24:399-405

Mitra S, Jain MC, Kumar S, Bandyopadhya SK, Kalra N (1999) Effect of rice cultivars on methane emission. Agric Ecosyst Environ 73:177-183 Monteny GJ, Bannink A, Chadwick D (2006) Greenhouse gas abatement strategies for animal husbandry. Agric Ecosyst Environ 112:163-170 Mosier AR, Duxbury M, Freney JR, Heinemeyer O, Minami K (1998) Nitrous oxide emissions from agricultural fields: Assessment, measurement and mitigation. Plant Soil 181:95-108 Mosier AR, Halvorson AD, Peterson GA, Robertson GP, Sherrod L (2005) Measurement of net global warming potential in three agroecosystems. Nutr Cycl Agroecosys 72:67-76 Mosier AR, Halvorson AD, Reule CA, Liu XJ (2006) Net global warming potential and greenhouse gas intensity in irrigated cropping systems in Northeastern Colorado. J Environ Qual 35:15841598

Mosier AR, Patron WJ, Valentine DW, Ojima DS, Schimel DS, Delgado JA (1996) CH4 and N2O fluxes in the Colorado shortgrass steppe. Part I: Impact of landscape and nitrogen addition. Global Biogeochem Cycles 10:387-399 Mutuo PK, Cadisch G, Albrecht A, Palm CA, Verchot L (2005) Potential of agroforestry for carbon sequestration and mitigation of greenhouse gas emissions from soils in the tropics. Nutr Cycl Agroecosyst 71:43-54

Nayak DR, Babu YJ, Datta A, Adhya TK (2007) Methane oxidation in an intensively cropped tropical rice field soil under long-term application of organic and mineral fertilizers. J Environ Qual 36: 1577-1584

Neue H-U, Roger PA (1993) Rice agriculture: factor controlling emissions. In: Khalil MAK (ed) The Global Cycle of Methane: Sources, Sinks, Distribution and Role in Global Change. NATO Advance Science Series, Springer-Verlag, Berlin, pp 254-298

Ogle SM, Breidt FJ, Paustian K (2005) Agricultural management impacts on soil organic carbon storage under moist and dry conditions of temperate and tropical regions. Biogeochem 72:87121

Paustian K, Babcock BA, Hatfield J, Lal R, McCarl BA, McLaughlin S, Mosier A, Rice C, Robertson GP, Rosenberg NJ, Rosenzweig C, Schlesinger WH, Ziberman D (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, pp 120 Rath AK, Swain B, Ramakrishnan B, Panda D, Adhya TK, Rao VR, Sethunathan N (1999) Influence of fertilizer management and water regime on methane emission from rice fields. Agric Ecosyst Environ 76:99-107 Reicosky DC, Archer DW (2007) Moldboard plow tillage depth and short-term carbon dioxide release. Soil Tillage Res 94:109-121 Reicosky DC, Hatfield JL, Sass RL (2000) Agricultural contribution to greenhouse gas emissions. In: Reddy R, Hodges H (eds) Climate Change and Global Crop Productivity, CABI Publishing, Wallingford, Oxon, UK, pp 37-55 Richter B (2004) Using ethanol as an energy source. Science 305:340

Robertson GP, Grace PR (2004) Greenhouse gas fluxes in tropical and temperature agriculture: the need for a full-cost accounting of global warming potential. Environ Develop Sustain 6:51-63. Rotz CA (2004) Management to reduce nitrogen losses in animal production. J Animal Sci 82:E119-E137

Saggar S, Giltrap DL, Li C, Tate KR (2007) Modelling nitrous oxide emissions from grazed grasslands in New Zealand. Agric Ecosyst Environ 119:205-216 Sahrawat KL, Keeney DR (1986) Nitrous oxide emissions from soil. Adv Soil Sci 4:103-110 Satpathy SN, Mishra S, Adhya TK, Ramakrishnan B, Rao VR, Sethunathan N (1998) Cultivar variation in methane efflux from tropical rice. Plant Soil 202:223-229 Schutz H, Holzapfel-Pschorn A, Conrad R, Rennenberg H, Seiler W (1989) A 3-year continuous record on the influence of day-time, season and fertilizer treatment on methane emission rates from an Italian rice paddy. J Geophys Res 94:16405-16416 Shalini S, Kumar S, Jain MC (1997) Methane emission from two Indian soils planted with different rice cultivars. Biol Fertil Soils 25:285-289 Sharpe RR, Harper LA, Byers FM (2002) Methane emissions from swine lagoons in southeastern

US. Agric Ecosyst Environ 90:17-24 Smith P, Martino D, Cai Z, Gwary D, Janzen H, Kumar P, McCarl B, Ogle S, O'Mara F, Rice C, Scholes B, Sirotenko O, Howden M, McAllister T, Pan G, Romanenkov V, Schneider U, Towprayoon S (2007) Policy and technological constraints to implementation of greenhouse gas mitigation options in agriculture. Agric Ecosyst Environ 118:6-28 Smith P, Martino D, Cai Z, Gwary D, Janzen H, Kumar P, McCarl B, Ogle S, O'Mara F, Rice C, Scholes B, Sirotenko O, Howden M, McAllister T, Pan G, Romanenkov V, Schneider U, Towprayoon S, Wattenbach M, Smith J (2008) Greenhouse gas mitigation in agriculture. Phi! Trans Royal Soc B 363:789-813 Spatari S, Zhang Y, Maclean HL (2005) Life cycle assessment of switchgrass- and corn stover-

derived ethanol fueled automobiles. Environ Sci Technol 39:9750-9758 Trines E, Hohne N, Jung M, Skutsch M, Petsonk A, Silva-Chavez G, Smith P, Nabuurs GJ, Verweij P, Schlamadinger B (2006) Integrating agriculture, forestry ad other land use in future climate regimes: Methodological issues and policy options. A Report for the Netherlands Research Programme on Climate Change (NRP-CC), pp 188 US-EPA [US-Environmental Protection Agency] (2006) Global Mitigation of Non-CO2 Greenhouse gases (US-EPA Report 430-R-06-005). United States Environmental Protection Agency, Office of the Atmospheric Programs (6207J), Washington, DC. http://www.epa.gov/nonco2/econo-inv/international.html US-EPA [US-Environmental Protection Agency] (2007) 2007 Draft U.S. Greenhouse Gas Inventory Report: DRAFT Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2005. United States Environmental Protection Agency, Office of Atmospheric Programs (6207J), Washington, DC. http://epa.gov/climatechange/emissions/usinventoryreport07.html

Venterea RT, Burger M, Spokas KA (2005) Nitrogen oxide and methane emissions under varying tillage and fertilizer management. J Environ Qual 34:1467-1477 Wassmann R, Neue H-U, Ladha JK, Aulakh MS (2004) Mitigating greenhouse gas emission from rice-wheat cropping systems in Asia. In: Eassmann R, Vlek PLG (eds) Tropical Agriculture in Transition - Opportunities for Mitigating Greenhouse Gas Emissions. Kluwer Academic Publications, Dordrecht, The Netherlands, pp 65-90 Wassmann R, Papen H, Rennenberg H (1993) Methane emission from rice paddies and possible mitigation strategies. Chemosphere 26:201-217

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