Reducing CH4 and CO2 emissions from waterlogged paddy soil with biochar
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A potential means to diminish increasing levels of CO2 in the atmosphere is the use of pyrolysis to convert biomass into biochar, which stabilizes the carbon (C) that is then applied to soil. Before biochar can be used on a large scale, especially in agricultural soils, its effects on the soil system need to be assessed. This is especially important in rice paddy soils that release large amounts of greenhouse gases to the atmosphere.
Materials and methods
In this study, the effects of biochar on CH4 and CO2 emissions from paddy soil with and without rice straw added as an additional C source were investigated. The biochars tested were prepared from bamboo chips or rice straw which yielded bamboo char (BC) and straw char (SC), respectively. BC and SC were applied to paddy soil to achieve low, medium, and high rates, based on C contents of the biochars. The biochar-amended soils were incubated under waterlogged conditions in the laboratory.
Results and discussion
Adding rice straw significantly increased CH4 and CO2 emissions from the paddy soil. However, when soils were amended with biochar, CH4 emissions were reduced. CH4 emissions from the paddy soil amended with BC and SC at high rate were reduced by 51.1% and 91.2%, respectively, compared with those without biochar. Methanogenic activity in the paddy soil decreased with increasing rates of biochar, whereas no differences in denaturing gradient gel electrophoresis patterns were observed. CO2 emission from the waterlogged paddy soil was also reduced in the biochar treatments.
Our results showed that SC was more effective than BC in reducing CH4 and CO2 emissions from paddy soils. The reduction of CH4 emissions from paddy soil with biochar amendment may result from the inhibition of methanogenic activity or a stimulation of methylotrophic activity during the incubation period.
KeywordsBamboo char Greenhouse gas emission Methane Methanogenic activity Paddy field Straw char
- Forster P, Ramaswamy V, Artaxo P et al (2007) Changes in atmospheric constituents and in radiative forcing. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. In: Solomon S, Qin D, Manning M et al (eds) Climate Change 2007: the Physical Science Basis. Cambridge University Press, Cambridge, UK/New York, pp 129–234Google Scholar
- Hanson RS (1998) Ecology of methylotrophic bacteria. In: Burlage RS, Atlas R, Stahl D, Geesey G, Sayler G (eds) Techniques in Microbial Ecology. Oxford University Press, New York, pp 137–162Google Scholar
- Intergovernmental Panel on Climate Change (IPCC) (2007) Agriculture. In: Metz B, Davidson OR, Bosch PR et al (eds) Climate Change 2007: Mitigation, Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panelon Climate Change. Cambridge University Press, Cambridge, UK/New York, pp 498–540Google Scholar
- Knoblauch C, Marifaat AA, Haefele MS (2008) Biochar in rice-based system: Impact on carbon mineralization and trace gas emissions. http://www.biocharinternational.org/2008/conference/posters
- Murray AE, Hollibaugh JT, Orrego C (1996) Phylogenetic compositions of bacterioplankton from two California estuaries compared by denaturing gradient gel electrophoresis of rDNA fragments. Appl Environ Microbiol 62:2676–2680Google Scholar
- Rondon M, Ramirez JA, Lehmann J (2005) Charcoal additions reduce net emissions of greenhouse gases to the atmosphere. In: Proceedings of the 3 rd USDA Symposium on Greenhouse Gases and Carbon Sequestration, Baltimore, USA, March 21–24, p 208Google Scholar
- Rondon MA, Molina D, Hurtado M, Ramirez J, Lehmann J, Major J, Amezquita E (2006) Enhancing the productivity of crops and grasses while reducing greenhouse gas emissions through bio-char amendments to unfertile tropical soils. In: 18th World Congress of Soil Science, July 9–15, Philadelphia, PA, http://crops.confex.com/crops/wc2006/techprogram/P16849.HTM. Accessed June 2008
- Yagi K, Minami K (1990) Effects of organic matter application on methane emission from some Japanese paddy fields. Soil Sci Plant Nutr 36:599–610Google Scholar
- Zwieten VL, Singh B, Joseph S, Kimber S, Cowie A, Chan YK (2009) Biochar and emissions of non-CO2 greenhouse gases from soil. In: Lehmann J, Joseph S (eds) Biochar for Environmental Management Science and Technology. Earthscan Press, UK, pp 227–249Google Scholar