Improved Rice Cultivation
Rice is the staple food of 3 billion people, providing one-fifth of calories consumed worldwide. Its cultivation is responsible for at least 10 percent of agricultural greenhouse gas emissions and 9 to 19 percent of global methane emissions. That is because flooded rice paddies are ideal anaerobic environments for methane-producing microbes that feed on decomposing organic matter, a process known as methanogenesis.
There are four general techniques, best used in combination, to improve rice production and reduce emissions:
- Water: Mid-season drainage and alternate wetting and drying improve aerobic conditions.
- Nutrients: More balanced application of nutrients reduces methane emissions while supporting yields.
- Plant varieties: Rice varieties (cultivars) that are less water-loving can be used in more aerobic environments.
- Tillage: Techniques for seeding rice without tilling the ground maintain stable soils.
These techniques can make rice production efficient, dependable, and sustainable, helping to meet growing demand for this staple food without causing warming. Mid-season drainage alone reduces methane emissions by 35 to 70 percent. Given that many rice farming methods are long-entrenched customs, change requires helping farmers see what results are possible, cultivating necessary knowledge and skills, and implementing incentives that make new methods compelling.
“their breed has fed our folk”: Van Tri, Phan. “Grains of Rice.” In An Anthology of Vietnamese Poems., edited and translated by Huynh Sanh Thong. London: Yale University Press, 1996.
one-fifth of calories consumed: Elert, E. “Rice by the Numbers: A Good Grain.” Nature, 514, no. 7524 (2014): S50-S51.
rice cultivation…emissions: Adhya, T. K., et al. “Wetting and Drying: Reducing Greenhouse Gas Emissions and Saving Water from Rice Production.” Working Paper, Installment 8 of Creating a Sustainable Food Future. Washington, D.C.: World Resources Institute, 2014; Forster, P., et al. “Changes in Atmospheric Constituents and in Radiative Forcing.” In Climate Change 2007: Thee Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, UK, and New York: Cambridge University Press, 2007.
[more] methane…as the planet gets hotter: Ziska, L. H., P. R. Epstein, and W. H. Schlesinger. “Rising CO2, Climate Change, and Public Health: Exploring the Links to Plant Biology.” Environmental Health Perspectives 117, no. 2 (2009): 155–158.
Methane [vs.] carbon dioxide: Myhre, Gunnar, Drew Shindell, François-Marie Bréon, William Collins, Jan Fuglestvedt, Jianping Huang, Dorothy Koch et al. “Anthropogenic and natural radiative forcing.” In Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, UK, and New York: Cambridge University Press, 2013.
“discovered almost by accident”: de Laulanié, Henri. “Technical Presentation of the System of Rice Intensification, Based on Katayama’s Tillering Model.” Madagascar: Association Tefy Saina, 1992. http://sri.ciifad.cornell.edu/aboutsri/Laulanie.pdf.
“a less-is-more ethic”: Broad, William J. “Food Revolution That Starts with Rice.” New York Times. June 17, 2008.
[SRI] practiced by 4 million to 5 million farmers: Vidal, John. “India’s Rice Revolution.” The Guardian. February 16, 2013.
Sumant Kumar…world-record yield: Diwakar, M.C., Arvind Kumar, Anil Verma, and Norman Uphoff. “Report on the World Record SRI Yields in Kharif Season 2011 in Nalanda District, Bihar State, India.” Agriculture Today. June 2012.
[benefits of] transplanting single seedlings: Bhatt, K.N. “System of Rice Intensification for Increased Productivity and Ecological Security: A Report.” Rice Research: Open Access 3 (2015): 147.
mid-season drainage…reduces methane: Adhya et al, “Wetting and Drying”; Yu, K., G. Chen, and W.H. Patrick. “Reduction of Global Warming Potential Contribution from a Rice Field by Irrigation, Organic Matter, and Fertilizer Management.” Global Biogeochemical Cycles 18, no. 3 (2004): GB3018.
yields…seed use…water inputs: Latham, Jonathan. “How Millions of Farmers Are Advancing Agriculture for Themselves.” Independent Science News. December 3, 2012; Surridge, Christopher. “Rice Cultivation: Feast or Famine?” Nature 428 (2004): 360-361.
“not intrinsically labor-intensive”: Charles, Dan. “Unraveling the Mystery of a Rice Revolution.” National Public Radio. May 3, 2013.
Farm incomes can double: Namara, Regassa E., Parakrama Weligamage, and Randolph Barker. “Prospects for Adopting System of Rice Intensification in Sri Lanka.” Research Report 75. Colombo, Sri Lanka: International Water Management Institute, 2004.
spread to some forty countries: Bhatt, “System.”