Reducing Methane Emissions from Rice By
May 5, 2000
Rice production may increase global warming by boosting emission
of an important greenhouse gas: methane. But periodically draining the soil in
rice crops decreases methane emissions drastically,
Agricultural Research Service scientists
have discovered. ARS is the U.S. Department of
Agricultures chief scientific research agency.
Rice is a plant that grows best in wet soil with its roots
flooded. But flooded rice crops emit substantial amounts of methane to the
atmosphere, especially when fresh organic matter, like plant residues,
is added back to the soil, according to soil scientist L. Hartwell Allen.
Hes with ARS Crop Genetic and Environmental Research Unit in
Draining the soil for two or three short periods during the
growing season to aerate the crops roots may be an easy,
environmentally-friendly, on-farm practice that would help decrease methane
Current world rice production is 384 million tons. Rice is the
primary food for about 50 percent of the worlds population.
Methane is a greenhouse-effect gas that has a 20-fold greater
global warming potential than does carbon dioxide (CO2 ). Other studies show
that up to 20 percent of global methane emissions worldwide come from flooded
An article about this research appears in the May issue of
Agricultural Research magazine. The
also on the World Wide Web.
Scientific contact: L.
Hartwell Allen, ARS Crop
Genetics and Environmental Research Unit, Gainesville, Fla.; phone
(352)392-6180, fax (352) 392-6139, firstname.lastname@example.org.