Read: article about the research in Agricultural Research

Reducing Methane Emissions from Rice

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 Agriculture’s 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. He’s with ARS’ Crop Genetic and Environmental Research Unit in Gainesville, Fla.

Draining the soil for two or three short periods during the growing season to aerate the crop’s roots may be an easy, environmentally-friendly, on-farm practice that would help decrease methane emissions.

Current world rice production is 384 million tons. Rice is the primary food for about 50 percent of the world’s 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 rice fields.

An article about this research appears in the May issue of Agricultural Research magazine. The story is 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, lhallen@gainesville.usda.ufl.edu.