Agriculture and Environment: Rice

Better Management Practices: Reduce Greenhouse Gases

There are several ways to reduce emissions of methane, a greenhouse gas produced in rice paddies.

Research has shown that transplanting 30-day old seedlings, direct seeding on wet soil, and direct seeding on dry soil reduced methane emissions by 5%, 13%, and 37%, respectively, when compared to transplanting 8-day old seedlings.

Ploughing also affects greenhouse gas production. For example, methane emissions following fall ploughing were 26% less than they were following spring ploughing (Ko and Kang 2000).

In addition to reducing rice production's overall contribution to the generation of greenhouse gases, rice fields can sequester some 10 metric tons of carbon per hectare per growing season - but only if crop residue is kept in the soil (Rice Producers of California 2003). If crop residue is burned instead of kept in the soil, the carbon is lost and rice becomes a net contributor to CO2 production.

Burning rice husks at processing plants is not only harmful environmentally, it is a waste of resources. Rice husks have tremendous value in many greenhouse operations and are in fact bought and transported great distances as a valuable raw material for soil amendments.