Agriculture and Environment: Rice

Environmental Impacts of Production: Production of Greenhouse Gases

There is much speculation about the impact of climate change on the ability of agriculture to feed more people.

However, agriculture itself can have a significant effect on global warming through the release of greenhouse gases. Continuously flooded rice fields, in particular, release methane to the atmosphere (Wassmann et al. 2000).

One estimate places methane emissions from rice at some 10-15% of total global methane emissions (Neue 1993, as cited in Wang et al. 2000). Other estimates suggest that the contribution of rice paddies to global rates of methane emission ranges from 5-30% (Minami and Neue 1993, as cited in Witte et al. 1993). If there is an increase in yields or areas harvested, methane emissions would increase as well.

The processing of rice in large dehuskers leads to the accumulation of large amounts of rice husk waste. This waste is normally burned to reduce the volume and therefore the disposal problem. The burning of waste releases both carbon dioxide and carbon monoxide into the environment.