Estimates of global methane production from rice paddies based on substrate requirement

Abstract

Estimates of methane emission from rice paddies are highly variable and hence detectable. Most of the estimates were made without consideration of the substrate requirements. A mole of glucose should normally produce 2 moles of methane yielding 178 mg methane from 1 g of glucose. In our incubation experiment only 10-11% of this potential efficiency was realized. Estimates of biomass of globally produced rice were made from the yield of rice and thus of the potential leaching of the organic substances which gives an upper limit of 13 Tg global methane production from rice paddies.