“…Transport through rice plants, diffusion and ebullition serve as three vehicles for transport of methane from the sites of production in the soil to the atmosphere (Wassmann et al, 1993). Therefore, the entire process of methane emission from rice fields, including production, oxidation and transport to the atmosphere is affected by biotic and abiotic factors, such as growth status of rice, temperature, soil characteristics (Conrad and Rothfuss, 1991;Masscheleyn et al, 1993;Neue, 1993;Sass et al, 1994;Yang et al, 1994;Denier et al, 1996;Hanson and Hanson, 1996;Chang, 1997, 1998;Rath et al, 1999;Kumaraswamy et al, 2000). In addition, under dif- ferent exploitation methods, the amounts of methane emission from wetland ecosystem are also different, usually varying from 0.47 to 171.12 mg m −2 h −1 (Wei, 2000).…”