Methane emission from rice fields as affected by land use change

▶ Conversion of upland crop to rice paddy significantly reduces CH4 emission ▶ Continuous rice cultivation resulted in higher CH4 emission than short-term paddy ▶ High CH4 emissions from continuous rice cultivation was attributed to increase Fe(II) concentration and population of methanogenic archaea ▶ Length of non-paddy significantly reduces electron donor availability as revealed by low Fe(III) reduction and methanogenic archaeal population causing low CH4 emission.