With the increase of environmental temperature,the rate of methane emission is increased in ricefields.It is increased gradually with the processing of plant growing in the early rice.Most of methane is emitted with high rates during the early stage of plant growth in the late rice.The diel methane emission showed a regular pattern,with the valley at 6:00~8:00 and the peak at 14:00.This rate is closely related to both the soil temperature and the content of the water\|soluble methane at 5cm depth.The applic...