摘要:The summer diel variation of methane (CH 4 ) flux was investigated in a eutrophic, subtropical lake in China. The CH 4 concentration was always supersaturated, and the emission rate ranged from 0.24 to 45.51mg m -2 h -1 . The diel variations of CH 4 flux in June and August showed a single peak in early afternoon and a minimum in the morning, while the pattern varied irregularly in May. There was a moderate relationship between water and sediment temperature and CH 4 emission rate in some months.