We examined diel, seasonal and inter-annual variations of CH4
efflux and environmental factors. Although CH4
efflux showed no apparent diel pattern, summer CH4
efflux was significantly higher than those of other three seasons. CH4
effluxes were highly timescale dependent on wind, substrate availability, and sediment temperature. The timescale dependence of environmental controls on CH4
effluxes has important implications in modeling CH4
emissions in lakes.