Effect of plant and light on CH₄ exchange in the soil-plant system of wheat fields

Methane (CH₄) fluxes in wheat fields of the North China Plain were measured by closed chamber and GC techniques. The measured fluxes in the soil-plant systems through opaque chamber and transparent chamber were then compared. The results show obvious seasonal variations but insignificant diurnal variations in CH₄ flux in the system. Wheat cover induces larger seasonal flux variation in the soil-plant system. Wheat and light increase soil-plant CH₄ uptake. More importantly, however, transparent closed chamber proves the best CH₄ flux measurement method in the field experiment.