Methane emission from terrestrial herbaceous plant

Methane(CH₄) is an important greenhouse gas and its atmospheric concentration has almost tripled since pre-industrial times. It plays a central role in atmospheric oxidation chemistry and affects stratospheric ozone and water vapour levels. Most of the methane from natural sources in Earth's atmosphere was thought to originate from soil microbial processes in anoxic environments. However, in recent years, some studies have demonstrated that the plant may play an important role in CH₄ emissions. Up to now, the research on CH₄ emissions from plant is still at early stage both at home and abroad. Here we firstly using gas chromatography investigated methane emissions under aerobic conditions from aboveground tissues of 12 species terrestrial herbaceous plant in Northeast China. The results showed that all species measured can emit CH₄. Three of which Lolium perenne, Artemisia apiacea and Spinacia oleracea Linn exhibited the highly methane emissions which were 15.14, 12.95 and 8.5 ngCH₄ g^-1 dry weight h^-1, respectively. Cutting stimulated CH₄ emission from fresh branches and leaves, the flux increasing 3-26%.The results suggest terrestrial herbaceous plant itself can emit CH₄ and cutting stimulate CH₄ emission by plant.