Tuesday, August 7, 2007: 4:00 PM
J1, San Jose McEnery Convention Center
Methane (CH4) emission related to plants is traditionally thought to originate from belowground microbial processes in anaerobic habitats. However, a recent study found aerobic CH4 emission in plants by a hitherto unrecognized process. Our study investigated the difference in CH4 emissions between xerophytes and hydrophytes in the temperate grasslands of Inner Mongolia using laboratory incubation. We found that hydrophytes had plant-mediated CH4 emission while the xerophytes showed plant-derived CH4 emission. This difference may be explained by distinct mechanisms that were responsible for CH4 emission. In the temperate grasslands of Inner Mongolia, dominant steppes species such as Leymus chinensis, Stipa grandis and Agropyron cristatum had no or very weak CH4 emission, while the scarce species such as Achillea frigida, Glyceria spiculosa and Scirpus yagara showed relatively high CH4 emission. Therefore, the steppes in the temperate grasslands might be less important for regional CH4 budget.