Wetlands are a major contributor to the global methane (CH{sub}4) budget. Currently there is a consensus view that drought restrains CH{sub}4 emissions from wetlands. However, a 6-year field experiment investigating the effects of persistentsummer water table drawdown on a gully mire in mid-Wales, U.K. demonstrated a 2-year "boom and bust" cycle of CH{sub}4 emissions followed by a recovery during the third year, when compared with emissions from a control wetland in which the water tableremained at or above the peat surface. This cyclical trend was subsequently replicated by the control wetland following natural summer drought. The experimental wetland was affected less by this natural drought following previous water table drawdown.Depth profiles of CH{sub}4 production suggested that consecutive water table drawdown resulted in a translocation of peak methanogen activity lower down the peat profile, where emissions were affected less by subsequent drawdown. These findings suggestthat wetland CH{sub}4 flux models need to consider the possibility that methane emission-water table relationships are dependent on the pattern and frequency of drought events.
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