Effect of water table level on CO2, CH4 and N2O emissions in a freshwater marsh of Northeast China

We quantified the effects of the water table on CO2, CH4 and N2O emissions from microcosms in a freshwater marsh in Sanjiang Plain, Northeast China. From July to September in 2005, CO2, CH4 and N2O emission rates were measured in an undisturbed natural marsh (in natural) and microcosms of three manipulated water table treatments: a reference, a high water table (HW) and a low water table (LW). The averages of CO2, CH4 and N2O emissions were 360.2 mg m−2 h−1, 7.43 mg m−2 h−1 and 12.84 μg m−2 h−1, respectively, close to those in reference (p