[Short-term monitoring of methane emission regulation from a municipal solid waste landfill].

To understand the regulation and influencing factors of methane emission from landfills in China, rates of methane emission from Hangzhou Tianziling municipal solid waste landfill were measured by static chamber technique. The emission rates ranged from 3.67 to 36.65 mmol x (m2 x h)(-1) on average of the two tested points (No. 1 and No. 2) during 24-hour cycle. The max ratio of emission rates between the two tested points was 625. The difference with the rates of the two tested points could be explained by the depth of the cover soils. Rate of methane emission from each point correlated with atmospheric pressure and water content of landfill cover soils, and the result from stepwise regression was r2 = 0.89 for point No. 1, r2 = 0.76 for point No. 2. Rates of methane emission varied from -0.23 to 0.32 mmol (m2 x h)(-1) on average in 40-day test (points with same depth of cover soils). The low correlation (r2 = 0.15) with atmospheric pressure showed that atmospheric pressure was not the decisive factor. For some time, emission rates correlated with water content or temperature of the landfill cover soils significantly, but not obvious (r2 < 0.4) during the whole monitoring time. When atmospheric pressure was included, the results of stepwise regression were improved significantly, which showed that methane emission rates were influenced by different factors, but the effect of each factor was not the same at a different time.