种稻盆钵土壤甲烷排放通量变化的研究

通过温室盆栽试验，研究了不同冬作处理时后茬水稻生长期甲烷排放通量及土壤温度、土壤Ｅｈ的日变化规律。结果表明：连续晴天甲烷排放通量和土壤温度存在明显的昼夜变化，最大值出现在下午４时左右，最小值出现在凌晨４时左右，符合余弦函数变化规律；连续阴雨天甲烷排放通量有逐日降低的趋势，但其昼夜变化缺乏规律性。种稻盆钵土壤甲烷排放通量昼夜变化主要受０～１０ｃｍ深土壤温度的影响，而与土壤氧化还原电位无关。

Study on Diurnal Variations of CH 4 Fluxes from Rice Soils in Pots.

A pot culture experiment of rice in greenhouse was carried out to investigate the diurnal variations of CH 4 fluxes,soil temperatures and soil Eh during rice growing period with different treatments applied in the former winter cropping season.The results showed that there existed obvious diurnal variations of CH 4 fluxes and soil temperatures in continuous fine days.The maximum fluxes occurred at 4 pm while the minimum fluxes at about 4 am,and the variation patterns of CH 4 fluxes and soil temperatures were in conformity with cosine function of time t as a variable.Methane fluxes in continuous overcast and rainy days had a decreasing tendency day by day,and its diurnal variations could not be fitted with a cosine functional curve of time t .Diurnal variations of CH 4 fluxes were mainly influenced by soil temperature at 0 10 cm soil depth.And there is no influence of soil Eh on diurnal variations of CH 4 fluxes.