下辽河平原典型农田融化期氧化亚氮和甲烷排放通量研究

Nitrous oxide and methane emissions from different agricultural fields during freezing and thawing periods in the lower reaches of Liaohe Plain.

应用静态箱/气相色谱法对下辽河平原典型农田(大豆地、玉米地、水稻田)土壤融化期N2O和CH4排放通量进行了研究。结果表明,在融化期间,3种农田N2O排放量均较大,这段时期的农田是大气N2O的一个重要源;3种农田CH4排放不明显,成为大气CH4的汇。在融化期间,农田N2O排放量,旱田CH4排放量与箱内温度间均无显著相关性。而水稻田CH4排放量与箱内温度呈显著负相关,相对于生长季来说,这是土壤融化期间的特定现象。

Flux of nitrous oxide and methane were measured in the lower reaches of Liaohe Plain by using static cnambet-gas chromatographic techniques in thawing period. The plots included maize, soybean and paddy fields. The results showed that the flux of nitrous oxide in the three plots were high in the period indicating important N2O-releasing sources. The flux of methane in these plots was quite low in the period which inducated that the fields are important CH4-absorbing sinks. In thawing periods, temperature has no significant relationship with flux of nitrous oxide in the three plots. It is maybe a special phenomenon in contrast to that in the growing period.