水稻田烤田期间甲烷排放规律研究

报道了在镇江丘陵区水稻生产中的烤田期间不同处理的甲烷排放特点及其与土壤水分、氧化还原电位的关系。结果表明，在烤田初期有一个甲烷排放高峰，然后很快下降，烤田后期甲烷排放接近于零；前茬施用稻草，对烤田期间甲烷排放有显著的促进作用；不同氮肥用量对甲烷排放的影响规律不明显；烤田期间甲烷排放占水稻全生育期排放量的比例，在３．８６％～１３．９２％范围内变化。

Effect of Mid season Aeration on Methane Emission of Rice Fields.

The effect of mid season aeration (in 8 days starting at the end of the rice tillage) on methane emission and the relations of soil moisture and oxidation reduction potential ( Eh ) to methane emission of rice fields were investigated in hilly area of Jurong, Jiangsu province in 1997. A peaked methane flux was observed at the beginning of the mid season aeration and the emission decreased rapidly to nil afterwards. The methane increased gradually after the recovering of floodwater layer, but the fluxes did not reach that before the aeration until harvesting. The decrease of methane fluxes was related significantly to the decrease of soil moisture and the increase of soil Eh after the start of the aeration. The fluxe peaks and the total emission during the mid season aeration were not significantly related to the N application rate, but related to the rice straw which was amended when the preceding winter wheat was sown The total methane emission during the mid season aeration accounted for 3.86%-13.92% of those emitted during the whole rice growth period.