膜下滴灌旱作水稻甲烷的排放研究

Research on Methane Emissions of Rice with Drip Irrigation under Mulch Film

采用对比观测方法,研究了膜下滴灌旱作水稻甲烷的排放变化。结果表明,膜下滴灌旱作水稻(品种为D10)土壤水分下限为0.8θ田时,观测15min内甲烷的排放量比土壤水分下限θ田条件下平均降低32%,甲烷日平均排放量则平均降低12.69%,说明土壤水分是影响甲烷的主要因素之一;12:00,甲烷排放量最大,为2.52mg/L,此时光合速率值最大,胞间CO2摩尔分数最小;16:00,甲烷排放量最小,为0.96mg/L,光合速率为次大,胞间CO2摩尔分数上升。说明温度和光合作用是影响甲烷的重要因素。

The comparative method was used to study the methane emission of rice with drip irrigation un- der mulch film. The results showed that., when the lower soil moisture limit of the D10 rice with drip irri- gation under mulch film was 0. 80θfield, the average methane emissions reduced by 32% within 15 minutes, and the average diurnal methane emissions reduced by 12.69% compared with the lower soil moisture limit of θfield, which illustrated that soil moisture was one of the main factors affecting methane. At 12.00, the methane emissions was the largest of 2.52 mg/L, photosynthetic rate was the biggest, and the intercellu- lar CO2 density was the smallest At 16.00, the methane emissions was the smallest of 0.96 mg/L, photo- synthetic rate was the second biggest, and the intercellular CO2 concentration increased, illustrating that the temperature and photosynthesis had important effects on methane emissions.