Zhou Wen-Tao, Long Wen-Fei, Mao Yan, Wang Bo-Ran, Long Pan, Xu Ying, Fu Zhi-Qiang
Crop Cultivation Scientific Observation and Experiment Station in Central China, College of Agronomy, Hunan Agricultural University, Changsha 410128, China.
Ying Yong Sheng Tai Xue Bao. 2020 Aug;31(8):2604-2612. doi: 10.13287/j.1001-9332.202008.021.
To clarify the effects of increased density and reduced nitrogen on greenhouse gas emission in double-season paddy fields under the water-saving and simple cultivation mode, we used Luliangyou 996 (early rice) and Fengyuanyou 299 (late rice) as materials to collect greenhouse gas by closed static box method, monitored the dynamics of CH and NO emissions from different combinations of increased density and reduced nitrogen for early and late rice, and explored changes in cumulative CH and NO emissions, global warming potential (GWP) and greenhouse gas intensity (GHGI) as affected by different combinations of increased density and reduced nitrogen from double-season rice fields. The results showed that the cumulative emissions of CH and NO from different combinations were significantly different. Compared with the control (CK), cumulative CH emission, GWP and GHGI in the two seasons decreased by 50.8%, 37.3%, and 42.9% for the combination of increased density and reduced nitrogen IR(the amount of nitrogen applied of early rice was 86.4 kg·hm, the density was 360000 holes·hm; the amount of nitrogen applied of late rice was 108 kg·hm, the density was 320000 holes·hm), respectively. IR of early rice had the lowest NO cumulative emission, being 33.7% lower than CK. IR(the amount of nitrogen applied of early rice was 103.2 kg·hm, the density was 320000 holes·hm; the amount of nitrogen applied of late rice was 129 kg·hm, the density was 280000 holes·hm) of late rice had the lowest NO cumulative emission, being decreased by 94.9%. IR had the lowest annual total GWP and GHGI of double-season paddy fields. Compared with other treatments of increased density and reduced nitrogen, the IR treatment, where nitrogen fertilizer in both early and late rice was reduced by 28.0%, the density of early rice was increased by 28.6%, and the density of late rice was increased by 33.3%, was an effective and safe option for simultaneously ensuring high yield and reducing greenhouse gas emissions.
为阐明节水简化栽培模式下双季稻田密度增加和减氮对温室气体排放的影响，我们以陆两优996（早稻）和丰源优299（晚稻）为材料，采用密闭静态箱法采集温室气体，监测早稻和晚稻不同密度增加与减氮组合下CH₄和N₂O排放动态，探究双季稻田不同密度增加与减氮组合对CH₄和N₂O累积排放量、全球升温潜势（GWP）及温室气体强度（GHGI）的影响。结果表明，不同组合的CH₄和N₂O累积排放量差异显著。与对照（CK）相比，密度增加减氮组合IR（早稻施氮量86.4 kg·hm⁻²，密度360000穴·hm⁻²；晚稻施氮量108 kg·hm⁻²，密度320000穴·hm⁻²）两季CH₄累积排放量、GWP和GHGI分别降低了50.8%、37.3%和42.9%。早稻的IR组合N₂O累积排放量最低，比CK低33.7%。晚稻的IR组合（早稻施氮量103.2 kg·hm⁻²，密度320000穴·hm⁻²；晚稻施氮量129 kg·hm⁻²，密度280000穴·hm⁻²）N₂O累积排放量最低，降低了94.9%。IR组合的双季稻田年总GWP和GHGI最低。与其他密度增加减氮处理相比，IR处理早稻和晚稻氮肥均减少28.0%，早稻密度增加28.6%，晚稻密度增加33.3%，是兼顾高产和减少温室气体排放的有效且安全的选择。
