| 引用本文: | 吴庆峰,郑佳舜,肖 未,等.不同耕作施氮处理对稻田N2O通量和田面水中无机氮的影响[J].灌溉排水学报,2023,42(6):25-32. |
| WU Qingfeng,ZHENG Jiashun,XIAO Wei,et al.不同耕作施氮处理对稻田N2O通量和田面水中无机氮的影响[J].灌溉排水学报,2023,42(6):25-32. |
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| 摘要: |
| 【目的】探索不同耕作施氮处理对稻田氧化亚氮（N2O）通量和田面水中无机氮质量浓度的影响。【方法】设置4种耕作方式（免耕T、微耕C、旋耕R和粉垄S）以及2个施氮量（常规施氮225 kg/hm2（N1）和减量施氮150 kg/hm2（N2））的双季水稻田间试验，测定不同时期施用氮肥后稻田N2O通量以及田面水中无机氮质量浓度，分析不同时期施用氮肥后1、3、5 d稻田N2O通量与田面水中无机氮质量浓度之间的关系。【结果】①不同时期施用氮肥后田面水中的铵态氮（NH4+-N）质量浓度较高，施用氮肥后1 d田面水中的NH4+-N快速上升到峰值后迅速下降。分蘖期和孕穗期施用氮肥后，TN1（免耕常规施氮）处理田面水中的NH4+-N较其他处理提高4.7%~532.6%。氮肥作基肥以及在分蘖期和孕穗期施用后，所有处理田面水中的硝态氮（NO3--N）和亚硝态氮（NO2--N）质量浓度较低，NO3--N质量浓度在0.08~0.20 μg/mL，NO2--N质量浓度低于0.12 μg/mL。②氮肥作基肥以及在分蘖期和孕穗期施用后，TN2处理稻田N2O通量较其他处理低。③稻田N2O通量与不同时期施用氮肥后1~5 d田面水中NH4+-N质量浓度显著负相关，相关系数为-0.509~-0.300。【结论】施用氮肥后NH4+-N是田面水中无机氮的主要形态，施用氮肥后1~5 d田面水中的NH4+-N质量浓度显著影响稻田N2O通量。 |
| 关键词: 耕作方式；施氮量；无机氮；N2O排放；稻田 |
| DOI：10.13522/j.cnki.ggps.2022657 |
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| Effects of Different Tillage and Nitrogen Applications on N2O Emission and Mineral Nitrogen in Surface Water of Paddy Field |
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WU Qingfeng, ZHENG Jiashun, XIAO Wei, LI Fusheng
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College of Agriculture, Guangxi University, Nanning 530004, China
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| Abstract: |
| 【Objective】Rice in southern China is traditionally grown in paddy fields and improving its fertilizer use efficiency and reducing greenhouse emissions is critical to helping achieve the mandatory goal of zero-increase in agrochemical application without compromising crop yield. This paper presents the findings of an experimental study on combined effect of tillage and nitrogen application on N2O emission and mineral N concentrations in surface water of the paddy fields.【Method】The experiment was conducted in a double-cropping rice field and involved four tillage treatments: zero tillage (T), micro tillage (C), rotary tillage (R), and smash ridging tillage (S). For each tillage treatment, there were two N fertilizations: conventional N application at 1 225 kg/hm2 (N1) and reducing N application to 150 kg/hm2 (N2). N2O emission and mineral N concentration in the surface water in each treatment were measured 1, 3, and 5 days after N fertilization at different growth stages of the rice.【Result】① One day after N fertilization, ammonium concentration in the surface water increased rapidly to a peak one and then declined quickly. In the conventional fertilization (N1) where N was applied at both tillering and booting stage, zero-tillage increased ammonium concentration in the surface water by 4.7%~532.6%, compared to other treatments. Overall, nitrate and nitrite concentrations in the surface water of all treatments were in the range 0.08~0.20 μg/mL and less than 0.12 μg/mL, respectively. ② Reducing N application and applying it as basal fertilization and topdressing at tillering and booting stages, TN2 reduced N2O emission more than other tillage treatments. ③ N2O emission was negatively correlated to ammonium concentration in the surface water 1~5 days after N fertilization, with the correlation coefficient varying from -0.300~-0.509, depending on the timing of the fertilization. 【Conclusion】After N fertilization, ammonium became the primary inorganic nitrogen in the surface water. Ammonium concentration of the surface water 1~5 days after the fertilization impacted N2O emissions, irrespective of the timing of the fertilization. |
| Key words: tillage method; nitrogen rate; inorganic nitrogen; N2O emission; paddy soil |
