Quantifying nitrous oxide (N₂O) emissions from grazed pastures can be problematic due to the presence of hotspots and hot moments of N₂O from animal excreta and synthetic fertilisers. In this study, we quantified field scale N₂O emissions from a temperate grassland under a rotational grazing management using eddy covariance (EC) and static chamber techniques. Measurements of N₂O by static chambers were made for four out of nine grazing events for a control, calcium ammonium nitrate (CAN), synthetic urine (SU) + CAN and dung + CAN treatments. Static chamber N₂O flux measurements were upscaled to the field scale (F_{CH FIELD}) using site specific emission factors (EF) for CAN, SU+CAN and dung + CAN. Mean N₂O EFs were greatest from the CAN treatment while dung + CAN and SU + CAN emitted similar N₂O-N emissions. Cumulative N₂O-N emissions over the study period measured by F_{CH FIELD} measurements were lower than gap-filled EC measurements. Emission factors of N₂O from grazing calculated by F_{CH FIELD} and gap-filled were 0.72% and 0.96%, respectively. N₂O-N emissions were derived mainly from animal excreta (dung and urine) contributing 50% while N₂O-N losses from CAN and background accounted for 36% and 14%, respectively. The study highlights the advantage of using both the EC and static chamber techniques in tandem to better quantify both total N₂O-N losses from grazed pastures while also constraining the contribution of individual N sources. The EC technique was most accurate in quantifying N₂O emissions, showing a range of uncertainty that was seven times lower relative to that attributed to static chamber measurements, due to the small chamber sample size per treatment and highly variable N₂O flux measurements over space and time.

由于动物排泄物和合成肥料中存在热点和 N ₂ O的热点，因此量化放牧牧场的一氧化二氮 (N ₂ O) 排放量可能存在问题。在这项研究中，我们使用涡流协方差 (EC) 和静态室技术量化了轮牧管理下温带草原的田间规模 N ₂ O 排放。对于对照、硝酸铵钙 (CAN)、合成尿 (SU) + CAN 和粪便 + CAN 处理的九个放牧事件中的四个，通过静态室测量 N ₂ O。静态室 N ₂ O 通量测量被放大到现场规模（F _{CH FIELD}) 使用针对 CAN、SU+CAN 和粪便 + CAN 的现场特定排放因子 (EF)。CAN 处理的平均 N ₂ O EF 最大，而粪便 + CAN 和 SU + CAN 排放的 N ₂ O-N 排放量相似。通过 F _{CH FIELD}测量值测量的研究期间的累积 N ₂ O-N 排放量低于间隙填充 EC 测量值。F _{CH FIELD}和gap-filled计算的放牧N ₂ O排放因子分别为0.72%和0.96%。N ₂ O-N 排放主要来自动物排泄物（粪便和尿液），占 50%，而 N ₂来自 CAN 和背景的 ON 损失分别占 36% 和 14%。该研究强调了同时使用 EC 和静态室技术的优势，以更好地量化放牧牧场的N ₂ O-N总损失，同时限制单个 N 源的贡献。EC 技术在量化 N ₂ O 排放量方面最为准确，显示的不确定性范围比静态室测量低 7 倍，这是由于每次处理的室样本量小，且 N ₂ O 通量测量结果变化很大空间和时间。