Abstract Methane emissions of a grazing herd of Belgian Blue cattle were estimated per individual on the field by combining eddy covariance measurements with geolocation of the cattle and a footprint model. This method allows the measurement of outdoor non-invasive methane emissions but is complex and subject to methodological issues. Estimated emissions were 220 ±35 g CH4 LU−1 day−1 (grams of methane per livestock unit per day), where the uncertainty corresponds to the random error and does not include any possible systematic error. Cattle behavior was also monitored and presented a clear daily pattern of activity with more intense grazing after sunrise and before sunset. However, no significant methane emission pattern could be associated with it, the diurnal emission variation being lower than the measurement precision.

中文翻译：

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使用涡流协方差技术结合地理定位估算肉牛甲烷排放量

摘要 通过将涡度协方差测量与牛的地理定位和足迹模型相结合，估算了每头比利时蓝牛放牧群的甲烷排放量。这种方法允许测量室外非侵入性甲烷排放量，但很复杂并且受方法学问题的影响。估计排放量为 220 ±35 g CH4 LU−1 day−1（每头牲畜每天的甲烷克数），其中不确定性对应于随机误差，不包括任何可能的系统误差。还监测了牛的行为，并呈现出清晰的日常活动模式，日出后和日落前放牧更加激烈。然而，没有明显的甲烷排放模式与之相关，昼夜排放变化低于测量精度。