Abstract

Emissions of ammonia (NH₃), nitrous oxide (N₂O) and methane (CH₄) from livestock production may be measured for different reasons and in consequence reported in a wide range of units. For the purpose of compiling national inventories of emissions of those gases, emissions from buildings and stores usually need to be expressed per animal or as a proportion of nitrogen (N) (NH₃ and N₂O) or volatile solids (VS) (CH₄) excreted or stored. Much of the published data on gaseous emissions from livestock production is not reported in units that can be readily used for inventory compilation. This paper provides guidance for researchers wishing to convert a wide range of emission units into emission factors (EFs) and opens up opportunities for increased use of published data. We developed our methodology using reported emissions from housing and storage systems compiled from studies for the DATAMAN database so that we could convert reported emissions into agreed EFs referred to as 'required EFs' (RqEFs). Required EFs were either derived using data reported in the associated publication or estimated, using default data (e.g. annual N excretion by a particular type of livestock).

The approach greatly increased the number of RqEFs. For example, the number of RqEFs of N₂O-N from livestock buildings as a proportion of excreted N increased from 16 to 326, while the number of N₂O RqEFs from manure stores as a proportion of stored N increased from 126 to 353.

For two subsets of NH₃-N emissions from livestock buildings and from slurry stores there were very good correlations between emissions estimated using the methodology we developed and reported emissions (R² = 0.97 and 0.97, respectively). We include a list of recommended information for inclusion in publications reporting emissions that will enable other workers to utilize this methodology.

摘要

畜牧生产中氨 (NH ₃ )、一氧化二氮 (N ₂ O) 和甲烷 (CH ₄ ) 的排放可能出于不同的原因进行测量，并因此以多种单位进行报告。为了编制这些气体的国家排放清单，建筑物和商店的排放通常需要表示为每只动物或氮（N）（NH ₃和 N ₂ O）或挥发性固体（VS）（CH ₄) 排泄或储存。许多已公布的畜牧生产气体排放数据并未以易于用于清单编制的单位报告。本文为希望将各种排放单位转换为排放因子 (EF) 的研究人员提供了指导，并为更多地使用已发布数据开辟了机会。我们使用从 DATAMAN 数据库研究汇编的住房和存储系统报告的排放量开发了我们的方法，以便我们可以将报告的排放量转换为商定的 EFs，称为“所需 EFs”（RqEFs）。所需的 EF 要么使用相关出版物中报告的数据得出，要么使用默认数据（例如特定类型牲畜的年度氮排泄量）估计。

该方法大大增加了 RqEF 的数量。例如，畜舍中 N ₂ O-N的 RqEF 数量占排泄 N 的比例从 16 增加到 326，而粪便仓库中 N ₂ O RqEF的数量占储存 N 的比例从 126 增加到 353。

对于来自牲畜建筑物和泥浆库的 NH ₃ -N 排放的两个子集，使用我们开发的方法估计的排放和报告的排放之间存在非常好的相关性（分别为R ² = 0.97 和 0.97）。我们在报告排放量的出版物中包含了一份推荐信息，这些信息将使其他工人能够使用这种方法。