Atmospheric pollution caused by the intensive rearing of farm animals affects the global environment, human health and the welfare of farm animals. This topic has aroused increasing interest in countries such as Spain, where little research has been done until recently.
This doctoral thesis focuses on the experimental measurement of concentrations and emissions of gases (ammonia, methane, nitrous oxide and carbon dioxide) and particulate matter (PM10) in broiler and rabbit farms, chiefly in Mediterranean climate conditions, and examines the different factors affecting these emissions.
To fulfil these objectives, this thesis is composed of five different yet inter-related research studies. Firstly, the methodology followed to measure emissions is detailed. This methodology is based on a balance considering gas concentrations and ventilation flows. A procedure to analyse the uncertainty is proposed to obtain measurable indicators of the quality of the reported values. Secondly, the measurement of ventilation flows on commercial farms is described. This measurement consists of a circuit specifically designed to obtain and record information about the operation of the fans. Then, these two studies are applied to determine gas emissions in two commercial rabbit farms and one broiler facility in the Spanish Mediterranean coastal region. Finally, the influence of broiler activity on gas and particulate matter emissions is quantified in a study carried out in an experimental farm, and the applicability of an indirect method to determine ventilation flows in broiler farms based on a carbon dioxide balance was evaluated. The results obtained through these experiments and the subsequent analyses contribute to the general knowledge on gas emissions from broiler and rabbit farms, and they are highly useful to improve the national gas emission inventory.