Download Review of gaseous emissions of methane, nitrous oxide and ammonia, and nitrate leaching to water, from farm dairy effluent storage and application to land – Final Report

Atmospheric emissions arising from the management of dairy farm manure are generally poorly understood and quantified. New Zealand’s greenhouse gas (GHG) inventory lists emissions from farm dairy effluent, predominantly in the form of methane, as a minor contribution to total dairy farm emissions. However, recent work indicates that for some emission pathways, like methane from effluent stored in ponds, emissions are substantially underestimated. Moreover, with increasing intensification of dairy farming and the handling of larger volumes of manure, dairy farm manure emissions are likely to increase at a disproportionally larger rate, compared with overall dairy farming emissions. It is therefore imperative to better understand the magnitude and special characteristics of emissions from dairy farm manure management. Furthermore, a number of practical mitigations technologies for these emissions exist; hence, a better understanding of these emissions could enable some moderate, but cost-effective GHG emission reductions in the dairy sector.