Development of an assessment strategy to determine the ammonia emission from dairy cow houses

National (Netherlands) and international policy aim to decrease the ammonia emission from dairy production. Measures to reduce emissions are under development, e.g. feeding strategies, covering of slurry pits, and new designs of floors for walking alleys in dairy cow houses. For various reasons good assessment of the emission reduction, and by that the effectiveness of a measure, is difficult and costly. In addition, the emission from traditional, apparently the same, cubicle houses varies strongly.

In the ideal situation the ammonia emission from an arbitrary cubicle dairy cow house can be assessed with sufficient accuracy and with limited time and costs. The house is either traditional or with reduction measures. Moreover, the assessed emission level can be corrected for 1) standardized outdoor climate conditions and 2) effects of specific circumstances, in order to 3) distinguish the effect of specific reduction measures from other effects and sources of variation. This PhD is a first step towards this final goal.

Focus of this PhD, and the main objective, is to develop an ‘ammonia assessment strategy’. This strategy is an emission model in combination with measurements of key variables of the ammonia emission processes under practical circumstances. The goal of this strategy is to determine the ammonia emission in a precise and cost effective way in a dairy cow house. The strategy should apply for any dairy cow house with a specific design, at a specific location, with specific climate conditions.