Martin Ngwabie, Ngwa
- Department of Rural Buildings and Animal Husbandry [LBT], Swedish University of Agricultural Sciences
Research article2010Peer reviewed
Martin, Ngwabie Ngwa; Jeppsson, Knut-Håkan; Gustafsson, Gösta; Nimmermark, Sven
Gaseous emissions from livestock manure may adversely affect human and animal health as well as the surrounding environment. In an effort to understand and mitigate these emissions, the effects of different environmental factors and the addition of wood shavings on ammonia and odour emissions from fresh pig and dairy cow manure were studied. The manure was divided into two portions and wood shavings were mixed with one portion. Emissions from equal volumes of both portions were measured at different environmental conditions in a flux chamber. The manure temperature was varied between 15–30 ºC. Fresh air at temperatures between 16–26 ºC was passed at a fixed rate over the manure. The addition of wood shavings decreased the total-N and NH4+-N, but increased the pH of the manure at the end of the experiment. The temperature of the manure with wood shavings increased faster than that of the manure without wood shavings. The ammonia emission from the pig manure (0.08–0.41 mg m-2 s-1) was on average much higher than the ammonia emission from the cow manure (0–0.08 mg m-2 s-1). The odour emission from the pig manure was high (21–930 OU m-2 s-1), and significantly higher than the odour emission from the cow manure (1–6 OU m-2 s-1). A positive correlation was found between the ammonia emissions and the manure temperature. Ammonia emissions were about 2 times higher at manure temperatures of about 25 ºC compared to emissions at about 15 ºC. Odour emissions were positively correlated with the temperature of cow manure. Ammonia emissions at 25 ºC were high, while odour emissions at 25 ºC were lower than those at 20 ºC for the pig manure with wood shavings. The water vapour pressure was positively correlated to the emissions from the cow manure but not from the pig manure. The measurements indicated a positive correlation between ammonia and odour emissions for the cow manure as well as for the pig manure without wood shavings. The addition of wood shavings to animal manure does not seem to automatically mitigate ammonia or odour emissions as it also affects the temperature and the pH
Dry matter; C/N ratio; volatilisation; temperature; ammonium; Sweden
Agricultural Engineering International: the CIGR Ejournal
2010, Volume: 12, number: 3, pages: 68-81
Environmental Sciences related to Agriculture and Land-use
Agricultural Science
https://res.slu.se/id/publ/32437