Language selection


Gas emissions from straw covered liquid dairy manure during summer storage and autumn agitation.

VanderZaag, A.C., Gordon, R.J., Jamieson, R.C., Burton, D.L., and Stratton, G.W. (2009). "Gas emissions from straw covered liquid dairy manure during summer storage and autumn agitation.", Transactions of the ASABE, 52(2), pp. 599-608.


This study evaluated the effect of straw covers on emissions from liquid manure during storage and agitation. Emissions of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and ammonia (NH3) were measured from six tanks (6.6 m2 each) containing batch‐loaded liquid dairy manure. This was conducted between June and October 2007 in Nova Scotia, Canada. Straw was added to four of the tanks at two thicknesses (15 and 30 cm), while two tanks remained uncovered. Gas concentrations were measured using tunable diode lasers, an infrared gas analyzer, and acid traps. Fluxes were measured using steady‐state chambers. At the end of the study, one tank from each treatment was agitated. During 122 d of undisturbed storage, the covers increased emissions of CO2 and N2O. However, the 15 and 30 cm covers reduced CH4 emissions by 24% and 28% and reduced NH3 emissions by 78% and 90%, respectively. During 5 d of intermittent agitation, substantial releases of CO2, CH4, and NH3 were observed from all treatments. In this period, greenhouse gas emission reductions were relatively unchanged because releases from the control and covered tanks were similar. However, emissions of NH3 during agitation were highest from tanks that had been covered, thereby decreasing the overall emission reduction provided by the 15 and 30_cm covers to 68% and 76%, respectively. Despite elevated emissions during agitation, the results suggest that straw covers provide an overall reduction of CH4 and NH3 emissions compared to the control.

Report a problem on this page
Please select all that apply:
Date modified: