LAUSR

Hydrogen sulfide (H2 S) emitted by livestock operations can be detrimental to human health. The storage of hog manure is a significant agricultural source of H2 S emissions. Hydrogen sulfide emissions from a ground-level mid-western hog finisher manure tank were measured for 8 to 20 d each quarter over a 15-month period. After excluding four days with outlier emissions the mean daily emission was 1.89 g H2 S m-2 d-1 . Mean daily emission was 1.39 g H2 S m-2 d-1 when the slurry surface was liquid and 3.00 g H2 S m-2 d-1 when crusted. Emissions however were not significantly different whether the surface was liquid or crusted when differences in temperature were considered. Diurnal variation in emissions was not correlated with air temperature, water vapor saturation deficit, or wind speed when the manure surface was crusted but was positively correlated with these variables when the surface was not crusted. Daily H2 S emissions were modeled according to two-film theory incorporating resistance approach with limited success. Additional emissions measurements with greater documentation of the manure liquid composition and crust characteristics are needed to assess the component transport resistances in the emissions model. This article is protected by copyright. All rights reserved.