Submitted to: Journal of Environmental Quality
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/11/2011
Publication Date: 3/1/2011
Citation: Brandt, R.C., Elliott, H.A., Adviento-Borbe, M.A., Wheeler, E.F., Kleinman, P.J., Beegle, D.B. 2011. Influence of manure application method on odor emissions. Journal of Environmental Quality. 40:431-437. Interpretive Summary: Application of manure to no-till soils presents a variety of concerns to farmers, one of the most compelling being nuisance odor emissions. New technologies to incorporate manure into no-till soils promise to overcome nuisance odor concerns of conventional application methods. This study quantified differences in odor emissions with an array of manure application methods, highlighting the effectiveness of shallow injection methods in minimizing odor emissions.
Technical Abstract: Surface application of manure in reduced tillage systems can serve as a major source of nuisance odors. An investigation was undertaken to evaluate odor emissions associated with various technologies that incorporate manure with minimal soil disturbance. Dairy manure slurry was applied by five methods in a 3.05 m swath to grassland in 61 m diameter circles. Field olfactometer instruments were used to collect dilution-to-threshold (D/T) observations from the center of each circle using four odor assessors taking four readings each over a 10-min period. The Best Estimate Threshold D/T (BET10) was calculated for each application methods and an untreated control. Field odor panel observations were performed before application and at <1 h, 2-4 h, and ~24 h after spreading. Whole air samples were simultaneously collected for laboratory dynamic olfactometer evaluation using the triangular forced-choice method. The BET10 of the field olfactometer data showed D/T levels decreased from surface broadcast to aeration infiltration to chisel incorporation to direct ground injection and shallow disk injection to the unamended control. This sequence closely followed laboratory triangular forced-choice odor panel results (r = 0.83). Odor reduction benefits relative to broadcasting persisted at 24 h for all methods except aeration infiltration, and odors associated with direct ground injection were not statistically different than the untreated control.