Ammonia and greenhouse gas emissions from land application of solid beef manure and urea to corn fields in south central Nebraska

Authors: Spiehs, Mindy; CORTUS, ERIN - University Of Minnesota; RAHMAN, SHAFIQUR - North Dakota State University; SARKER, NILOY - North Dakota State University; NIRAULA, SURESH - North Dakota State University; MEHATA, MUKESH - Oklahoma State University; CHATTERJEE, AMITAVA - North Dakota State University; Parker, David

Submitted to: Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE)
Publication Type: Proceedings
Publication Acceptance Date: 6/15/2020
Publication Date: 7/12/2020
Citation: Spiehs, M.J., Cortus, E.L., Rahman, S., Sarker, N., Niraula, S., Mehata, M., Chatterjee, A., Parker, D.B. 2020. Ammonia and greenhouse gas emissions from land application of solid beef manure and urea to corn fields in south central Nebraska. In: Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE), July 12-15, 2020, Omaha, Nebraska. ASABE Paper No. 2000192. p. 1-10. https://doi.org/10.13031/aim.202000192.
DOI: https://doi.org/10.13031/aim.202000192

Interpretive Summary: Use of manure as a fertilizer recycles nutrients through the agricultural system and can improve soil health and increase crop yields compared to commercial fertilizer. However, the nutrients in manure can be quite variable. Little is known about the potential emissions of ammonia and greenhouse gases such as carbon dioxide, methane, and nitrous oxide when manure is used as a nitrogen fertilizer. A two-year study was conducted to measure gas emissions from corn fields that received beef manure to compare it to corn fields that received commercial fertilizer or no fertilizer. Two types of beef manure were used: solid beef manure and solid beef manure that contained corn stover as bedding material. Cumulative ammonia emissions were highest when commercial fertilizer was used but use of a commercial fertilizer reduced cumulative carbon dioxide emissions compared to both types of manure used as fertilizers. Differences in gas emissions from year to year emphasizes the need for long-term studies to better understand gaseous emissions from fertilizer application because small changes in crop rotation, weather and precipitation, even under irrigated conditions, resulted in different gaseous emissions. No fertilizer was able to reduce all gaseous emissions, which highlights the challenges producers face when selecting a fertilizer to use on their crop field. With similar emissions from all fertilizer treatments, producers can consider using manure as a nitrogen source to reduce costs associated with purchasing commercial fertilizer.

Technical Abstract: A two-year study was conducted to quantify ammonia (NH3) and greenhouse gas (GHG) emissions following land application of manure and commercial fertilizer to corn fields. Four treatments were evaluated: commercial fertilizer (CF), solid beef manure (SM), solid beef manure with corn stover bedding (BM), and no fertilizer (NF). The CF, SM, and BM treatments were applied in the fall to meet corn N demand. Air samples were measured following land application and at two-week intervals from planting to harvest. Sixteen plots were used with four replications per treatment. Average daily NH3 flux were greater from plots that received the CF treatment (2436 µg m-2 hr-1) compared to plots that had NF (1875 µg m-2 hr-1), SM (1857 µg m-2 hr-1) and BM (1850 µg m-2 hr-1) treatments applied. No differences were detected in daily CH4, CO2, or N2O flux due to fertilizer treatment, but all gases measured varied significantly between growing seasons. Cumulative NH3 emissions were higher for CF plots (214.3 kg ha-1) than SM (147.6 kg ha-1), BM (148.8 kg ha-1), and NF (151.5 kg ha-1). Cumulative CO2 emissions were higher for SM (5.3 Mg ha-1) and BM (4.9 Mg ha-1) plots compared to CF (2.6 Mg ha-1) and NF (2.5 Mg ha-1) treated plots. The significant differences between emissions from year to year emphasizes the need for long-term studies to better understand gaseous emissions from fertilizer application. With similar emissions from all fertilizer treatments, producers can consider using manure as a nitrogen source to reduce costs associated with purchasing commercial fertilizer.