Record Details
Ammonia Volatilization from Nitrogen Fertilizers and Wastewater Reuse in the Columbia Basin
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Ammonia Volatilization from Nitrogen Fertilizers and Wastewater Reuse in the Columbia Basin |
| Names |
Del Moro, Sarah K.
(creator) Sullivan, Dan M. (advisor) Horneck, Donald A. (advisor) |
| Date Issued | 2015-06-04 (iso8601) |
| Note | Graduation date: 2016 |
| Abstract | Ammonia (NH₃) volatilization and loss from nitrogen (N) fertilizer in agriculture negatively impacts crops, farm profitability, human health and surrounding ecosystems where it is deposited. A significant source of NH₃ volatilization occurs from surface application of urea on sandy soils with low pH buffering capacity such as those in the semi-arid Columbia Basin region of Oregon and Washington. Ammonia volatilization can be mitigated by using alternative N fertilizers to urea. Effluent from food processing and energy production industries is also used on cropland as an efficient method to conserve water and nutrients. However, NH₃ emissions from effluent application have not been quantified. The objectives of this study were to: (i) quantify NH₃-N loss from urea vs. alternative N fertilizer products in a micrometeorological field study and laboratory incubation experiment, and (ii) quantify NH₃ emissions from effluent applied to crops using an inverse-dispersion micrometeorological method. The fertilizers evaluated in field and laboratory trials included urea, polymer-coated urea, sulfur-coated urea, urea treated with urease inhibitor [N-(n-butyl) thiophosphoric triamide (NBPT)] and ammonium sulfate (AS). Mixed and fused N salts were also evaluated, including a blend of urea and AS and a blend of AS:ammonium nitrate (AN). A modified passive flux method was used to estimate NH₃-N loss from fertilizers in the field experiment for 33 d after application. In the lab incubation trial, NH₃ was collected in acid for 43 d after application. In the field trial, cumulative NH₃-N loss from urea was 47% of N applied. The alternative N fertilizers reduced NH₃-N loss in both the field and laboratory, with the exception of the fused urea:AS blend. The reduction of NH₃-N loss ranged from 19 to 68% vs. urea in the field, and 16 to 98% vs. urea in the laboratory. In the second study, a backward Lagrangian stochastic (bLS) model was used to calculate NH₃ emissions from alfalfa fields receiving effluent water (average 111 mg L⁻¹ total Kjeldahl N content) generated from a potato processor, a dehydrated onion processor, and a cogeneration plant. An ultraviolet-differential optical absorption spectrometer (UV-DOAS) and three-dimensional sonic anemometer were used to monitor NH₃ concentrations, wind speed, and temperature for 43 days downwind of the field. The average NH₃-N emission rate was 1.4 kg ha⁻¹ d⁻¹ when effluent was applied vs. 0.5 kg ha⁻¹ d⁻¹ during irrigation without effluent. The greatest average NH₃-N emission rate of 6.1 kg ha⁻¹ d⁻¹ resulted from alfalfa harvest. These studies provided insight of relative NH₃ loss among a variety of alternative N fertilizers to urea. Additional N mass balance research will be required to validate the accuracy of these NH₃ loss quantifications. Compared to urea, all of the alternative fertilizers significantly reduced NH₃-N loss, with greatest benefit resulting from NO₃⁻ and NH₄⁺ fertilizer forms (> 60% reduction vs. urea). The average NH₃-N emission rate of 1.4 kg ha⁻¹ d⁻¹ observed during effluent application was nearly three times the rate observed from irrigation without effluent. This study confirmed the potential of alternative N fertilizers to reduce NH₃ emission in agriculture in conditions favoring NH₃ volatilization. This study also confirmed the need to consider NH₃ loss when reusing effluent as a nutrient source for crops. |
| Genre | Thesis/Dissertation |
| Access Condition | http://creativecommons.org/licenses/by-nd/3.0/us/ |
| Topic | Ammonia |
| Identifier | http://hdl.handle.net/1957/56356 |
