|CHAPMAN, KATY - University Of Minnesota|
|Torbert, Henry - Allen|
Submitted to: European Agrophysical Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/25/2016
Publication Date: 10/3/2016
Citation: Chapman, K.E., Torbert III, H.A., Watts, D.B. 2016. Validation of a new method for quantification of ammonia volatilization from agricultural field plots. European Agrophysical Journal. 3(3):76-90. doi:10.17830/j.eaj.2016.03.077.
Interpretive Summary: Ammonia (NH3) volatilization from agricultural systems can be a significant mechanism of nitrogen (N) loss from soil. In addition to concerns of losing soil N, NH3 is an air pollutant. A method was demonstrated and validated for the measurement of atmospheric NH3 inside static chambers. This method utilizes glass tubes coated with a chemical that absorbs NH3 from the air and can be used as a predictor for the actual air concentration. Use of this procedure is advantageous in that it can be used to measure NH3 from small research plots and allow for comparisons of NH3 emissions from a large number of treatments without having several large scale field experiments. When using this method, a minimum of one correction factor is needed to convert from the NH3 concentration measured with the glass tube to the actual NH3 concentration. In addition, if a material that absorbs NH3 is used in the construction of the static chamber, another correction factor will need to be applied.
Technical Abstract: A low cost method of atmospheric ammonia (NH3) concentration was developed and validated for use in static chambers. This technique utilizes glass tubes coated with oxalic acid to adsorb NH3 from the air. The advantage of this procedure is that it can be used to quantify NH3 emissions from field plots for the evaluation of different methods of reducing NH3 emissions from agricultural fields. A correction factor is required to accurately estimate NH3 levels inside static chambers. In addition, if the static chambers are made of an NH3 absorbing material, another correction is required to obtain an accurate estimate of NH3 air concentration. Values measured with this technique can be used to estimate NH3 efflux rates and to determine the efficacy of agricultural practices. This method is described and validated in this manuscript.