257-3 Photoacoustic Infrared Spectroscopy to Continuously Measure Nitrous Oxide and Ammonia Emissions From Soil.



Tuesday, October 18, 2011
Henry Gonzalez Convention Center, Hall C, Street Level

Curtis Ransom, Joshua LeMonte, Bryan Hopkins, Tobin Story, Von Jolley and Richard Terry, Brigham Young University, Provo, UT

Although N is beneficial and essential for life, it is also a common atmospheric pollutant as nitrous oxide (N2O) and ammonia (NH3)—contributed largely from N fertilization. Polymer-coated urea (PCU) fertilizer is a promising controlled release fertilizer that provides improved N-release timing. Glasshouse studies were conducted to compare N2O and NH3 emissions from PCU and uncoated urea to an untreated control utilizing a non-static, non-flow-through chamber in conjunction with photoacoustic infrared spectroscopy (PAIRS) for gas collection and analysis. Three short-term 20-Day Studies with sand, sandy loam, and loam soils and a full-term 45 Day Study with loam soil were completed. Volatilization of NH3 was reduced by 72% and 22% in the sandy loam and loam soils, respectively, in two of the short-term studies and by 14% in the loam in the full-term study. Evolution of N2O was reduced by 42% and 63% in the sandy loam and loam soils of the short-term studies and by 99% in the loam soil of the full-term study. Overall, PCU decreased gaseous losses of N following fertilization while providing a steady supply of N to the plant. Photoacoustic infrared spectroscopy is a viable analysis method that gives higher temporal resolution analysis than is typically reported.

See more from this Division: S04 Soil Fertility & Plant Nutrition
See more from this Session: Global Importance and Progress of Reducing Anthropogenic Emissions of Nitrous Oxide From Cropping Systems: II