Nitrous oxide emissions from a commercial cornfield (Zea mays) measured using the eddy covariance technique
H. Huang1,J. Wang1,D. Hui2,D. R. Miller3,S. Bhattarai2,S. Dennis2,D. Smart4,T. Sammis5,and K. C. Reddy2H. Huang et al. H. Huang1,J. Wang1,D. Hui2,D. R. Miller3,S. Bhattarai2,S. Dennis2,D. Smart4,T. Sammis5,and K. C. Reddy2
1Climate and Atmospheric Science Section, Illinois State Water Survey, Prairie Research Institute, University of Illinois at Urbana–Champaign, Champaign, IL 61802, USA
2College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, TN 37209, USA
3Department of Natural Resources and Environment, University of Connecticut, Storrs, CT 06269, USA
4Department of Viticulture and Enology, University of California, Davis, CA 95616, USA
5Department of Plant and Environmental Science, New Mexico State University, Las Cruces, NM 88003, USA
1Climate and Atmospheric Science Section, Illinois State Water Survey, Prairie Research Institute, University of Illinois at Urbana–Champaign, Champaign, IL 61802, USA
2College of Agriculture, Human and Natural Sciences, Tennessee State University, Nashville, TN 37209, USA
3Department of Natural Resources and Environment, University of Connecticut, Storrs, CT 06269, USA
4Department of Viticulture and Enology, University of California, Davis, CA 95616, USA
5Department of Plant and Environmental Science, New Mexico State University, Las Cruces, NM 88003, USA
Received: 17 May 2014 – Discussion started: 08 Aug 2014 – Revised: 27 Oct 2014 – Accepted: 10 Nov 2014 – Published: 08 Dec 2014
Abstract. Increases in observed atmospheric concentrations of the long-lived greenhouse gas nitrous oxide (N2O) have been well documented. However, information on event-related instantaneous emissions during fertilizer applications is lacking. With the development of fast-response N2O analyzers, the eddy covariance (EC) technique can be used to gather instantaneous measurements of N2O concentrations to quantify the exchange of nitrogen between the soil and atmosphere. The objectives of this study were to evaluate the performance of a new EC system, to measure the N2O flux with the system, and finally to examine relationships of the N2O flux with soil temperature, soil moisture, precipitation, and fertilization events. An EC system was assembled with a sonic anemometer and a fast-response N2O analyzer (quantum cascade laser spectrometer) and applied in a cornfield in Nolensville, Tennessee during the 2012 corn growing season (4 April–8 August). Fertilizer amounts totaling 217 kg N ha−1 were applied to the experimental site. Results showed that this N2O EC system provided reliable N2O flux measurements. The cumulative emitted N2O amount for the entire growing season was 6.87 kg N2O-N ha−1. Seasonal fluxes were highly dependent on soil moisture rather than soil temperature. This study was one of the few experiments that continuously measured instantaneous, high-frequency N2O emissions in crop fields over a growing season of more than 100 days.
An EC system was assembled with a sonic anemometer and a new fast-response N2O analyzer and applied in a cornfield during a growing season. This N2O EC system provided reliable N2O flux measurements. The average flux was about 63% higher during the daytime than during the nighttime. Seasonal fluxes were highly dependent on soil moisture rather than soil temperature.
An EC system was assembled with a sonic anemometer and a new fast-response N2O analyzer and...
