You are here:
Characterization of Reactive Nitrogen Emissions from Turfgrass
Citation:
Nahas, A., Johnt Walker, F. Yelverton, AND V. Aneja. Characterization of Reactive Nitrogen Emissions from Turfgrass. American Geophysical Union, Washington,DC, December 10 - 14, 2018.
Impact/Purpose:
Turfgrass management is a multibillion-dollar industry that is projected to grow due to strong demand for residential and commercial properties as well as golf courses. However, intensive use of irrigation, fertilizers, and pesticides for maintaining the aesthetic value of turfgrass has environmental impacts, including the emission of nitrogen trace gases that contribute to atmospheric PM and ozone formation (NH3 and NO), as well as radiative forcing (N2O). Additional field measurements and modeling are needed to improve emission estimates for these urban reactive nitrogen sources and to develop turfgrass management practices that minimize emissions.
Description:
This study is aimed at characterizing seasonal emissions of three reactive nitrogen (Nr) species, i.e., ammonia (NH3), nitric oxide (NO), and nitrous oxide (N2O), from turfgrass over the course of a year. Fluxes were measured over tall fescue following a randomized complete block design with 10 replicates of three N-fertilizer (2.3% ammoniacal N, 22.7% urea N) treatments (0, 36.5, and 73 kg N ha-1 yr-1). Preliminary results indicate that the largest Nr emission flux is attributed to NH3 (55.0 ± 10.5 ng N m-2 s-1), followed by N2O (27.2 ± 5.4 ng N m-2 s-1) and NO (26.0 ± 4.6 ng N m-2 s-1). Highest NH3 and NO emissions were observed in plots receiving the most fertilizer and displayed a positive relationship with soil temperature, while the pattern of N2O emissions was less consistent across treatments. Future work will examine the influence of other factors on emissions, including soil moisture and chemistry. In the second phase of the project, field measurements will be coupled with a process-based biogeochemical model to assess potential turfgrass management options for minimizing reactive N emissions.