Nitric oxide (NO) is a pollution gas that plays an important role in tropospheric chemistry. Agricultural ecosystem is one of the major sources of atmospheric NO due to the use of nitrogen fertilizers.
The eddy covariance method is one of the most effective way to measure the NO exchanges between agricultural ecosystem and atmosphere. This method provides spatially averaged fluxes at the field scale and produces temporally continuous data without disturbing the measured area.
"However, the application of this method in NO is extremely limited," said Dr. WANG Kai, the lead author of a new study published in Agricultural and Forest Meteorology, "because this method needs high-precision measurement of NO concentration at sampling frequency of 10 Hz, and very few gas analyzers could do it."
WANG, with Institute of Atmospheric Physics at Chinese Academy of Sciences and his collaborators from Aerodyne Research Inc. (ARI) have developed an eddy covariance system for measuring the turbulent flux of NO, by using a closed-path gas analyzer based on the quantum cascade laser (QCL) absorption spectroscopy technique.
Read more at Institute Of Atmospheric Physics, Chinese Academy Of Sciences
Photo: Photo of the experimental field and the eddy covariance measuring system. (Photo by WANG Kai)