Measurements of CH$_{4}$ and N$_{2}$O Fluxes at the Landscape Scale Using Micrometeorological Methods

D. Fowler, K. J. HARGREAVES, U SKIBA, R. Milne, M. S. ZAHNISER, John Moncrieff, I. J. BEVERLAND, M. W. GALLAGHER, P. Ineson, J. Garland, C. Johnson

Research output: Contribution to journalArticlepeer-review

Abstract / Description of output

Flux gradient, eddy covariance and relaxed eddy accumulation methods were applied to measure CH$_{4}$ and N$_{2}$O emissions from peatlands and arable land respectively. Measurements of N$_{2}$O emission by eddy covariance using tunable diode laser spectroscopy provided fluxes ranging from 2 to 60 $\mu $mol N$_{2}$O m$^{-2}$ h$^{-1}$ with a mean value of 22 $\mu $mol N$_{2}$O m$^{-2}$ h$^{-1}$ from 320 h of continuous measurements. Fluxes of CH$_{4}$ measured above peatland in Caithness (U.K.) during May and June 1993 by eddy covariance and relaxed eddy accumulation methods were in the range 70 to 120 $\mu $mol CH$_{4}$ m$^{-2}$ h$^{-1}$ with means of 14.7 $\mu $mol CH$_{4}$ m$^{-2}$ h$^{-1}$ and 22.7 $\mu $mol CH$_{4}$ m$^{-2}$ h$^{-1}$ respectively. Emissions of CH$_{4}$ from peatland changed with water table depth and soil temperature; increasing from 25 $\mu$mol CH$_{4}$ m$^{-2}$ h$^{-1}$ at 5% pool area to 50 $\mu $mol CH$_{4}$ m$^{-2}$ h$^{-1}$ with 30% within the flux footprint occupied by pools. A temperature response of 4.9 $\mu $mol CH$_{4}$ m$^{-2}$ h$^{-1}$ degrees C$^{-1}$ in the range 6-12 degrees C was also observed. The close similarity in average CH$_{4}$ emission fluxes reported for wetlands in Caithness, Hudson Bay and Alaska in the range 11 to 40 $\mu $mol CH$_{4}$ m$^{-2}$ h$^{-1}$ suggests that earlier estimates of CH$_{4}$ emission from high latitude wetlands were too large or that the area of high latitudes contributing to CH$_{4}$ emission has been seriously underestimated.
Original languageEnglish
Pages (from-to)339-355
Number of pages17
JournalPhilosophical Transactions A: Mathematical, Physical and Engineering Sciences
Volume351
Issue number1696
DOIs
Publication statusPublished - May 1995

Fingerprint

Dive into the research topics of 'Measurements of CH$_{4}$ and N$_{2}$O Fluxes at the Landscape Scale Using Micrometeorological Methods'. Together they form a unique fingerprint.

Cite this