, Volume 4, Issue 3, pp 183–202

Methane emissions along a salt marsh salinity gradient


  • Karen B. Bartlett
    • Department of BiologyThe College of William and Mary
  • David S. Bartlett
    • Atmospheric Sciences DivisionNASA Langley Research Center
  • Robert C. Harriss
    • Atmospheric Sciences DivisionNASA Langley Research Center
  • Daniel I. Sebacher
    • Atmospheric Sciences DivisionNASA Langley Research Center

DOI: 10.1007/BF02187365

Cite this article as:
Bartlett, K.B., Bartlett, D.S., Harriss, R.C. et al. Biogeochemistry (1987) 4: 183. doi:10.1007/BF02187365


The seasonal flux of methane to the atmosphere was measured at three salt marsh sites along a tidal creek. Average soil salinities at the sites ranged from 5 to 17 ppt and fluxes ranged from below detection limits (less than 0.3 mgCH4 m-2 d-1) to 259 mgCH4 m-2 d-1. Annual flux to the atmosphere was 5.6 gCH4 m-2 from the most saline site, 22.4 gCH4 m-2 from the intermediate site, and 18.2 gCH4 m-2 from the freshest of the three sites. Regression of the amount of methane in the soil with flux indicates that changes in this soil methane can account for 64% of the observed variation in flux. Data on pore water distributions of sulfate suggests that the activity of sulfate reducing bacteria is a primary control on methane flux in these transitional environments. Results indicate that relatively high emissions of methane from salt marshes can occur at soil salinities up to approximately 13 ppt. When these data are combined with other tidal marsh studies, annual CH4 flux to the atmosphere shows a strong negative correlation with the long term average soil salinity over a range from essentially fresh water to 26 ppt.

Key words

methane fluxsalt marshsalinity gradient

Copyright information

© Martinus Nijhoff/Dr W. Junk Publishers 1987