TABLE 1

D/14C tracer ratios for the experimental treatments addressed in this studya

Sample testedRatio in:
Exponential
phase
Stationary
phase
Oxic
incubations
Anoxic
incubations
Aerobic methanotroph cultures
    M. trichosporium1.51.48
    M. sedimenti1.541.59
Methane seep sediments and carbonates
    A.Sed-5128 1.622.05
    L.Sed-5043 1.712.01
    A.Carb-5305 1.651.96
    A.Carb-5152 1.632.08
    L.Carb-5028 1.691.86
  • a Cultures of the aerobic methanotrophs M. trichosporium and M. sedimenti were tested alongside environmental samples, sediments (Sed) and carbonate rocks (Carb), from Hydrate Ridge methane seeps. “A” refers to sites of active seepage, while “L” indicates locations of low seepage activity, where clear signs of contemporary methane seepage were absent. (See the text for additional sampling details.)