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Fig. 3. Effects of decreased environmental sulfide on metabolite uptake rates (A,B)
(µmol g-1 h-1) and proton elimination rates (C)
(µequiv g-1 h-1) by Riftia pachyptila. Worms
were kept at in situ conditions (see Materials and methods) in the
aquaria until autotrophy. Gaseous hydrogen sulfide flow into the equilibration
column was turned off, and the aquarium seawater sulfide concentrations
dropped to levels below our limits of detection (approximately 5 µmol
l-1; Childress et al.,
1984). The arrow indicates the time at which gaseous sulfide flow
was stopped in the equilibration column. Rates are expressed in terms of wet
mass.
H2S, total sulfide.