Figure 1
From: Nitrogen fixation in distinct microbial niches within a chemoautotrophy-driven cave ecosystem

Bacterial uptake of 15N2 gas into the sulfidic sediment (PC-SedB; Table 1) collected at the cave site PC; error bars represent s.d. (n=2). Uptake of the isotope label by sediment sample amended with molybdate (performed only for the final time point, 120 h) is shown. The parallel experiment with the control without isotope label (also for the final time point, 120 h) displays no significant change in the δ15N value.