Photosynthetic biofilms_1400x600
O2, H2S and pH microprofiles in biofilm

Photosynthetic biofilms

Microbial mats undergo daily cycles that are characterized by dramatic changes in oxygen, pH and H2S dynamics. The mats are highly active systems with functional layers of only a few hundred microns. To investigate the dynamics within these layers, it is important that measurements in the mat can be performed at high spatial resolution. Unisense microsensors can be made with sensor tips down to 3 µm and they are therefore very suited for studies of active systems.

Profiling schreenshot_1400x800

The microbial mat was dominated by Cyanobacteria. In light conditions, there was a pronounced oxygen production in the photic zone, where a peak in pH was also evident. H2S was found in the anoxic layer below 1,200 µm. The marked shifts in dynamics moving from light to dark conditions were captured with the Unisense microsensors. In the dark, the H2S production zone moved upwards along with a rapid decline of oxygen production in the microbial mat.

Photosynthetic biofilms fig_1400x800

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