Preface The expedition ARK XIX/3 with the German icebreaking RV ...

Fig. C14-2:
a) Metal frame carrying various hard substrates for a colonization experiment (left);
b) Subsampling of colonization trays after recovery of the free-falling device (right).
The deployment of plastic rings on the sediment surface, which were subsequently
filled up with an algae suspension followed the same approach (Fig. C14.-3a).
Sponge mimics anchored at the sediment surface to study effects of small biogenic
structures (in this case sessile epibenthic organisms) on sediment-inhabiting microorganisms
were sampled by push coring with the ROV (Fig. C14-3b).
Fig. C14-3:
a) Plastic ring anchored at the seafloor and filled with algae suspension (left);
b) Sampling of sponge mimics with a push corer handled by the ROV (right).
An in situ flume, approx. 6 m in length, was installed at the seafloor to investigate
benthic respiration and interfacial solute exchange under changing bottom current
regimes (Fig. C14-4a). According to near-bottom current data, the flume was
orientated in a SW to NE direction. With a funnel-like entrance at both ends with
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