A so-called 'Deep Water Incubator' was developed together with our long-term collaborator Mike Zubkov (NOC Southampton). The rational behind such an incubator is the in situ incubation of isotope-labeled substrates in the meso- and bathypelagic ocean instead of conducting incubations on deck. The approach could help to minimize decompression artifacts during incubation and thereby leading to overestimated turn-over rates of carbon and nitrogen compounds.
The Incubator is based on a rig with 6 pairs of interconnected modified Niskin-bottles, a mixing system based on salinity pumps, a CTD unit from Seabird and a deck-controlled mechanical attachment of tubes containing tracer- or fixative solution. The latter allows the precise regulation of incubation times at in situ conditions.
A first prototype of the incubator was deployed in October and November 2016 in the oligotrophic Northern Atlantic Gyre. Although first results are promising further improvements and modifications are necessary for the next deployment.