Deutsches Ozeanographisches
Datenzentrum Inventur der Poseidon-Reise POS495 (DOD-Ref-No.20160079)
Inventory of Poseidon Cruise POS495 (DOD-Ref-No.20160079)

Working area
Poseidon POS495 18.02.2016 - 02.03.2016   NE Atlantic (Limit 40?W)  

Chief Scientist
Port of departure
Port of return
Station map
Fischer Gerhard Universitat Bremen, Zentrum fur Marine Umweltwissenschaften Las Palmas Las Palmas   

Ziel der Reise / Objectives of Cruise:

We performed optical, microbial, biological and geochemical studies of the water column as well as the exchange of two long-term sediment trap moorings off Cape Blanc (CB and CBi). We deployed a newly developed Bio-Optical Platform (BOP) equipped with 40 cups for time-series collection of intact marine snow particles (gel-filled cups) and combined with a high resolution particle camera to detect particle sinking rates within the sinking tube. We started to conduct process studies since about one decade. We deployed two drifting arrays around the eutrophic site CBi with cyclindrical, partly gel-filled traps. They were combined with a newly developed Infrared Particle Camera system (IRCam). To study zooplankton abundance and distribution, we intended to use the multinet with 5 nets, if possible for day- and night hauls to consider dial vertical migration of zooplankton. The studies were completed by roller tank incubation experiments and lab studies with marine snow aggregates collected by the new Marine Snow Catcher (MSC) and different types of zooplankton. This was done to study the effect of zooplankton on particle fluxes and organic carbon degradation. Respirations rates and sinking rates were determined on marine snow particles from different sources. We left Las Palmas on February 18th and reached the first station on February 20th where the sediment trap mooring CB-25 was recovered. We then sampled the water column with the rosette-CTD and deployed the IRCam, followed by the deployment of the MSC for the collection of marine snow in shallow water depths. The handnet was launched to sample zooplankton at night. Overnight, we deployed the IRCam in 100 m water depths to investigate the abundance of larger marine snow particles and zooplankton during a day-night cycle. In the early afternoon, we deployed the mooring CB-27. We then sailed about 120 nm to the east to reach the eutrophic study site CBi. On Monday morning, we recovered the mooring array CBi with two sediment traps. In the afternoon, the first drifting array DF-13 was deployed with the IRCam in about 50 m water depth and three cylindrical traps each with 4 cylinders in 100, 200 and 400 m, respectively. After sampling the upper water column, we deployed the first series of 4 in situ pumps (ISP) at site CBi for overnight sampling of suspended particles. In the morning of Tuesday, 23rd, we recovered the nearby drifting array DF-13. After sailing 30 nm to the east, we launched the IRCam, the rosette-CTD and the handnet for zooplankton collection. Three ISP were deployed overnight. On Wednesday, 24th of February, we redeployed the long term mooring CBi-14 with the Bio-Optical Platform (BOP) and two sediment traps. We deployed three ISP overnight. On early Thursday morning, we sailed 30 nm to the west for deploying the IRCam. Then we launched the rosette-CTD down to 1000 m. In the afternoon of February 25th, we sailed 75 nm to the east close to the coast in about 880 m water depth. There we deployed the IRCam, the multinet, the rosette-CTD and the Secchi disc. Later, we deployed the second drifting array DF-14. After sailing back to the site at the 880 m depth contour line, we launched the MSC, twice the handnet, followed by the multinet. Overnight, 3 in situ pumps were installed. On February, 27th, we searched for the drifting array DF-14. After the launch of the rosette-CTD and the Secchi disc nearby, we recovered the array. In the afternoon, we started to sail back to Las Palmas which we reached on March 2nd.

Messungen / Measurements

Typ der Messungen
Type of measurements
Daten im DOD
Data in DOD
MARUM Iversen Morten 10 deployment B02
Phytoplankton pigments (e.g. chlorophyll, fluorescence)
fluorometer on CTD. no
MARUM Iversen Morten 11 deployment B09
multinet and handnet, zooplankton distribution, species, flux feeding. no
MARUM Iversen Morten 4 deployment B71
Particulate organic matter (e.g. POC, PON)
marine snow catcher for the collection of marine snow aggregates. no
MARUM Fischer Gerhard 2 deployment B73
Sediment traps
2 recoveries and 2 deployments, one with Bio-Optical Platform and gels to preserve particles (M. Iversen). no
MARUM Iversen Morten 4 deployment H17
Optics (e.g. underwater light levels)
water transparency. no
MARUM Iversen Morten 12 deployment H17
Optics (e.g. underwater light levels)
infrared camera system for particle sizes and abundancies. no
MARUM Mollenhauer Gesine 4 deployment P01
Suspended matter
sampling of upper ca. 500m with three ISP at each deployment, lipid analysis of suspended particles. no

Verankerungen / Moorings

Typ der Messungen
Type of measurements
Daten im DOD
Data in DOD
MARUM Fischer Gerhard B73 deployment of 2 traps and one Bio-Optical-Platform (BOP) 20° 52.0' N 18° 45.0' W no
MARUM Fischer Gerhard B73 deployment of CB-27 with 2 traps 21° 13.0' N 20° 51.0' W no
MARUM Fischer Gerhard B73 recovery of CB-26 mesotrophic with 2 traps 21° 17.0' N 20° 51.0' W no
MARUM Fischer Gerhard B73 recovery of CBi-13 with 2 traps 20° 53.0' N 18° 44.0' W no