Deutsches Ozeanographisches
Datenzentrum Inventur der Poseidon-Reise POS476_477 (DOD-Ref-No.20140230)
Inventory of Poseidon Cruise POS476_477 (DOD-Ref-No.20140230)

Plattform
Platform
Reise-Nr.
Cruise-No.
Zeitraum
Period
Projekt
Project
Arbeitsgebiet
Working area
Poseidon POS476_477 17.10.2014 - 24.10.2014   Gotland Basin Baltic Sea  

Fahrtleiter
Chief Scientist
Institut
Institute
Auslaufhafen
Port of departure
Einlaufhafen
Port of return
Stationskarte
Station map
Schiffsroute
Trackchart
Pfannkuche Olaf GEOMAR Helmholtz-Zentrum fur Ozeanforschung Kiel Kiel Kiel Karte
Map
 

Ziel der Reise / Objectives of Cruise:

The combined cruises Poseidon 476-77 are follow up cruises of ALKOR 422 which was carried out in Latvian waters in 2013 in the same working area. Our general investigations focus on redox-dependent nutrient, nitrogen and trace metal cycles in the benthic boundary layer of the suboxic to anoxic eastern Gotland Basin. We aim to study release rates and inventories of phosphate and iron under varying degrees of bottom water oxygenation and to quantify source/sink mechanisms of the benthic boundary layer for nitrogen species and trace metals under changing oxygen conditions to assess potential feedbacks on upper mixed layer processes. While Alkor 422 was carried out in summer we wanted to study the changing of oxygen conditions in fall and winter. The natural gradient of bacterial mats (Beggiatoa ssp.), which are indicators of the suboxic zone were investigated during the expedition by studying various stations from anoxic to anoxic water (autumn situation). Two instruments were employed for our investigation the towed video/still-camera system OFOS (Ocan Floor Observation System) and a TV-controlled CTD/Rosette water sampler. Two small bottom observatories were deployed at 96m and 123m for nine months to monitor changes in: CTD, turbidity, chlorophyll, oxygen and currents during the winter and spring situation. The observatories will be retrieved in July 2015 with R/V Poseidon.

Messungen / Measurements

Institut
Institute
Wissenschaftler
Scientist
Anzahl
Number
Einheit
Unit
Typ der Messungen
Type of measurements
Kommentar
Comments
Daten im DOD
Data in DOD
GEOMAH Sommer Stefan 10 transects G08
Bottom photography
video films and still photos of the sea floor no
GEOMAH Sommer Stefan 14 stations G08
Bottom photography
TV-guided CTD/Rosette water sampler ; watersamples, bottom film and fotos no
GEOMAH Pfannkuche Olaf 26 stations H00
Stations
- yes
GEOMAH Sommer Stefan 14 stations H10
CTD-Stations
TV-guided CTD/Rosette water sampler ; watersamples, bottom film and fotos no

Verankerungen / Moorings

Institut
Institute
Wissenschaftler
Scientist
Typ der Messungen
Type of measurements
Kommentar
Comments
geogr.Breite
Latitude
geogr.Länge
Longitude
Daten im DOD
Data in DOD
GEOMAH Sommer Stefan D71 small bottom lander mooring period 9 month 57° 18.5' N 20° 33.0' E -
GEOMAH Sommer Stefan D71 small bottom lander mooring period 9 month 57° 20.7' N 20° 35.3' E -
GEOMAH Sommer Stefan H10 small bottom lander mooring period 9 month 57° 18.5' N 20° 33.0' E -
GEOMAH Sommer Stefan H10 small bottom lander mooring period 9 month 57° 20.7' N 20° 35.3' E -
16.11.2019