Size fractionated primary production measurements from CTD Niskin samples collected along the Barents Sea cruise transect, JR17007 and JR18006 (ChAOS cruises).

• Main Authors: Downes, Patrick, Dixon, Joanna
• Format: Dataset
• Language: English
• Published: NERC EDS British Oceanographic Data Centre NOC 2021
• Subjects: biota; oceans; Arctic; Arctic Ocean; Barents Sea
• Online Access: https://dx.doi.org/10.5285/c9c49b65-35eb-74dd-e053-6c86abc07ed4; https://www.bodc.ac.uk/data/published_data_library/catalogue/10.5285/c9c49b65-35eb-74dd-e053-6c86abc07ed4/

Rates of net primary production were measured at six stations in the Barents Sea during the Changing Arctic Ocean cruises JR17007 (10th July - 5th August 2018) and JR18006 (29th June - 2nd August 2019), on board the RSS James Clark Ross. At each station, six light depths were sampled corresponding to photosynthetically active radiation (PAR) percentages (100%, 50%, 25%, 15%, 3%, 1%), calculated from the surface PAR (log). Samples were collected using a rosette sampler equipped with 24 Niskin bottles (20 L) to collect water at defined depths. Rates of net primary production were estimated using the 14C incorporation technique, according to Joint & Pomeroy (1993). Per depth, triplicate samples were dispensed into 60 mL acid washed polycarbonate bottles, inoculated with 370 kBq NaH14CO3 and incubated on-deck at simulated PAR depths for 24 hours. Simultaneous dark incubations were performed as well as background measurements (T0). Incubations were terminated by sequential filtering through 20, 2 and 0.2 μm polycarbonate filters (Millipore™). Filters were fumed with HCl (37%) for 2 hours and desiccated for 12 hours prior to counting using ProSafe FC+ liquid scintillation cocktail (Meridian Biotechnologies). After being stored in the dark for approximately 12 hours, filters were counted using a liquid scintillation counter (TriCarb 3100TR).