Shelf Sea Biogeochemistry oxygen and pH microelectrode profiles.

This data set contains oxygen and pH profiles collected from NIOZ cores in the Celtic Sea across four surveys (DY008, DY021, DY030, DY034) on-board the RRS Discovery (2014-2015). The data were collected at four sampling sites (A, G, H, I) and over a spatial survey carried out on DY021. Samples were collected from the Celtic Sea across the four NERC Shelf Sea Biogeochemistry surveys (DY008, DY021, DY030, DY034) on-board the RRS Discovery (2014-2015). The author does not have any concerns over the quality of the data set and values are consistent with similar data reported in the wider literature. Samples for sediment characterisation were collected using the NIOZ box corer with 300mm diameter cylindrical barrel. Clear plastic tubes were then inserted into the sediment to collect undisturbed sediment cores with overlying water for profiling. Oxygen and pH profiles were acquired in the same core using a dual mounted motorised micromanipulator profiling head, with a Unisense pH-500 microelectrode (Kuhl and Revsbech 2001 - Revsbech and Jorgensen 1986) and an OX-500 microsensor (Revsbech 1989). The Sensor Trace Pro software (version 3.0.6) automatically drove the motorised profiling head down at 1mm intervals, resting 15 seconds at each depth interval before measuring for 3 seconds, to a maximum depth of 6cm. All probes were calibrated daily and pH profiles were offset for seawater using a pH TRIS buffer (Nemzer and Dickson 20054). The data were collected as part of the Shelf Sea Biogeochemistry (SSB) research programme as part of the Biogeochemistry, Macronutrient and Carbon Cycling in the benthic layer (BMCC) research programme. SSB was co-funded by the Natural Environment Research Council (NERC) and the Department for Environment, Food and Rural Affairs (Defra). The programme took a holistic approach to the cycling of nutrients and carbon and the controls on primary and secondary production in UK and European shelf seas, to increase understanding of these processes and their role in wider biogeochemical cycles. Sample collection in the field carried out by Briony Silburn, Dave Sivyer and Stefan Bolan (Centre for Environment Fisheries and Aquaculture Science). The British Oceanographic Data Centre (BODC) created the metadata entry and is responsible for holding master copies of the data.