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Nutrient fluxes between the bed and the water column

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    This dataset consists of measurements of 224Ra and macronutrients in core top water, porewaters and sediments, as well as calculated 224Ra and macronutrient fluxes (via 224Ra/228Th disequilibrium) from benthic incubations of replicate mesocosms containing selected benthic macrofauna. The experiments were conducted at the Biodiversity Ecosystem Futures Facility (BEFF lab) at the National Oceanography Centre Southampton during 2022. Sediment was collected from Rame Mud, Plymouth, and benthic organisms were collected from Rame Mud and from Loch Linhe, Scotland. For each incubation, homogenised, sieved (500 µm) sediment was added to a mesocosm to 10 cm depth, overlain by approximately 15 cm (approx. 1.3 L) seawater (0.45 µm filtered, UV sterilised, salinity 33), and left to settle for 24 hours before conducting a full water exchange. After water exchange, 1 individual of either Paraleptopentacta elongata , Edwardsia claparedii, Turritellinella tricarinata, or Amphiura chiajei was weighed and morphological measurements were taken before being added to the mesocosm. 3 replicates containing 1 individual were run for each species, in addition to 3 replicate control mesocosms containing no macrofauna. All mesocosms were continually aerated and maintained in a temperature-controlled water bath for 10 days under a 12:12h on/off light cycle. On days 4 and 8, 2.5ml of a mixed Phaeodactylum tricornutum: Tetraselmis suecica phytoplankton culture was added to all mesocosms. For a subset of mesocosms (mesocosms 14 and 15 ), daily water column nutrient samples (10 ml, 0.2 µm filtered) were taken ~5 cm below the water surface and frozen at -20°C for subsequent analysis. Experiments 1 & 2 were set up in the same manner, except that in experiment 2 only one species was included, but at higher replication (8 replicate mesocosms containing 1 individual each of E. claparedii + 1 control mesocosm). Water samples for macronutrient concentrations were analysed using a QuAAtro 39 autoanalyser (Seal Analytical) and samples for Ra activity were analysed using a Radium Delayed Coincidence Counter (RaDeCC) system.The work was conducted to quantify the influence of different species and individuals of benthic macrofauna on benthic flux, using 224Ra as a naturally occurring tracer of sediment-seawater exchange. For further information, please see the associated research paper doi: 10.1002/lno.70033

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    This dataset contains outputs of four simulations from an ocean-biogeochemistry (NEMO v.4.0.4 - ERSEM) model over the South East Asia region. Atmospheric forcing is provided by ERA5, with lateral ocean boundaries from the CMEMS global forecast. Biogeochemical tracers are initialised and forced by a combination of world ocean atlas, GloDAP, and OC-CCI data. Output is provided as daily/monthly files on {t,u,v,w}-grid. Additional monthly output used in the construction of a nitrogen budget is also provided. For all simulations, riverine input and nitrogen deposition is input into the marine environment. The four simulations include basline scenario conditions using 2015 as a reference, and then three hindcasts including nitrogen budget under current legilation, under maximum technically feasible reduction in overall nitrogen production, and under maximum technically feasible reduction in overall nitrogen production plus a change in human diet conditions. The hindcasts are used to assess future behaviour under a given scenario. The model configuration is named SAsia. The outputs were generated under the South Asian Nitrogen Hub (SANH; NE/S009019/1) project.

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    The dataset contains hydrographic and biogeochemical data, including continuous underway measurements of surface temperature, salinity, nutrients, chlorophyll and attenuance, irradiance and bathymetric depth. Underway dissolved oxygen and/or trace metal measurements were also collected on occasion. Hydrographic profiles of temperature, salinity, transmittance, fluorescence, dissolved oxygen (data often of poor quality) and scalar irradiance were undertaken, and associated water samples were routinely analysed for suspended particulate material (SPM), chlorophyll, nutrients and particulate organic carbon/particulate organic nitrogen (POC/PON). In addition, dissolved and particulate trace metals, production, contaminants, dissolved organic carbon/total dissolved nitrogen (DOC/TDN) were determined in some cases. Benthic measurements were also collected, including benthic flux determinations (microcosm experiments), sediment characterisation, pore water chemistry measurements and the quantification of the benthic macrofauna. The coastal oceanographic data set was collected along the east coast of England between Great Yarmouth and Berwick upon Tweed. Data were collected between December 1992 and July 1995 during a series of 17 RRS Challenger cruise legs. Most cruises covered two survey grids: one from Great Yarmouth to the Humber designed around the distribution of the sandbanks and a second simple zig-zag grid from the Humber to Berwick on Tweed. A large number of anchor stations, usually over one or two tidal cycles, were worked in the vicinity of the Humber mouth or the Holderness coast. Each cruise leg returned underway data and conductivity-temperature-depth (CTD) data and water bottle rosette samples from grid nodes. A Lasentech in-situ particle sizer was used to obtain grain size distributions at spot depths for each CTD station on many of the cruise legs. Box and multicorer samples were collected on approximately one third of the cruise legs. The River-Atmosphere-Coast Study (RACS) was the component of the Land Ocean Interaction Study (LOIS) programme looking at processes from the river catchment into the coastal sea. Investigators include representatives of Plymouth University, Southampton University, Liverpool University, University of East Anglia, Newcastle University, Plymouth Marine Laboratory, and the University of Wales, Bangor. All data sets collected during the RACS Challenger cruises are held by the British Oceanographic Data Centre (BODC). All underway and CTD data have been fully calibrated and quality controlled by BODC. The water sample and benthic data sets have been quality controlled by the data originators and submitted to BODC. The data are held in the BODC project database and have been published as part of a fully documented CD-ROM product.

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    The dataset contains physical, biological and chemical oceanographic measurements, and meteorological data. Hydrographic measurements include temperature, salinity, current velocities, attenuance, dissolved oxygen and fluorescence, while water samples were analysed for concentrations of nutrients, pigments, suspended particulates, metals and halocarbons. Samples were also collected for phytoplankton and zooplankton analyses, while results from production experiments are also included in the data set. These oceanographic data are supplemented by surface meteorological measurements. The data were collected at 357 sites in the NE Atlantic, 308 of which are from cruises centering on 20 W, 47 to 60 N, 16 from the Cape Verde Islands and 33 in a coccolithophore bloom just south of Iceland. Measurements were taken from 3 cruises in 1989, 6 cruises in 1990 and 2 cruises in 1991. The data were collected via (i) underway sampling (SeaSoar Undulating Oceanographic Recorder (UOR), hull-mounted acoustic Doppler current profiler (ADCP), meteorology and surface ocean parameters) of which there are 793430 records at 30 second intervals from 11 cruises and (ii) discrete sampling (conductivity-temperature-depth (CTD) and expendable bathythermograph (XBT) casts, bottle stations, net hauls, productivity incubations, stand alone pump (SAP) and sediment trap deployments, cores) of which there are 2215 deployments/experiments. The aim of the Biogeochemical Ocean Flux Study (BOFS) Community Research Project was to study the role of oceans in the global cycling of carbon. The data were collected and supplied by UK participants in the Joint Global Ocean Flux Study (JGOFS). The British Oceanographic Data Centre (BODC) had responsibility for calibrating, processing, quality controlling and documenting the data and assembling the final data set. The underway data are stored as time series for each cruise merged with the navigation data. The data are fully quality controlled. Checks were made for instrument malfunction, fouling, constant values, spikes, spurious values, calibration errors and baseline corrections. The discrete data are stored in a relational database (Oracle RDBMS), mainly as vertical profiles and are uniquely identified by a combination of deployment number and depth.

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    The dataset includes a wide range of physical, chemical and biological oceanographic parameters. Physical hydrographic measurements include temperature, salinity, optical backscatter, current velocities and turbulence, while biogeochemical measurements in the water column include dissolved oxygen, organic carbon and nitrogen, and nutrients. Biogeochemical parameters were also measured in sediment cores, while phytoplankton and zooplankton data were also collected. The marine data were supplemented by meteorological measurements including temperature, pressure, irradiance and wind. The experimental phase of the project was undertaken in the North Sea between 1998 and 1999, and data were collected at two contrasting sites: Northern North Sea (NNS, 59deg 20.0E, 1deg 00.0E) and Southern North Sea (SNS, 52deg 15.0N, 4deg 17.0E). At both locations measurements were concentrated at a central position with additional measurements being made to estimate horizontal gradients. Moored instruments were deployed at NNS from September - November 1998 and at SNS from March - May 1999. Each experiment was supported by intensive measurement series made from oceanographic ships and involving turbulence dissipation profiler, conductivity-temperature-depth (CTD) profilers, particle size profilers, optical profilers, benthic sampling and water bottle sampling. PROVESS is an interdisciplinary study of the vertical fluxes of properties through the water column and the surface and bottom boundary layers with the aim of improving understanding and quantification of vertical exchange processes in the water column. Scientists from 18 institutions distributed in 8 European countries participated in the fieldwork and modelling parts of the programme and was co-ordinated by John Howarth of the Proudman Oceanographic Laboratory. The British Oceanographic Data Centre (BODC) is responsible for assembling the data collected during the project into a comprehensive data set. The data has been organised onto a CD-ROM product available through BODC.

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    The dataset contains physical, biogeochemical and biological data, including measurements of water temperature, salinity, fluorescence, dissolved gases and current velocities; plankton samples from nets and plankton recorders; water samples for analysis of nutrients, phytoplankton, radioactivity and biogeochemical parameters; benthic cores; meteorological time series (pressure, temperature, humidity, wind velocities); atmospheric samples and ocean-atmosphere fluxes; and results from incubation experiments. The data were collected north of the Crozet Plateau in the Southern Ocean/Southwest Indian Ocean on RRS Discovery cruises D285 (3rd November - 10th December 2004) and D286 (13th December 2004 - 21st January 2005). Much of the data collection focussed on a series of Major Stations (called M1 to M10), with measurements being collected at these stations every two or three days. Conductivity-temperature-depth (CTD) casts were undertaken at each station, providing both hydrographic data and water samples from a range of depths. Other work at each Major Station included zooplankton nets, Longhurst-Hardy Plankton Recorder (LHPR) tows, sediment coring and Argo float deployment. In between Major Stations some additional CTD casts were undertaken. The SeaSoar oceanographic undulator provided further hydrographic data, while hull-mounted acoustic Doppler current profilers (ADCPs) provided current velocity data across the survey area. In addition, continuous underway measurements of hydrographic and meteorological parameters and surface water samples were collected along the cruise track. Five moorings were deployed, one of which was recovered at the end of D286. The other four, including sediment traps, current profilers and CTDs were deployed for one year. CROZEX (CROZet circulation, iron fertilization and Export production experiment) is a complex, multidisciplinary project to examine, from surface to sediment, the structure, causes and consequences of a naturally occurring annual phytoplankton bloom that forms. This collaborative project involved researchers in Ireland and the UK, and was administered by the National Oceanography Centre (NOC), Southampton. Data are managed by the British Oceanographic Data Centre. Much of the CROZEX data processing is ongoing and a number of datasets have yet to be submitted to BODC. The data described here are those presently held by BODC, with the exception of the Argo floats (these data are not expected by BODC and should be accessible via the Argo website) and the four year-long mooring deployments (data from these will be submitted to BODC in the future).

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    The data set comprises a diverse collection of physical, chemical and biological measurements, encompassing well over 1000 parameters. There are data from over 1000 conductivity-temperature-depth (CTD)/rosette stations, over 440 core profiles, over 180 sediment trap samples, over 140 net hauls and much, much more. The primary study area was a box extending to the base of the slope from Vigo to Cap Finistere. However, data are included from both further offshore (filament tracking) and from the Portuguese Margin. Measurements were taken from November 1996 to October 1999 during 33 cruise legs, involving research vessels from seven nations. Data were collected using a variety of equipment and techniques, including expendable bathythermographs (XBTs), turbulence probes, CTDs and oceanographic undulators with auxiliary sensors. These hydrographic profiles were accompanied by net hauls, plankton recorder deployments, sediment cores and a comprehensive water sampling programmes during which a wide variety of chemical and biological parameters were measured. The station data were supplemented by underway measurements of oceanographic and meteorological properties. Results from production and phosphate uptake experiments are also included in the dataset, as are bathymetric data from multibeam (swath) surveys, coastal upwelling measurements and data from moored instruments and benthic landers. The dataset also includes imagery from satellites, seabed photography and X-ray photographs of core samples. The aim of the project was study biogeochemical processes at the shelf break and to quantify the fluxes of material between the shelf and the open ocean. The project brought together over 100 scientists from 40 research centres and universities throughout Europe. The British Oceanographic Data Centre (BODC) is assembling the data sets collected during OMEX II into its project database system and the data set is also available on CD-ROM.

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    The dataset comprises hydrographic data, including salinity, temperature, depth, dissolved oxygen, transmittance (for suspended sediment), chlorophyll, irradiance, and current velocities. Both oceanographic and benthic measurements of nutrients (nitrate, nitrite, silicate, phosphate and ammonium), phytoplankton and zooplankton abundance, dissolved and particulate trace metals, primary and bacterial production, sulphur compounds and halocarbons were collected, as well as atmospheric physical and chemical measurements. The data were collected in the North Sea between August 1988 and October 1990 over a series of 38 cruises on RRS Challenger. Oceanographic measurements were taken using hydrographic profilers, moored instruments and shipboard underway systems. Underway meteorological data were also collected in addition to a comprehensive atmospheric sampling programme. Both continuous and discrete water samples were collected, providing biogeochemical and biological data. These were supplemented by net hauls. Benthic processes were investigated with sediment cores taken on eight survey cruises at six sites of varied character, three being in the area of summer stratification. Water and benthic sample analyses were supplemented by results of seabed and shipboard incubation experiments. The North Sea Project evolved from a NERC review of shelf seas research, which identified the need for a concerted multidisciplinary study of circulation, transport and production. The Proudman Oceanographic Laboratory (POL), now the National Oceanography Centre (NOC) hosted the project. It involved over 200 scientists and support staff from the Natural Environment Research Council (NERC), the Ministry of Agriculture, Fisheries and Food (MAFF - now DEFRA) and other academic institutes. The data are held at the British Oceanographic Data Centre and are available on CD-ROM.