27d1fdbd-8049-19ba-e063-0937940a6d67 English dataset British Geological Survey +44 131 667 1000 The Lyell Centre, Research Avenue South EDINBURGH LOTHIAN EH14 4AP United Kingdom enquiries@bgs.ac.uk pointOfContact 2026-03-17 UK GEMINI 2.3 http://data.bgs.ac.uk/id/dataHolding/13608317 WGS 84 (EPSG::4326) Particle Size Analysis and organic carbon content data from marine sediment samples within the Trevose Box, off southwest England, April 2023 (DEFRA funded FISP project) 2024-11-20 creation http://data.bgs.ac.uk/id/dataHolding/13608317 Particle Size Analysis (PSA) and organic carbon content data from marine sediment sampling of two plots within the Trevose Box off south-west England between 14 - 18 April 2023 before and after fishing. This DEFRA funded FISP (Fisheries Industry Science Partnerships scheme) project aimed to understand the acute effects of scallop dredging and beam trawling on seabed carbon. The project was led by Bangor University in collaboration with Imperial College London, CEFAS, Western Fish Producers Organisation and the South Western Fish Producer Organisation. The study was conducted in two areas offshore south-west England, UK. The areas were within the Trevose box, which is a management area closed to bottom fishing for the months of January, February and March each year. This allowed us to sample areas which had not been exposed to fishing immediately before our sampling which would reduce the chance of seeing any effect from our experimental fishing. One plot was designated an area that would be experimentally fished by a beam trawler, and another by a scallop dredger (Figure 1). The plots were chosen to minimise differences in depth, seabed habitat, sediment type, wave energy and tidal currents within and between them. Both were chosen where their respective types of fishing gear had been used previously, although scallop dredging has been less common in this area in recent years. The sampling from the RV Prince Madog and experimental fishing from the fishing vessels took place between 14 – 18th April 2023. Before any fishing activity took place, grab sampling was conducted in the dredge plot and in the beam trawl plot that would be later fished to varying amounts, which will be referred to as ‘Times fished’ or ‘fishing intensity’. A 0.1 m2 Day grab was used. When the day grab was onboard two cores were used to subsample the grab sample as deep as possible, these were then sliced in 1 cm intervals and frozen onboard for later carbon analysis. A homogenised sample from the day grab was also taken for Particle Size Analysis. After the ‘Before’ grab samples were taken, a beam trawler and scallop dredger towed their gear along the sampled lanes in each respective plot. The 'After’ samples were taken after that fishing activity. Please see report for full details on how the PSA and organic content values were determined. Whitton, T.A., Austin, M., Newbould, A., Kennedy, H., Allender, S., Cavan, E., Parker, R., North, C., Hatchman, J., Hiddink, J.G. (2024) The impact of mobile demersal fishing on blue carbon in seabed sediments. Report to DEFRA. https://research.bangor.ac.uk/portal/en/researchoutputs/the-impact-of-mobile-demersal-fishing-on-blue-carbon-in-seabed-sediments(1fa1845a-6669-4b5b-83e1-234a6eafc75c).html Tim Whitton Bangor University United Kingdom not available originator Jan Geert Hiddink Bangor University not available originator Alice Newbould Bangor University not available originator Susan Allender Bangor University not available originator Enquiries British Geological Survey United Kingdom not available custodian Enquiries British Geological Survey United Kingdom not available distributor Enquiries British Geological Survey United Kingdom not available pointOfContact notApplicable https://resources.bgs.ac.uk/images/geonetworkThumbs/27d1fdbd-8049-19ba-e063-0937940a6d67.png Geology GEMET - INSPIRE themes, version 1.0 2008-06-01 publication Grab samples TOC Particle size distribution Marine surveys Marine sediments BGS Thesaurus of Geosciences 2022 revision NGDC Deposited Data MEDIN Citable Data dataCentre NERC_DDC otherRestrictions no limitations The dataset is made freely available for access, e.g. via the Internet. Either no third party data / information is contained in the dataset or BGS has secured written permission from the owner(s) of any third party data / information contained in the dataset to make the dataset freely accessible. otherRestrictions The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused. There are no restrictions on the use that may be made of the dataset, although an appropriate copyright acknowledgement must be made when any part of the dataset is reproduced. Either no third party data / information is contained in the dataset or BGS has secured written permission from the owner of any third party data / information contained in the dataset to make the dataset freely available without any use constraints - inclusion of any third party data / information will affect the copyright acknowledgement that needs to be made. vector English geoscientificInformation British Geological Survey Gazetteer: Gazetteer of sea areas 2010 revision BRISTOL CHANNEL [id=2001350] British Geological Survey Gazetteer: Gazetteer of sea areas 2010 revision CELTIC SEA [id=2001353] -5.7800 -5.6100 50.5300 50.5800 2023-04-14 2023-04-18 Microsoft Excel (XLSX) Enquiries British Geological Survey United Kingdom not available distributor https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#item186571 WWW:DOWNLOAD-1.0-http--download Data download https://doi.org/10.5285/6d342aad-6b68-4345-beee-3cee4cb516c9 WWW:LINK-1.0-http--related Citation Information - Digital Object Identifier (DOI) Whitton, T., Hiddink, J.G., Newbould, A., Allender, S. (2024). Particle Size Analysis and organic carbon content data from marine sediment samples within the Trevose Box, off southwest England, April 2023 (DEFRA funded FISP project). NERC EDS National Geoscience Data Centre. (Dataset). https://doi.org/10.5285/6d342aad-6b68-4345-beee-3cee4cb516c9 information dataset dataset INSPIRE Implementing rules laying down technical arrangements for the interoperability and harmonisation of Geology 2011 publication See the referenced specification false Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 publication See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF false Each 1 cm sediment slice for carbon analysis dried at 60 °C and fractioned with a 2 mm sieve. Any fresh calcium carbonate from fauna that was retained on the 2 mm was added to the < 2 mm fraction, then the whole <2 mm fraction weighed then homogenised. Samples were acidified in 1N HCl to remove inorganic carbon. Pure CaCO3 powder were also acidified to make sure full inorganic carbon digestion occurred. Acidified samples were then rinsed and dried for CHN analysis to determine the organic carbon and nitrogen content as a % of the >2mm fraction for each slice down to 5 cm (5 slices of 0-1,1-2,3,4 and 5-6 cm intervals from the sediment surface). Sediment PSA broadly followed the procedures in Mason (2022) where the fraction > 1mm was analysed using dry sieving and those <1 mm using laser diffraction. This data in half phi size classes was then merged and analysed in GRADISTAT.