Identification

Title

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)

Abstract

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

Resource type

dataset

Resource locator

https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#item186571

name: Data

function: download

https://doi.org/10.5285/6d342aad-6b68-4345-beee-3cee4cb516c9

name: Digital Object Identifier (DOI)

function: information

Unique resource identifier

code

http://data.bgs.ac.uk/id/dataHolding/13608317

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

originating controlled vocabulary

title

GEMET - INSPIRE themes, version 1.0

reference date

date type

publication

effective date

2008-06-01

Keyword set

keyword value

Grab samples

TOC

Particle size distribution

NGDC Deposited Data

Citable Data

Marine surveys

MEDIN

Marine sediments

originating controlled vocabulary

title

BGS Thesaurus of Geosciences

reference date

date type

revision

effective date

2022

Keyword set

keyword value

Keyword set

keyword value

NERC_DDC

Geographic location

West bounding longitude

-5.7800

East bounding longitude

-5.6100

North bounding latitude

50.5800

South bounding latitude

50.5300

Extent

Extent group

authority code

title

British Geological Survey Gazetteer: Gazetteer of sea areas

reference date

date type

revision

effective date

2010

code identifying the extent

BRISTOL CHANNEL [id=2001350]

Extent group

authority code

title

British Geological Survey Gazetteer: Gazetteer of sea areas

reference date

date type

revision

effective date

2010

code identifying the extent

CELTIC SEA [id=2001353]

Temporal reference

Temporal extent

Begin position

2023-04-14

End position

2023-04-18

Dataset reference date

date type

creation

effective date

2024-11-20

Frequency of update

notApplicable

Quality and validity

Lineage

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.

Conformity

Conformity report

specification

title

INSPIRE Implementing rules laying down technical arrangements for the interoperability and harmonisation of Geology

reference date

date type

publication

effective date

2011

degree

false

explanation

See the referenced specification

Conformity report

specification

title

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

reference date

date type

publication

effective date

2010-12-08

degree

false

explanation

See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF

Data format

name of format

.xlsx

version of format

Constraints related to access and use

Constraint set

Limitations on public access

Constraint set

Limitations on public access

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.

Responsible organisations

Responsible party

organisation name

Bangor University

email address

not available

responsible party role

originator

Responsible party

organisation name

Bangor University

email address

not available

responsible party role

originator

Responsible party

organisation name

Bangor University

email address

not available

responsible party role

originator

Responsible party

organisation name

Bangor University

email address

not available

responsible party role

originator

Responsible party

organisation name

British Geological Survey

email address

not available

responsible party role

custodian

Responsible party

organisation name

British Geological Survey

email address

not available

responsible party role

distributor

Responsible party

organisation name

British Geological Survey

email address

not available

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

organisation name

British Geological Survey

full postal address

The Lyell Centre, Research Avenue South

EDINBURGH

EH14 4AP

United Kingdom

telephone number

+44 131 667 1000

email address

enquiries@bgs.ac.uk

responsible party role

pointOfContact

Metadata date

2025-03-10

Metadata language

eng