No Cover Image

E-Thesis 531 views 38 downloads

Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations / KATHERINE WHITEHEAD

Swansea University Author: KATHERINE WHITEHEAD

  • Whitehead_Katherine_MRes_Thesis_Final_Embargoed_Redacted_Signature.pdf

    PDF | E-Thesis – open access

    Copyright: The author, Katherine Whitehead, 2022.

    Download (10.9MB)

Abstract

Microplastic concentration, composition, spatial distribution, and sediment characteristics are reported from green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) turtle rookeries in the Chagos Archipelago, Western Indian Ocean. Between March and July 2019, 25 sediment cores (60 cm depth by...

Full description

Published: Swansea 2022
Institution: Swansea University
Degree level: Master of Research
Degree name: MRes
Supervisor: Esteban, Nicole ; Stokes, Kimberley ; Esteban, Peter
URI: https://cronfa.swan.ac.uk/Record/cronfa60411
Tags: Add Tag
No Tags, Be the first to tag this record!
first_indexed 2022-07-08T09:51:13Z
last_indexed 2023-01-13T19:20:31Z
id cronfa60411
recordtype RisThesis
fullrecord <?xml version="1.0" encoding="utf-8"?><rfc1807 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><bib-version>v2</bib-version><id>60411</id><entry>2022-07-08</entry><title>Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations</title><swanseaauthors><author><sid>051ca82b020e8a816f9378caf804cb08</sid><firstname>KATHERINE</firstname><surname>WHITEHEAD</surname><name>KATHERINE WHITEHEAD</name><active>true</active><ethesisStudent>false</ethesisStudent></author></swanseaauthors><date>2022-07-08</date><abstract>Microplastic concentration, composition, spatial distribution, and sediment characteristics are reported from green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) turtle rookeries in the Chagos Archipelago, Western Indian Ocean. Between March and July 2019, 25 sediment cores (60 cm depth by 10 cm diameter) were extracted from the turtle nesting line on five beaches. This study reports the highest beach microplastic concentration recorded in the literature to date (0 – 2 cm depth; mean 371,000 particles/m3 ± 114,000 s.e.). Furthermore, with microplastic concentrations, orders of magnitude higher in both the surface layers and at turtle nesting depth than global reports; Chagos may have the highest microplastic concentrations in beach sand yet recorded. Boddam and Egmont beaches accounted for 91% of the total concentration recorded and very few microplastics were found on Nelson and Parasol Islands (5 particles). High variability was observed between stations with concentrations differing by an order of magnitude on Diego Garcia Island. Smaller microplastics were discovered in higher proportions (68%; 0.15 – 0.49 mm) than larger size classes (32%; 1 – 4.99 mm). Fragments were most prevalent accounting for 86.6%of the shapes recorded and polyethylene and polypropylene were the most frequently recorded polymers (46.3% and 20.6%). Beach sediment particle size varied from medium grained coarse skewed (Parasol, mean 0.47 mm; Nelson, stations 30 – 90, 0.46 mm; Diego Garcia, 0.40 mm) to symmetrical and fine skewed sediment (Egmont, mean 0.37 mm; Boddam, 0.31 mm). With the exception of Nelson Island (station 10) which is highly heterogenous, Chagos sediment is moderate to well sorted and the sediment particle size distribution is homogenous across the shoreline. This provides favourable conditions for high turtle nesting densities. The high microplastic concentrations discovered at turtle nesting depth however may be deleterious for this highly successful nesting site.</abstract><type>E-Thesis</type><journal/><volume/><journalNumber/><paginationStart/><paginationEnd/><publisher/><placeOfPublication>Swansea</placeOfPublication><isbnPrint/><isbnElectronic/><issnPrint/><issnElectronic/><keywords>Plastic pollution, marine pollution, marine turtle, endangered species, beach sediment composition</keywords><publishedDay>6</publishedDay><publishedMonth>7</publishedMonth><publishedYear>2022</publishedYear><publishedDate>2022-07-06</publishedDate><doi/><url/><notes/><college>COLLEGE NANME</college><CollegeCode>COLLEGE CODE</CollegeCode><institution>Swansea University</institution><supervisor>Esteban, Nicole ; Stokes, Kimberley ; Esteban, Peter</supervisor><degreelevel>Master of Research</degreelevel><degreename>MRes</degreename><degreesponsorsfunders>Darwin Plus programme; Grant number: DPLUS090</degreesponsorsfunders><apcterm/><funders/><projectreference/><lastEdited>2024-07-11T14:21:43.1084136</lastEdited><Created>2022-07-08T10:45:54.1561857</Created><path><level id="1">Faculty of Science and Engineering</level><level id="2">School of Biosciences, Geography and Physics - Biosciences</level></path><authors><author><firstname>KATHERINE</firstname><surname>WHITEHEAD</surname><order>1</order></author></authors><documents><document><filename>60411__24501__e546d75e43614eefbbef7e33dd3be6f0.pdf</filename><originalFilename>Whitehead_Katherine_MRes_Thesis_Final_Embargoed_Redacted_Signature.pdf</originalFilename><uploaded>2022-07-08T10:59:41.0963468</uploaded><type>Output</type><contentLength>11428173</contentLength><contentType>application/pdf</contentType><version>E-Thesis – open access</version><cronfaStatus>true</cronfaStatus><embargoDate>2023-07-08T00:00:00.0000000</embargoDate><documentNotes>Copyright: The author, Katherine Whitehead, 2022.</documentNotes><copyrightCorrect>true</copyrightCorrect><language>eng</language></document></documents><OutputDurs/></rfc1807>
spelling v2 60411 2022-07-08 Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations 051ca82b020e8a816f9378caf804cb08 KATHERINE WHITEHEAD KATHERINE WHITEHEAD true false 2022-07-08 Microplastic concentration, composition, spatial distribution, and sediment characteristics are reported from green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) turtle rookeries in the Chagos Archipelago, Western Indian Ocean. Between March and July 2019, 25 sediment cores (60 cm depth by 10 cm diameter) were extracted from the turtle nesting line on five beaches. This study reports the highest beach microplastic concentration recorded in the literature to date (0 – 2 cm depth; mean 371,000 particles/m3 ± 114,000 s.e.). Furthermore, with microplastic concentrations, orders of magnitude higher in both the surface layers and at turtle nesting depth than global reports; Chagos may have the highest microplastic concentrations in beach sand yet recorded. Boddam and Egmont beaches accounted for 91% of the total concentration recorded and very few microplastics were found on Nelson and Parasol Islands (5 particles). High variability was observed between stations with concentrations differing by an order of magnitude on Diego Garcia Island. Smaller microplastics were discovered in higher proportions (68%; 0.15 – 0.49 mm) than larger size classes (32%; 1 – 4.99 mm). Fragments were most prevalent accounting for 86.6%of the shapes recorded and polyethylene and polypropylene were the most frequently recorded polymers (46.3% and 20.6%). Beach sediment particle size varied from medium grained coarse skewed (Parasol, mean 0.47 mm; Nelson, stations 30 – 90, 0.46 mm; Diego Garcia, 0.40 mm) to symmetrical and fine skewed sediment (Egmont, mean 0.37 mm; Boddam, 0.31 mm). With the exception of Nelson Island (station 10) which is highly heterogenous, Chagos sediment is moderate to well sorted and the sediment particle size distribution is homogenous across the shoreline. This provides favourable conditions for high turtle nesting densities. The high microplastic concentrations discovered at turtle nesting depth however may be deleterious for this highly successful nesting site. E-Thesis Swansea Plastic pollution, marine pollution, marine turtle, endangered species, beach sediment composition 6 7 2022 2022-07-06 COLLEGE NANME COLLEGE CODE Swansea University Esteban, Nicole ; Stokes, Kimberley ; Esteban, Peter Master of Research MRes Darwin Plus programme; Grant number: DPLUS090 2024-07-11T14:21:43.1084136 2022-07-08T10:45:54.1561857 Faculty of Science and Engineering School of Biosciences, Geography and Physics - Biosciences KATHERINE WHITEHEAD 1 60411__24501__e546d75e43614eefbbef7e33dd3be6f0.pdf Whitehead_Katherine_MRes_Thesis_Final_Embargoed_Redacted_Signature.pdf 2022-07-08T10:59:41.0963468 Output 11428173 application/pdf E-Thesis – open access true 2023-07-08T00:00:00.0000000 Copyright: The author, Katherine Whitehead, 2022. true eng
title Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations
spellingShingle Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations
KATHERINE WHITEHEAD
title_short Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations
title_full Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations
title_fullStr Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations
title_full_unstemmed Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations
title_sort Distribution of microplastics on remote, isolated islands of the Chagos Archipelago; globally and regionally significant nesting sites of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations
author_id_str_mv 051ca82b020e8a816f9378caf804cb08
author_id_fullname_str_mv 051ca82b020e8a816f9378caf804cb08_***_KATHERINE WHITEHEAD
author KATHERINE WHITEHEAD
author2 KATHERINE WHITEHEAD
format E-Thesis
publishDate 2022
institution Swansea University
college_str Faculty of Science and Engineering
hierarchytype
hierarchy_top_id facultyofscienceandengineering
hierarchy_top_title Faculty of Science and Engineering
hierarchy_parent_id facultyofscienceandengineering
hierarchy_parent_title Faculty of Science and Engineering
department_str School of Biosciences, Geography and Physics - Biosciences{{{_:::_}}}Faculty of Science and Engineering{{{_:::_}}}School of Biosciences, Geography and Physics - Biosciences
document_store_str 1
active_str 0
description Microplastic concentration, composition, spatial distribution, and sediment characteristics are reported from green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) turtle rookeries in the Chagos Archipelago, Western Indian Ocean. Between March and July 2019, 25 sediment cores (60 cm depth by 10 cm diameter) were extracted from the turtle nesting line on five beaches. This study reports the highest beach microplastic concentration recorded in the literature to date (0 – 2 cm depth; mean 371,000 particles/m3 ± 114,000 s.e.). Furthermore, with microplastic concentrations, orders of magnitude higher in both the surface layers and at turtle nesting depth than global reports; Chagos may have the highest microplastic concentrations in beach sand yet recorded. Boddam and Egmont beaches accounted for 91% of the total concentration recorded and very few microplastics were found on Nelson and Parasol Islands (5 particles). High variability was observed between stations with concentrations differing by an order of magnitude on Diego Garcia Island. Smaller microplastics were discovered in higher proportions (68%; 0.15 – 0.49 mm) than larger size classes (32%; 1 – 4.99 mm). Fragments were most prevalent accounting for 86.6%of the shapes recorded and polyethylene and polypropylene were the most frequently recorded polymers (46.3% and 20.6%). Beach sediment particle size varied from medium grained coarse skewed (Parasol, mean 0.47 mm; Nelson, stations 30 – 90, 0.46 mm; Diego Garcia, 0.40 mm) to symmetrical and fine skewed sediment (Egmont, mean 0.37 mm; Boddam, 0.31 mm). With the exception of Nelson Island (station 10) which is highly heterogenous, Chagos sediment is moderate to well sorted and the sediment particle size distribution is homogenous across the shoreline. This provides favourable conditions for high turtle nesting densities. The high microplastic concentrations discovered at turtle nesting depth however may be deleterious for this highly successful nesting site.
published_date 2022-07-06T14:21:42Z
_version_ 1804289025106771968
score 11.037581

Similar Items