The University of Southampton
University of Southampton Institutional Repository
Warning ePrints Soton is experiencing an issue with some file downloads not being available. We are working hard to fix this. Please bear with us.

Tracing lake pollution, eutrophication and partial recovery from the sediments of Windermere, UK, using geochemistry and sediment microfabrics

Tracing lake pollution, eutrophication and partial recovery from the sediments of Windermere, UK, using geochemistry and sediment microfabrics
Tracing lake pollution, eutrophication and partial recovery from the sediments of Windermere, UK, using geochemistry and sediment microfabrics
Many lakes undergo anthropogenically driven eutrophication and pollution leading to decreased water and sediment quality. These effects can enhance seasonally changing lake redox conditions that may concentrate potentially toxic elements. Here we report the results of a multi-method geochemical and sediment microfabric analysis applied to reconstruct the history of cultural eutrophication and pollution of the North and South Basins of Windermere, UK. Eutrophication developed from the mid-19th to the earliest 20th centuries. Enhanced lake productivity is indicated by increased sedimentary δ13C, and increased pollution by a higher concentration of metals (Pb, Hg, and As) in the sediment, likely enhanced by incorporation and adsorption to settling diatom aggregates, preserved as sedimentary laminae. In the South Basin, increasing sediment δ15N values occur in step with Zn, Hg, and Cu, linking metal enrichment to isotopically heavy nitrate (N) from anthropogenic sources. From around 1930, decreases in Mn and Fe-rich laminae indicate reduced deep-water ventilation, whereas periods of sediment anoxia increased, being most severe in the deeper North Basin. Strongly reducing sediment conditions promoted Fe and Mn reduction and Pb-bearing barite formation, hitherto only described from toxic minewastes and contaminated soils. From1980 there was an increase in indicators of bottomwater oxygenation,
although not to before 1930. But in the South Basin, the continued impacts of sewage are indicated by elevated sediment δ15N. Imaging and X-ray microanalysis using scanning electron microscopy has shown seasonal-scale redoxmineralisation ofMn, Fe, and Ba related to intermittent sediment anoxia. Elevated concentrations of these metals and As also occur in the surficial sediment and provide evidence for dynamic redoxmobilisation of potentially toxic elements to the lake water. Concentrations of As (up to 80 ppm), exceed international Sediment Quality Standards. This process may become more prevalent in the future with climate change driving lengthened summer stratification.
Cultural eutrophication, Isotopic analysis, Itrax XRF core scanning, Paleolimnology, Scanning electron microscopy, multi-method
0048-9697
1-20
Fielding, J. James
262ffd14-1f1e-4211-bac8-45aac06f5c74
Croudace, Ian
24deb068-d096-485e-8a23-a32b7a68afaf
Kemp, Alan
131b479e-c2c4-47ae-abe1-ad968490960e
Pearce, Richard
7d772b25-3ad0-4909-9a96-3a1a8111bc2f
Cotterill, Carol
cc09513b-fd65-4fa3-a95e-90fafb1aa37c
Langdon, Peter
95b97671-f9fe-4884-aca6-9aa3cd1a6d7f
Avery, Rachael
e2310327-14c0-4c0b-a03f-31207cab95c2
Fielding, J. James
262ffd14-1f1e-4211-bac8-45aac06f5c74
Croudace, Ian
24deb068-d096-485e-8a23-a32b7a68afaf
Kemp, Alan
131b479e-c2c4-47ae-abe1-ad968490960e
Pearce, Richard
7d772b25-3ad0-4909-9a96-3a1a8111bc2f
Cotterill, Carol
cc09513b-fd65-4fa3-a95e-90fafb1aa37c
Langdon, Peter
95b97671-f9fe-4884-aca6-9aa3cd1a6d7f
Avery, Rachael
e2310327-14c0-4c0b-a03f-31207cab95c2

Fielding, J. James, Croudace, Ian, Kemp, Alan, Pearce, Richard, Cotterill, Carol, Langdon, Peter and Avery, Rachael (2020) Tracing lake pollution, eutrophication and partial recovery from the sediments of Windermere, UK, using geochemistry and sediment microfabrics. Science of the Total Environment, 722, 1-20, [137745]. (doi:10.1016/j.scitotenv.2020.137745).

Record type: Article

Abstract

Many lakes undergo anthropogenically driven eutrophication and pollution leading to decreased water and sediment quality. These effects can enhance seasonally changing lake redox conditions that may concentrate potentially toxic elements. Here we report the results of a multi-method geochemical and sediment microfabric analysis applied to reconstruct the history of cultural eutrophication and pollution of the North and South Basins of Windermere, UK. Eutrophication developed from the mid-19th to the earliest 20th centuries. Enhanced lake productivity is indicated by increased sedimentary δ13C, and increased pollution by a higher concentration of metals (Pb, Hg, and As) in the sediment, likely enhanced by incorporation and adsorption to settling diatom aggregates, preserved as sedimentary laminae. In the South Basin, increasing sediment δ15N values occur in step with Zn, Hg, and Cu, linking metal enrichment to isotopically heavy nitrate (N) from anthropogenic sources. From around 1930, decreases in Mn and Fe-rich laminae indicate reduced deep-water ventilation, whereas periods of sediment anoxia increased, being most severe in the deeper North Basin. Strongly reducing sediment conditions promoted Fe and Mn reduction and Pb-bearing barite formation, hitherto only described from toxic minewastes and contaminated soils. From1980 there was an increase in indicators of bottomwater oxygenation,
although not to before 1930. But in the South Basin, the continued impacts of sewage are indicated by elevated sediment δ15N. Imaging and X-ray microanalysis using scanning electron microscopy has shown seasonal-scale redoxmineralisation ofMn, Fe, and Ba related to intermittent sediment anoxia. Elevated concentrations of these metals and As also occur in the surficial sediment and provide evidence for dynamic redoxmobilisation of potentially toxic elements to the lake water. Concentrations of As (up to 80 ppm), exceed international Sediment Quality Standards. This process may become more prevalent in the future with climate change driving lengthened summer stratification.

Text
Fielding_etal_2020_Accepted_Manuscript - Accepted Manuscript
Restricted to Repository staff only until 18 March 2022.
Request a copy
Text
1-s2.0-S0048969720312560-main - Version of Record
Restricted to Repository staff only
Request a copy
Text
Tracing lake pollution, eutrophication and partial recovery from the sediments ofWindermere, UK, using geochemistry and sediment microfabrics
Restricted to Repository staff only
Request a copy
Text
Fielding_etal_2020_Accepted_Manuscript2
Download (20MB)

More information

Accepted/In Press date: 3 March 2020
e-pub ahead of print date: 9 March 2020
Published date: 20 June 2020
Keywords: Cultural eutrophication, Isotopic analysis, Itrax XRF core scanning, Paleolimnology, Scanning electron microscopy, multi-method

Identifiers

Local EPrints ID: 438999
URI: http://eprints.soton.ac.uk/id/eprint/438999
ISSN: 0048-9697
PURE UUID: 7f7604a3-8d49-4b57-9be6-d717f2210eec
ORCID for Peter Langdon: ORCID iD orcid.org/0000-0003-2724-2643
ORCID for Rachael Avery: ORCID iD orcid.org/0000-0002-4439-4174

Catalogue record

Date deposited: 31 Mar 2020 16:31
Last modified: 26 Nov 2021 02:40

Export record

Altmetrics

Contributors

Author: J. James Fielding
Author: Ian Croudace
Author: Alan Kemp
Author: Richard Pearce
Author: Carol Cotterill
Author: Peter Langdon ORCID iD
Author: Rachael Avery ORCID iD

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×