Cargando…

Experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes

Legacy arsenic (As) contamination from past mining operations remains an environmental concern in lakes of the Yellowknife area (Northwest Territories, Canada) due to its post-depositional mobility in sediment and potential for continued remobilization to surface waters. Warmer temperatures associat...

Descripción completa

Detalles Bibliográficos
Autores principales: Astles, Brittany C., Chételat, John, Palmer, Michael J., Vermaire, Jesse C.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9770359/
https://www.ncbi.nlm.nih.gov/pubmed/36542618
http://dx.doi.org/10.1371/journal.pone.0279412
_version_ 1784854579161071616
author Astles, Brittany C.
Chételat, John
Palmer, Michael J.
Vermaire, Jesse C.
author_facet Astles, Brittany C.
Chételat, John
Palmer, Michael J.
Vermaire, Jesse C.
author_sort Astles, Brittany C.
collection PubMed
description Legacy arsenic (As) contamination from past mining operations remains an environmental concern in lakes of the Yellowknife area (Northwest Territories, Canada) due to its post-depositional mobility in sediment and potential for continued remobilization to surface waters. Warmer temperatures associated with climate change in this subarctic region may impact As internal loading from lake sediments either by a direct effect on sediment porewater diffusion rate or indirect effects on microbial metabolism and sediment redox conditions. This study assessed the influence of warmer temperatures on As diffusion from contaminated sediment of two lakes with contrasting sediment characteristics using an experimental incubation approach. Sediments from Yellowknife Bay (on Great Slave Lake) contained predominately clay and silt with low organic matter (10%) and high As content (1675 μg/g) while sediments of Lower Martin Lake had high organic matter content (~70%) and approximately half the As (822 μg/g). Duplicate sediment batches from each lake were incubated in a temperature-controlled chamber, and overlying water was kept well-oxygenated while As flux from sediment was measured during four weekly temperature treatments (7°C to 21°C, at ~5°C intervals). During the experiment, As diffused from sediment to overlying water in all cores and temperature treatments, with As fluxes ranging from 48–956 μg/m(2)/day. Arsenic fluxes were greater from Yellowknife Bay sediments, which had higher solid-phase As concentrations, compared to those of Lower Martin Lake. Short-term warming did not stimulate As flux from duplicate cores of either sediment type, in contrast with reported temperature enhancement in other published studies. We conclude that warmer temperatures were insufficient to strongly enhance sediment As diffusion into overlying oxic waters. These observations are relevant for evaluating climate-warming effects on sediment As mobility in subarctic lakes with little or no thermal stratification and a well-oxygenated water column.
format Online
Article
Text
id pubmed-9770359
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-97703592022-12-22 Experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes Astles, Brittany C. Chételat, John Palmer, Michael J. Vermaire, Jesse C. PLoS One Research Article Legacy arsenic (As) contamination from past mining operations remains an environmental concern in lakes of the Yellowknife area (Northwest Territories, Canada) due to its post-depositional mobility in sediment and potential for continued remobilization to surface waters. Warmer temperatures associated with climate change in this subarctic region may impact As internal loading from lake sediments either by a direct effect on sediment porewater diffusion rate or indirect effects on microbial metabolism and sediment redox conditions. This study assessed the influence of warmer temperatures on As diffusion from contaminated sediment of two lakes with contrasting sediment characteristics using an experimental incubation approach. Sediments from Yellowknife Bay (on Great Slave Lake) contained predominately clay and silt with low organic matter (10%) and high As content (1675 μg/g) while sediments of Lower Martin Lake had high organic matter content (~70%) and approximately half the As (822 μg/g). Duplicate sediment batches from each lake were incubated in a temperature-controlled chamber, and overlying water was kept well-oxygenated while As flux from sediment was measured during four weekly temperature treatments (7°C to 21°C, at ~5°C intervals). During the experiment, As diffused from sediment to overlying water in all cores and temperature treatments, with As fluxes ranging from 48–956 μg/m(2)/day. Arsenic fluxes were greater from Yellowknife Bay sediments, which had higher solid-phase As concentrations, compared to those of Lower Martin Lake. Short-term warming did not stimulate As flux from duplicate cores of either sediment type, in contrast with reported temperature enhancement in other published studies. We conclude that warmer temperatures were insufficient to strongly enhance sediment As diffusion into overlying oxic waters. These observations are relevant for evaluating climate-warming effects on sediment As mobility in subarctic lakes with little or no thermal stratification and a well-oxygenated water column. Public Library of Science 2022-12-21 /pmc/articles/PMC9770359/ /pubmed/36542618 http://dx.doi.org/10.1371/journal.pone.0279412 Text en © 2022 Astles et al https://creativecommons.org/licenses/by/4.0/This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
spellingShingle Research Article
Astles, Brittany C.
Chételat, John
Palmer, Michael J.
Vermaire, Jesse C.
Experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes
title Experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes
title_full Experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes
title_fullStr Experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes
title_full_unstemmed Experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes
title_short Experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes
title_sort experimental investigation of short-term warming on arsenic flux from contaminated sediments of two well-oxygenated subarctic lakes
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9770359/
https://www.ncbi.nlm.nih.gov/pubmed/36542618
http://dx.doi.org/10.1371/journal.pone.0279412
work_keys_str_mv AT astlesbrittanyc experimentalinvestigationofshorttermwarmingonarsenicfluxfromcontaminatedsedimentsoftwowelloxygenatedsubarcticlakes
AT chetelatjohn experimentalinvestigationofshorttermwarmingonarsenicfluxfromcontaminatedsedimentsoftwowelloxygenatedsubarcticlakes
AT palmermichaelj experimentalinvestigationofshorttermwarmingonarsenicfluxfromcontaminatedsedimentsoftwowelloxygenatedsubarcticlakes
AT vermairejessec experimentalinvestigationofshorttermwarmingonarsenicfluxfromcontaminatedsedimentsoftwowelloxygenatedsubarcticlakes