Contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties
The subarctic shield near Yellowknife, Northwest Territories (NWT), is populated with thousands of small lakes (<1.5 km2) and several large lakes. Historic mining activities in the region have left a legacy of environmental impacts and widespread arsenic (As) contamination in both aquatic and ter...
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ftwlaurieruniv:oai:scholars.wlu.ca:etd-3702 2023-06-11T04:15:26+02:00 Contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties Harbinson, Jeremy 2023-01-01T08:00:00Z application/pdf https://scholars.wlu.ca/etd/2551 https://scholars.wlu.ca/context/etd/article/3702/viewcontent/Harbinson_MScThesis.pdf en eng Scholars Commons @ Laurier https://scholars.wlu.ca/etd/2551 https://scholars.wlu.ca/context/etd/article/3702/viewcontent/Harbinson_MScThesis.pdf 2 Publicly accessible Theses and Dissertations (Comprehensive) Arsenic Limnology Biogeochemistry Water Quality Yellowknife Northwest Territories Environmental Chemistry Environmental Monitoring Water Resource Management text 2023 ftwlaurieruniv 2023-05-07T16:36:21Z The subarctic shield near Yellowknife, Northwest Territories (NWT), is populated with thousands of small lakes (<1.5 km2) and several large lakes. Historic mining activities in the region have left a legacy of environmental impacts and widespread arsenic (As) contamination in both aquatic and terrestrial environments. In particular, several small subarctic lakes near Yellowknife have been previously documented to be contaminated with high levels of As. Subarctic lakes are characterized by seasonal ice-cover that can persist for more than half of the year, yet little is known about the under-ice spatial and seasonal dynamics of As cycling. The objective of this study is to contrast seasonal changes in As cycling within and among a series of lakes with different basin morphologies during ice-cover and into the ice-free seasons. In this study, a combination of data including water profile sampling, sediment cores, snow and ice measurements, and bathymetric mapping were collected in four lakes from November 2020 to October 2021. Continuous monitoring of lake physical properties (dissolved oxygen, temperature, and light) was conducted via data loggers installed at 1 m depth intervals in each lakes’ water column. Detailed profiles of water chemistry were collected monthly at the deepest part of each lake, examining numerous key water chemistry elements with a focus on dissolved and particulate As concentrations. Key results from this study indicated: 1) Distinct seasonal variation in As over the ice-on and open-water periods, 2) The important role of lake mixing regimes in the mobility of As, 3) Field evidence of Fe attenuation of As from the water column. This project contributes important information on the winter cycling of As, which will help to inform our understanding of the chemical recovery of subarctic lakes from As pollution. Text Northwest Territories Subarctic Yellowknife Wilfrid Laurier University, Ontario: Scholars Commons@Laurier Four Lakes ENVELOPE(-126.826,-126.826,54.858,54.858) Northwest Territories Yellowknife |
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Wilfrid Laurier University, Ontario: Scholars Commons@Laurier |
op_collection_id |
ftwlaurieruniv |
language |
English |
topic |
Arsenic Limnology Biogeochemistry Water Quality Yellowknife Northwest Territories Environmental Chemistry Environmental Monitoring Water Resource Management |
spellingShingle |
Arsenic Limnology Biogeochemistry Water Quality Yellowknife Northwest Territories Environmental Chemistry Environmental Monitoring Water Resource Management Harbinson, Jeremy Contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties |
topic_facet |
Arsenic Limnology Biogeochemistry Water Quality Yellowknife Northwest Territories Environmental Chemistry Environmental Monitoring Water Resource Management |
description |
The subarctic shield near Yellowknife, Northwest Territories (NWT), is populated with thousands of small lakes (<1.5 km2) and several large lakes. Historic mining activities in the region have left a legacy of environmental impacts and widespread arsenic (As) contamination in both aquatic and terrestrial environments. In particular, several small subarctic lakes near Yellowknife have been previously documented to be contaminated with high levels of As. Subarctic lakes are characterized by seasonal ice-cover that can persist for more than half of the year, yet little is known about the under-ice spatial and seasonal dynamics of As cycling. The objective of this study is to contrast seasonal changes in As cycling within and among a series of lakes with different basin morphologies during ice-cover and into the ice-free seasons. In this study, a combination of data including water profile sampling, sediment cores, snow and ice measurements, and bathymetric mapping were collected in four lakes from November 2020 to October 2021. Continuous monitoring of lake physical properties (dissolved oxygen, temperature, and light) was conducted via data loggers installed at 1 m depth intervals in each lakes’ water column. Detailed profiles of water chemistry were collected monthly at the deepest part of each lake, examining numerous key water chemistry elements with a focus on dissolved and particulate As concentrations. Key results from this study indicated: 1) Distinct seasonal variation in As over the ice-on and open-water periods, 2) The important role of lake mixing regimes in the mobility of As, 3) Field evidence of Fe attenuation of As from the water column. This project contributes important information on the winter cycling of As, which will help to inform our understanding of the chemical recovery of subarctic lakes from As pollution. |
format |
Text |
author |
Harbinson, Jeremy |
author_facet |
Harbinson, Jeremy |
author_sort |
Harbinson, Jeremy |
title |
Contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties |
title_short |
Contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties |
title_full |
Contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties |
title_fullStr |
Contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties |
title_full_unstemmed |
Contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties |
title_sort |
contrasting seasonal cycling of arsenic in a series of subarctic shield lakes with different morphometric properties |
publisher |
Scholars Commons @ Laurier |
publishDate |
2023 |
url |
https://scholars.wlu.ca/etd/2551 https://scholars.wlu.ca/context/etd/article/3702/viewcontent/Harbinson_MScThesis.pdf |
long_lat |
ENVELOPE(-126.826,-126.826,54.858,54.858) |
geographic |
Four Lakes Northwest Territories Yellowknife |
geographic_facet |
Four Lakes Northwest Territories Yellowknife |
genre |
Northwest Territories Subarctic Yellowknife |
genre_facet |
Northwest Territories Subarctic Yellowknife |
op_source |
Theses and Dissertations (Comprehensive) |
op_relation |
https://scholars.wlu.ca/etd/2551 https://scholars.wlu.ca/context/etd/article/3702/viewcontent/Harbinson_MScThesis.pdf |
op_rights |
2 Publicly accessible |
_version_ |
1768372252770828288 |