Multi-Year (2007-2017) Mercury (Hg) Concentration and Fluxes From Small High Arctic Rivers Impacted by Landscape Disturbance
Arctic mercury (Hg) contamination is an ongoing threat to human populations and ecosystems alike. Compared to preindustrial levels, elevated concentrations of Hg in air and water samples have been observed across the high latitudes with recent estimates demonstrating substantial Hg storage in Arctic...
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ftqueensuniv:oai:qspace.library.queensu.ca:1974/24915 2023-05-15T14:37:39+02:00 Multi-Year (2007-2017) Mercury (Hg) Concentration and Fluxes From Small High Arctic Rivers Impacted by Landscape Disturbance Pope, Michael Lamoureux, Scott Kirk, Jane Geography and Planning 2018-09-29T20:24:07Z http://hdl.handle.net/1974/24915 eng eng Canadian theses http://hdl.handle.net/1974/24915 Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada ProQuest PhD and Master's Theses International Dissemination Agreement Intellectual Property Guidelines at Queen's University Copying and Preserving Your Thesis This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner. Mercury Arctic Permafrost thesis 2018 ftqueensuniv 2020-12-29T09:09:41Z Arctic mercury (Hg) contamination is an ongoing threat to human populations and ecosystems alike. Compared to preindustrial levels, elevated concentrations of Hg in air and water samples have been observed across the high latitudes with recent estimates demonstrating substantial Hg storage in Arctic soils. Climate change is expected to have a strong impact on the stability of permafrost landscapes potentially releasing large quantities of Hg from thawed soils to surface waters. This study investigates multi-year, seasonal, and diel dynamics of total mercury (THg) and methyl mercury (MeHg) concentrations, particulate partitioning, and flux from two small High Arctic rivers, subject to permafrost disturbance, at the Cape Bounty Arctic Watershed Observatory, Nunavut, Canada. Water samples were collected from the outlet of the rivers during the melt season (2007-2017; excluding 2011, 2013-2015), and from several small hillslope tributaries with various levels of permafrost disturbance (2009, 2016, 2017). Results indicate that there are large diel and inter-annual variations in THg concentration and flux, in part due to climate-driven changes in discharge and the physical disturbance of active layer and permafrost soils. A large proportion of THg (30.5-72.5%) was particulate bound, and significant positive relationships were observed between THg, suspended sediment, discharge, and organic carbon concentrations in both rivers. MeHg concentrations were low for both rivers (0.05 ng L-1) and were poorly correlated with discharge, suspended sediment concentration or organic carbon. The timing and intensity of runoff was a dominant driver of THg flux in all years with the majority of discharge and peak THg concentrations occurring during either the brief nival freshet or uncommon late season rainfall events. These results provide a critical link between Hg stored in Arctic soils, permafrost disturbance and fluvial Hg export, with important implications for Hg cycling in a changing Arctic. M.Sc. Thesis Arctic Climate change Nunavut permafrost Queen's University, Ontario: QSpace Arctic Canada Cape Bounty ENVELOPE(-109.542,-109.542,74.863,74.863) Nunavut |
institution |
Open Polar |
collection |
Queen's University, Ontario: QSpace |
op_collection_id |
ftqueensuniv |
language |
English |
topic |
Mercury Arctic Permafrost |
spellingShingle |
Mercury Arctic Permafrost Pope, Michael Multi-Year (2007-2017) Mercury (Hg) Concentration and Fluxes From Small High Arctic Rivers Impacted by Landscape Disturbance |
topic_facet |
Mercury Arctic Permafrost |
description |
Arctic mercury (Hg) contamination is an ongoing threat to human populations and ecosystems alike. Compared to preindustrial levels, elevated concentrations of Hg in air and water samples have been observed across the high latitudes with recent estimates demonstrating substantial Hg storage in Arctic soils. Climate change is expected to have a strong impact on the stability of permafrost landscapes potentially releasing large quantities of Hg from thawed soils to surface waters. This study investigates multi-year, seasonal, and diel dynamics of total mercury (THg) and methyl mercury (MeHg) concentrations, particulate partitioning, and flux from two small High Arctic rivers, subject to permafrost disturbance, at the Cape Bounty Arctic Watershed Observatory, Nunavut, Canada. Water samples were collected from the outlet of the rivers during the melt season (2007-2017; excluding 2011, 2013-2015), and from several small hillslope tributaries with various levels of permafrost disturbance (2009, 2016, 2017). Results indicate that there are large diel and inter-annual variations in THg concentration and flux, in part due to climate-driven changes in discharge and the physical disturbance of active layer and permafrost soils. A large proportion of THg (30.5-72.5%) was particulate bound, and significant positive relationships were observed between THg, suspended sediment, discharge, and organic carbon concentrations in both rivers. MeHg concentrations were low for both rivers (0.05 ng L-1) and were poorly correlated with discharge, suspended sediment concentration or organic carbon. The timing and intensity of runoff was a dominant driver of THg flux in all years with the majority of discharge and peak THg concentrations occurring during either the brief nival freshet or uncommon late season rainfall events. These results provide a critical link between Hg stored in Arctic soils, permafrost disturbance and fluvial Hg export, with important implications for Hg cycling in a changing Arctic. M.Sc. |
author2 |
Lamoureux, Scott Kirk, Jane Geography and Planning |
format |
Thesis |
author |
Pope, Michael |
author_facet |
Pope, Michael |
author_sort |
Pope, Michael |
title |
Multi-Year (2007-2017) Mercury (Hg) Concentration and Fluxes From Small High Arctic Rivers Impacted by Landscape Disturbance |
title_short |
Multi-Year (2007-2017) Mercury (Hg) Concentration and Fluxes From Small High Arctic Rivers Impacted by Landscape Disturbance |
title_full |
Multi-Year (2007-2017) Mercury (Hg) Concentration and Fluxes From Small High Arctic Rivers Impacted by Landscape Disturbance |
title_fullStr |
Multi-Year (2007-2017) Mercury (Hg) Concentration and Fluxes From Small High Arctic Rivers Impacted by Landscape Disturbance |
title_full_unstemmed |
Multi-Year (2007-2017) Mercury (Hg) Concentration and Fluxes From Small High Arctic Rivers Impacted by Landscape Disturbance |
title_sort |
multi-year (2007-2017) mercury (hg) concentration and fluxes from small high arctic rivers impacted by landscape disturbance |
publishDate |
2018 |
url |
http://hdl.handle.net/1974/24915 |
long_lat |
ENVELOPE(-109.542,-109.542,74.863,74.863) |
geographic |
Arctic Canada Cape Bounty Nunavut |
geographic_facet |
Arctic Canada Cape Bounty Nunavut |
genre |
Arctic Climate change Nunavut permafrost |
genre_facet |
Arctic Climate change Nunavut permafrost |
op_relation |
Canadian theses http://hdl.handle.net/1974/24915 |
op_rights |
Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada ProQuest PhD and Master's Theses International Dissemination Agreement Intellectual Property Guidelines at Queen's University Copying and Preserving Your Thesis This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner. |
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1766309866325934080 |