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Diatom ecological response to deposition of the 833-850 CE White River Ash (east lobe) ashfall in a small subarctic Canadian lake.

https://arctichealth.org/en/permalink/ahliterature297789
Source
PeerJ. 2019; 7:e6269
Publication Type
Journal Article
Date
2019
Author
Scott J Hutchinson
Paul B Hamilton
R Timothy Patterson
Jennifer M Galloway
Nawaf A Nasser
Christopher Spence
Hendrik Falck
Author Affiliation
Ottawa-Carleton Geoscience Center and Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada.
Source
PeerJ. 2019; 7:e6269
Date
2019
Language
English
Publication Type
Journal Article
Abstract
A
PubMed ID
30701131 View in PubMed
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Intra-lake response of Arcellinida (testate lobose amoebae) to gold mining-derived arsenic contamination in northern Canada: Implications for environmental monitoring.

https://arctichealth.org/en/permalink/ahliterature305991
Source
PeerJ. 2020; 8:e9054
Publication Type
Journal Article
Date
2020
Author
Nawaf A Nasser
R Timothy Patterson
Jennifer M Galloway
Hendrik Falck
Author Affiliation
Ottawa-Carleton Geoscience Centre and Department of Earth Sciences, Carleton University, Ottawa, ON, Canada.
Source
PeerJ. 2020; 8:e9054
Date
2020
Language
English
Publication Type
Journal Article
Abstract
Arcellinida (testate lobose amoebae) were examined from 40 near-surface sediment samples (top 0.5 cm) from two lakes impacted by arsenic (As) contamination associated with legacy gold mining in subarctic Canada. The objectives of the study are two folds: quantify the response of Arcellinida to intra-lake variability of As and other physicochemical controls, and evaluate whether the impact of As contamination derived from two former gold mines, Giant Mine (1938-2004) and Tundra Mine (1964-1968 and 1983-1986), on the Arcellinida distribution in both lakes is comparable or different. Cluster analysis and nonmetric multidimensional scaling (NMDS) were used to identify Arcellinida assemblages in both lakes, and redundancy analysis (RDA) was used to quantify the relationship between the assemblages, As, and other geochemical and sedimentological parameters. Cluster analysis and NMDS revealed four distinct arcellinidan assemblages in Frame Lake (assemblages 1-4) and two in Hambone Lake (assemblages 5 and 6): (1) Extreme As Contamination (EAC) Assemblage; (2) High calcium (HC) Assemblage; (3) Moderate As Contamination (MAC) assemblages; (4) High Nutrients (HN) Assemblage; (5) High Diversity (HD) Assemblage; and (6) Centropyxis aculeata (CA) Assemblage. RDA analysis showed that the faunal structure of the Frame Lake assemblages was controlled by five variables that explained 43.2% of the total faunal variance, with As (15.8%), Olsen phosphorous (Olsen-P; 10.5%), and Ca (9.5%) being the most statistically significant (p
PubMed ID
32411528 View in PubMed
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Lacustrine Arcellinina (Testate Amoebae) as Bioindicators of Arsenic Contamination.

https://arctichealth.org/en/permalink/ahliterature271254
Source
Microb Ecol. 2016 Mar 30;
Publication Type
Article
Date
Mar-30-2016
Author
Nawaf A Nasser
R Timothy Patterson
Helen M Roe
Jennifer M Galloway
Hendrik Falck
Michael J Palmer
Christopher Spence
Hamed Sanei
Andrew L Macumber
Lisa A Neville
Source
Microb Ecol. 2016 Mar 30;
Date
Mar-30-2016
Language
English
Publication Type
Article
Abstract
Arcellininids (testate amoebae) were examined from 61 surface sediment samples collected from 59 lakes in the vicinity of former gold mines, notably Giant Mine, near Yellowknife, Northwest Territories, Canada to determine their utility as bioindicators of arsenic (As), which occurs both as a byproduct of gold extraction at mines in the area and ore-bearing outcrops. Cluster analysis (Q-R-mode) and detrended correspondence analysis (DCA) reveal five arcellininid assemblages, three of which are related to varying As concentrations in the sediment samples. Redundancy analysis (RDA) showed that 14 statistically significant environmental parameters explained 57 % of the variation in faunal distribution, while partial RDA indicated that As had the greatest influence on assemblage variance (10.7 %; p??10000 ppm, min?=?16.1 ppm, n?=?32), while difflugiid dominated assemblages were prevalent in substrates with relatively low As concentrations (median?=?30.2 ppm, max?=?905.2 ppm, min?=?6.3 ppm, n?=?20). Most of the lakes with very high As levels are located downwind (N and W) of the former Giant Mine roaster stack where refractory ore was roasted and substantial quantities of As were released (as As2O3) to the atmosphere in the first decade of mining. This spatial pattern suggests that a significant proportion of the observed As, in at least these lakes, are industrially derived. The results of this study highlight the sensitivity of Arcellinina to As and confirm that the group has considerable potential for assessing the impact of As contamination on lakes.
PubMed ID
27026100 View in PubMed
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Late Holocene climatic variability in Subarctic Canada: Insights from a high-resolution lake record from the central Northwest Territories.

https://arctichealth.org/en/permalink/ahliterature292541
Source
PLoS One. 2018; 13(6):e0199872
Publication Type
Journal Article
Date
2018
Author
April S Dalton
R Timothy Patterson
Helen M Roe
Andrew L Macumber
Graeme T Swindles
Jennifer M Galloway
Jesse C Vermaire
Carley A Crann
Hendrik Falck
Author Affiliation
Ottawa-Carleton Geoscience Centre and Department of Earth Sciences, Carleton University, Ottawa, Canada.
Source
PLoS One. 2018; 13(6):e0199872
Date
2018
Language
English
Publication Type
Journal Article
Abstract
We examined late Holocene (ca. 3300 yr BP to present-day) climate variability in the central Northwest Territories (Canadian Subarctic) using a diatom and sedimentological record from Danny's Lake (63.48ºN, 112.54ºW), located 40 km southwest of the modern-day treeline. High-resolution sampling paired with a robust age model (25 radiocarbon dates) allowed for the examination of both lake hydroecological conditions (30-year intervals; diatoms) and sedimentological changes in the watershed (12-year intervals; grain size records) over the late Holocene. Time series analysis of key lake ecological indicators (diatom species Aulacoseira alpigena, Pseudostaurosira brevistriata and Achnanthidium minutissimum) and sedimentological parameters, reflective of catchment processes (coarse silt fraction), suggests significant intermittent variations in turbidity, pH and light penetration within the lake basin. In the diatom record, we observed discontinuous periodicities in the range of ca. 69, 88-100, 115-132, 141-188, 562, 750 and 900 years (>90% and >95% confidence intervals), whereas the coarse silt fraction was characterized by periodicities in the >901 and 95% confidence interval). Periodicities in the proxy data from the Danny's Lake sediment core align with changes in total solar irradiance over the past ca. 3300 yr BP and we hypothesize a link to the Suess Cycle, Gleissberg Cycle and Pacific Decadal Oscillation via occasional inland propagation of shifting air masses over the Pacific Ocean. This research represents an important baseline study of the underlying causes of climate variability in the Canadian Subarctic and provides details on the long-term climate variability that has persisted in this region through the past three thousand years.
Notes
Cites: Biol Rev Camb Philos Soc. 2015 May;90(2):522-41 PMID 24917134
Cites: Proc Natl Acad Sci U S A. 2005 Mar 22;102(12):4397-402 PMID 15738395
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Cites: Proc Natl Acad Sci U S A. 2004 Mar 23;101(12):4136-41 PMID 15016919
Cites: Sci Rep. 2014 Jan 09;4:3611 PMID 24402348
PubMed ID
29953559 View in PubMed
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Late Holocene climatic variability in Subarctic Canada: Insights from a high-resolution lake record from the central Northwest Territories.

https://arctichealth.org/en/permalink/ahliterature296859
Source
PLoS One. 2018; 13(6):e0199872
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
2018
Author
April S Dalton
R Timothy Patterson
Helen M Roe
Andrew L Macumber
Graeme T Swindles
Jennifer M Galloway
Jesse C Vermaire
Carley A Crann
Hendrik Falck
Author Affiliation
Ottawa-Carleton Geoscience Centre and Department of Earth Sciences, Carleton University, Ottawa, Canada.
Source
PLoS One. 2018; 13(6):e0199872
Date
2018
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Canada
Climate change
Diatoms
Fossils
Lakes
Abstract
We examined late Holocene (ca. 3300 yr BP to present-day) climate variability in the central Northwest Territories (Canadian Subarctic) using a diatom and sedimentological record from Danny's Lake (63.48ºN, 112.54ºW), located 40 km southwest of the modern-day treeline. High-resolution sampling paired with a robust age model (25 radiocarbon dates) allowed for the examination of both lake hydroecological conditions (30-year intervals; diatoms) and sedimentological changes in the watershed (12-year intervals; grain size records) over the late Holocene. Time series analysis of key lake ecological indicators (diatom species Aulacoseira alpigena, Pseudostaurosira brevistriata and Achnanthidium minutissimum) and sedimentological parameters, reflective of catchment processes (coarse silt fraction), suggests significant intermittent variations in turbidity, pH and light penetration within the lake basin. In the diatom record, we observed discontinuous periodicities in the range of ca. 69, 88-100, 115-132, 141-188, 562, 750 and 900 years (>90% and >95% confidence intervals), whereas the coarse silt fraction was characterized by periodicities in the >901 and 95% confidence interval). Periodicities in the proxy data from the Danny's Lake sediment core align with changes in total solar irradiance over the past ca. 3300 yr BP and we hypothesize a link to the Suess Cycle, Gleissberg Cycle and Pacific Decadal Oscillation via occasional inland propagation of shifting air masses over the Pacific Ocean. This research represents an important baseline study of the underlying causes of climate variability in the Canadian Subarctic and provides details on the long-term climate variability that has persisted in this region through the past three thousand years.
PubMed ID
29953559 View in PubMed
Less detail

Mineralogical, geospatial, and statistical methods combined to estimate geochemical background of arsenic in soils for an area impacted by legacy mining pollution.

https://arctichealth.org/en/permalink/ahliterature303593
Source
Sci Total Environ. 2021 Feb 18; 776:145926
Publication Type
Journal Article
Date
Feb-18-2021
Author
Michael J Palmer
Heather E Jamieson
Anežka Borcinová Radková
Kirsten Maitland
Jon Oliver
Hendrik Falck
Murray Richardson
Author Affiliation
North Slave Research Centre, Aurora Research Institute, Aurora College, Yellowknife X1A 2R3, Canada; Department of Geography and Environmental Studies, Carleton University, Ottawa K1S 5B6, Canada. Electronic address: mpalmer@auroracollege.nt.ca.
Source
Sci Total Environ. 2021 Feb 18; 776:145926
Date
Feb-18-2021
Language
English
Publication Type
Journal Article
Abstract
The estimation of geochemical background is complex in areas impacted by point sources of atmospheric emissions due to unknowns about pollutant dispersion, persistence of pollutants on the landscape, and natural concentrations of elements associated with parent material. This study combined mineralogical analysis with conventional statistical and geospatial methods to separate anthropogenically impacted soils from unimpacted soils in the Yellowknife area, Northwest Territories, Canada, a region that was exposed to 60 years of arsenic (As)-rich atmospheric mining emissions (1938-1999) and that hosts natural enrichments of As. High concentrations of As (up to 4700 mg kg-1) were measured in publicly accessible soils near decommissioned roaster stacks in the region and strong relationships between As and distance from the main emission sources persisted in surface soils and soils at depth in the soil profile more than 60 years after the bulk of mining emissions were released. Mineralogical analysis provided unambiguous evidence regarding the source of As minerals and highlighted that most As in surface soils within 15 km of Yellowknife is hosted as anthropogenic arsenic trioxide (As2O3), produced by roaster stack emissions. Statistical protocols for the estimation of geochemical background were applied to an existing database of till geochemistry (N = 1490) after removing samples from mining impacted areas. Results suggested geochemical background for the region is 0.25-15 mg kg-1 As, comparable to global averages, with upper thresholds elevated in volcanic units (30 mg kg-1 As) that often host sulfide mineralization in greenstone belts in the region.
PubMed ID
33652309 View in PubMed
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Organic matter control on the distribution of arsenic in lake sediments impacted by ~65years of gold ore processing in subarctic Canada.

https://arctichealth.org/en/permalink/ahliterature286986
Source
Sci Total Environ. 2017 Oct 27;
Publication Type
Article
Date
Oct-27-2017
Author
Jennifer M Galloway
Graeme T Swindles
Heather E Jamieson
Michael Palmer
Michael B Parsons
Hamed Sanei
Andrew L Macumber
R. Timothy Patterson
Hendrik Falck
Source
Sci Total Environ. 2017 Oct 27;
Date
Oct-27-2017
Language
English
Publication Type
Article
Abstract
Climate change is profoundly affecting seasonality, biological productivity, and hydrology in high northern latitudes. In sensitive subarctic environments exploitation of mineral resources led to contamination and it is not known how cumulative effects of resource extraction and climate warming will impact ecosystems. Gold mines near Yellowknife, Northwest Territories, subarctic Canada, operated from 1938 to 2004 and released >20,000t of arsenic trioxide (As2O3) to the environment through stack emissions. This release resulted in elevated arsenic concentrations in lake surface waters and sediments relative to Canadian drinking water standards and guidelines for the protection of aquatic life. A meta-analytical approach is used to better understand controls on As distribution in lake sediments within a 30-km radius of historic mineral processing activities. Arsenic concentrations in the near-surface sediments range from 5mg·kg(-1) to over 10,000mg·kg(-1) (median 81mg·kg(-1); n=105). Distance and direction from the historic roaster stack are significantly (p
PubMed ID
29111252 View in PubMed
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What killed Frame Lake? A precautionary tale for urban planners.

https://arctichealth.org/en/permalink/ahliterature292436
Source
PeerJ. 2018; 6:e4850
Publication Type
Journal Article
Date
2018
Author
Melody J Gavel
R Timothy Patterson
Nawaf A Nasser
Jennifer M Galloway
Bruce W Hanna
Peter A Cott
Helen M Roe
Hendrik Falck
Author Affiliation
Department of Earth Sciences and Ottawa-Carleton Geoscience Centre, Carleton University, Ottawa, Ontario, Canada.
Source
PeerJ. 2018; 6:e4850
Date
2018
Language
English
Publication Type
Journal Article
Abstract
Frame Lake, located within the city of Yellowknife, Northwest Territories, Canada, has been identified as requiring significant remediation due to its steadily declining water quality and inability to support fish by the 1970s. Former gold mining operations and urbanization around the lake have been suspected as probable causes for the decline in water quality. While these land-use activities are well documented, little information is available regarding their impact on the lake itself. For this reason, Arcellinida, a group of shelled protozoans known to be reliable bioindicators of land-use change, were used to develop a hydroecological history of the lake. The purpose of this study was to use Arcellinida to: (1) document the contamination history of the lake, particularly related to arsenic (As) associated with aerial deposition from mine roaster stacks; (2) track the progress of water quality deterioration in Frame Lake related to mining, urbanization and other activities; and (3) identify any evidence of natural remediation within the lake. Arcellinida assemblages were assessed at 1-cm intervals through the upper 30 cm of a freeze core obtained from Frame Lake. The assemblages were statistically compared to geochemical and loss-on-ignition results from the core to document the contamination and degradation of conditions in the lake. The chronology of limnological changes recorded in the lake sediments were derived from 210Pb, 14C dating and known stratigraphic events. The progress of urbanization near the lake was tracked using aerial photography. Using Spearman correlations, the five most significant environmental variables impacting Arcellinida distribution were identified as minerogenics, organics, As, iron and mercury (p 7,000 years before present; the As Contamination Assemblage (ACA), ranging from 7-16 cm, deposited after ~1962 when sedimentation began in the lake again following a long hiatus that spanned to the early Holocene; and the Eutrophication Assemblage (EA), ranging from 1-6 cm, comprised of sediments deposited after 1990 following the cessation of As and other metal contaminations. The EA developed in response to nutrient-rich waters entering the lake derived from the urbanization of the lake catchment and a reduction in lake circulation associated with the development at the lake outlet of a major road, later replaced by a causeway with rarely open sluiceways. The eutrophic condition currently charactering the lake-as evidenced by a population explosion of eutrophication indicator taxa Cucurbitella tricuspis-likely led to a massive increase in macrophyte growth and winter fish-kills. This ecological shift ultimately led to a system dominated by Hirudinea (leeches) and cessation of the lake as a recreational area.
Notes
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PubMed ID
29915687 View in PubMed
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8 records – page 1 of 1.