Skip header and navigation

7 records – page 1 of 1.

Characterizing baseline concentrations, proportions, and processes controlling deposition of river-transported bitumen-associated polycyclic aromatic compounds at a floodplain lake (Slave River Delta, Northwest Territories, Canada).

https://arctichealth.org/en/permalink/ahliterature271644
Source
Environ Monit Assess. 2016 May;188(5):282
Publication Type
Article
Date
May-2016
Author
Matthew C Elmes
Johan A Wiklund
Stacey R Van Opstal
Brent B Wolfe
Roland I Hall
Source
Environ Monit Assess. 2016 May;188(5):282
Date
May-2016
Language
English
Publication Type
Article
Abstract
Inadequate knowledge of baseline conditions challenges ability for monitoring programs to detect pollution in rivers, especially where there are natural sources of contaminants. Here, we use paleolimnological data from a flood-prone lake ("SD2", informal name) in the Slave River Delta (SRD, Canada), ~500 km downstream of the Alberta oil sands development and the bitumen-rich McMurray Formation to identify baseline concentrations and proportions of "river-transported bitumen-associated indicator polycyclic aromatic compounds" (indicator PACs; Hall et al. 2012) and processes responsible for their deposition. Results show that indicator PACs are deposited in SD2 by Slave River floodwaters in concentrations that are 45 % lower than those in sediments of "PAD31compounds", a lake upstream in the Athabasca Delta that receives Athabasca River floodwaters. Lower concentrations at SD2 are likely a consequence of sediment retention upstream as well as dilution by sediment influx from the Peace River. In addition, relations with organic matter content reveal that flood events dilute concentrations of indicator PACs in SD2 because the lake receives high-energy floods and the lake sediments are predominantly inorganic. This contrasts with PAD31 where floodwaters increase indicator PAC concentrations in the lake sediments, and concentrations are diluted during low flood influence intervals due to increased deposition of lacustrine organic matter. Results also show no significant differences in concentrations and proportions of indicator PACs between pre- (1967) and post- (1980s and 1990s) oil sands development high flood influence intervals (t = 1.188, P = 0.279, d.f. = 6.136), signifying that they are delivered to the SRD by natural processes. Although we cannot assess potential changes in indicator PACs during the past decade, baseline concentrations and proportions can be used to enhance ongoing monitoring efforts.
Notes
Cites: Proc Natl Acad Sci U S A. 2009 Dec 29;106(52):22346-5119995964
Cites: J Environ Qual. 2009 Jul-Aug;38(4):1349-6219465710
Cites: Environ Pollut. 2004 Dec;132(3):413-2615325457
Cites: Sci Total Environ. 2016 Feb 15;544:811-2326688053
Cites: Environ Sci Technol. 2015 Aug 4;49(15):9056-6326115178
Cites: PLoS One. 2012;7(9):e4608923049946
Cites: Sci Total Environ. 2012 Sep 1;433:379-8222819889
Cites: Proc Natl Acad Sci U S A. 2010 Sep 14;107(37):16178-8320805486
Cites: Nature. 2010 Nov 25;468(7323):499-50121107404
PubMed ID
27071660 View in PubMed
Less detail

Distribution and diversity of diatom assemblages in surficial sediments of shallow lakes in Wapusk National Park (Manitoba, Canada) region of the Hudson Bay Lowlands.

https://arctichealth.org/en/permalink/ahliterature274198
Source
Ecol Evol. 2016 Jul;6(13):4526-40
Publication Type
Article
Date
Jul-2016
Author
Olivier Jacques
Frédéric Bouchard
Lauren A MacDonald
Roland I Hall
Brent B Wolfe
Reinhard Pienitz
Source
Ecol Evol. 2016 Jul;6(13):4526-40
Date
Jul-2016
Language
English
Publication Type
Article
Abstract
The hydrology of shallow lakes (and ponds) located in the western Hudson Bay Lowlands (HBL) is sensitive to climate warming and associated permafrost thaw. However, their biological characteristics are poorly known, which hampers effective aquatic ecosystem monitoring. Located in northern Manitoba along the southwestern coast of Hudson Bay, Wapusk National Park (WNP) encompasses numerous shallow lakes representative of the subarctic zone. We analyzed the distribution and diversity of diatom (microscopic algae; class Bacillariophyceae) assemblages in surficial sediments of 33 lakes located in three different ecozones spanning a vegetation gradient, from NE to SW: the Coastal Fen (CF), the Interior Peat Plateau (IPP), and the Boreal Spruce Forest (BSF). We found significant differences (P 
PubMed ID
27386094 View in PubMed
Less detail

Hydrologic monitoring tools for freshwater municipal planning in the Arctic: the case of Iqaluit, Nunavut, Canada.

https://arctichealth.org/en/permalink/ahliterature283129
Source
Environ Sci Pollut Res Int. 2017 Jun 06;
Publication Type
Article
Date
Jun-06-2017
Author
Michael Bakaic
Andrew Scott Medeiros
Jessica F Peters
Brent B Wolfe
Source
Environ Sci Pollut Res Int. 2017 Jun 06;
Date
Jun-06-2017
Language
English
Publication Type
Article
Abstract
Freshwater and the services it provides are vital to both natural ecosystems and human needs; however, extreme climates and their influence on freshwater availability can be challenging for municipal planners and engineers to manage these resources effectively. In Arctic Canada, financial and human capital limitations have left a legacy of freshwater systems that underserve current communities and may be inadequate in the near future under a warming climate, growing population, and increasing demand. We address this challenge to community water resource planning by applying several novel water supply forecasting methods to evaluate the Apex River as an alternative freshwater source for Iqaluit, Nunavut (Canada). Surveys of water isotope composition of the Apex River and tributaries indicated that rainfall is the main source of water replenishment. This information was utilized to calibrate a water resource assessment that considered climate forecasting scenarios and their influence on supply, and alternative scenarios for freshwater management to better adapt to a changing climate. We found that under current climate and demand conditions, the freshwater supply of Iqaluit would be in a perpetual state of drawdown by 2024. Analysis of current infrastructure proposals revealed significant deficiencies in the supply extensions proposed whereby the Apex replenishment pipeline would only provide a 2-year extension to current municipal supply. Our heuristic supply forecast methods allowed for several alternative supply strategies to be rapidly evaluated, which will aid the community planning process by specifically quantifying the service life of the city's current and future primary water supply.
PubMed ID
28589278 View in PubMed
Less detail

Hydrologic monitoring tools for freshwater municipal planning in the Arctic: the case of Iqaluit, Nunavut, Canada.

https://arctichealth.org/en/permalink/ahliterature297764
Source
Environ Sci Pollut Res Int. 2018 Nov; 25(33):32913-32925
Publication Type
Journal Article
Date
Nov-2018
Author
Michael Bakaic
Andrew Scott Medeiros
Jessica F Peters
Brent B Wolfe
Author Affiliation
Department of Environmental Studies, York University, Toronto, ON, Canada.
Source
Environ Sci Pollut Res Int. 2018 Nov; 25(33):32913-32925
Date
Nov-2018
Language
English
Publication Type
Journal Article
Keywords
Climate
Climate change
Environmental monitoring
Fresh Water - analysis
Humans
Hydrology - methods
Nunavut
Planning Techniques
Rain
Rivers - chemistry
Seasons
Water supply
Abstract
Freshwater and the services it provides are vital to both natural ecosystems and human needs; however, extreme climates and their influence on freshwater availability can be challenging for municipal planners and engineers to manage these resources effectively. In Arctic Canada, financial and human capital limitations have left a legacy of freshwater systems that underserve current communities and may be inadequate in the near future under a warming climate, growing population, and increasing demand. We address this challenge to community water resource planning by applying several novel water supply forecasting methods to evaluate the Apex River as an alternative freshwater source for Iqaluit, Nunavut (Canada). Surveys of water isotope composition of the Apex River and tributaries indicated that rainfall is the main source of water replenishment. This information was utilized to calibrate a water resource assessment that considered climate forecasting scenarios and their influence on supply, and alternative scenarios for freshwater management to better adapt to a changing climate. We found that under current climate and demand conditions, the freshwater supply of Iqaluit would be in a perpetual state of drawdown by 2024. Analysis of current infrastructure proposals revealed significant deficiencies in the supply extensions proposed whereby the Apex replenishment pipeline would only provide a 2-year extension to current municipal supply. Our heuristic supply forecast methods allowed for several alternative supply strategies to be rapidly evaluated, which will aid the community planning process by specifically quantifying the service life of the city's current and future primary water supply.
PubMed ID
28589278 View in PubMed
Less detail

Limnological regime shifts caused by climate warming and Lesser Snow Goose population expansion in the western Hudson Bay Lowlands (Manitoba, Canada).

https://arctichealth.org/en/permalink/ahliterature261023
Source
Ecol Evol. 2015 Feb;5(4):921-39
Publication Type
Article
Date
Feb-2015
Author
Lauren A MacDonald
Nicole Farquharson
Gillian Merritt
Sam Fooks
Andrew S Medeiros
Roland I Hall
Brent B Wolfe
Merrin L Macrae
Jon N Sweetman
Source
Ecol Evol. 2015 Feb;5(4):921-39
Date
Feb-2015
Language
English
Publication Type
Article
Abstract
Shallow lakes are dominant features in subarctic and Arctic landscapes and are responsive to multiple stressors, which can lead to rapid changes in limnological regimes with consequences for aquatic resources. We address this theme in the coastal tundra region of Wapusk National Park, western Hudson Bay Lowlands (Canada), where climate has warmed during the past century and the Lesser Snow Goose (LSG; Chen caerulescens caerulescens) population has grown rapidly during the past ?40 years. Integration of limnological and paleolimnological analyses documents profound responses of productivity, nutrient cycling, and aquatic habitat to warming at three ponds ("WAP 12", "WAP 20", and "WAP 21?), and to LSG disturbance at the two ponds located in an active nesting area (WAP 20, WAP 21). Based on multiparameter analysis of (210)Pb-dated sediment records from all three ponds, a regime shift occurred between 1875 and 1900 CE marked by a transition from low productivity, turbid, and nutrient-poor conditions of the Little Ice Age to conditions of higher productivity, lower nitrogen availability, and the development of benthic biofilm habitat as a result of climate warming. Beginning in the mid-1970s, sediment records from WAP 20 and WAP 21 reveal a second regime shift characterized by accelerated productivity and increased nitrogen availability. Coupled with 3 years of limnological data, results suggest that increased productivity at WAP 20 and WAP 21 led to atmospheric CO2 invasion to meet algal photosynthetic demand. This limnological regime shift is attributed to an increase in the supply of catchment-derived nutrients from the arrival of LSG and their subsequent disturbance to the landscape. Collectively, findings discriminate the consequences of warming and LSG disturbance on tundra ponds from which we identify a suite of sensitive limnological and paleolimnological measures that can be utilized to inform aquatic ecosystem monitoring.
PubMed ID
25750718 View in PubMed
Less detail

Paleolimnological assessment of riverine and atmospheric pathways and sources of metal deposition at a floodplain lake (Slave River Delta, Northwest Territories, Canada).

https://arctichealth.org/en/permalink/ahliterature268651
Source
Sci Total Environ. 2015 Dec 11;544:811-823
Publication Type
Article
Date
Dec-11-2015
Author
Lauren A MacDonald
Johan A Wiklund
Matthew C Elmes
Brent B Wolfe
Roland I Hall
Source
Sci Total Environ. 2015 Dec 11;544:811-823
Date
Dec-11-2015
Language
English
Publication Type
Article
Abstract
Growth of natural resource development in northern Canada has raised concerns about the effects on downstream aquatic ecosystems, but insufficient knowledge of pre-industrial baseline conditions continues to undermine ability of monitoring programs to distinguish industrial-derived contaminants from those supplied by natural processes. Here, we apply a novel paleolimnological approach to define pre-industrial baseline concentrations of 13 priority pollutant metals and vanadium and assess temporal changes, pathways and sources of these metals at a flood-prone lake (SD2) in the Slave River Delta (NWT, Canada) located ~500km north of Alberta's oil sands development and ~140km south of a former gold mine at Yellowknife, NWT. Results identify that metal concentrations, normalized to lithium concentration, are not elevated in sediments deposited during intervals of high flood influence or low flood influence since onset of oil sands development (post-1967) relative to the 1920-1967 baseline established at SD2. When compared to a previously defined baseline for the upstream Athabasca River, several metal-Li relations (Cd, Cr, Ni, Zn, V) in post-1967 sediments delivered by floodwaters appear to plot along a different trajectory, suggesting that the Peace and Slave River watersheds are important natural sources of metal deposition at the Slave River Delta. However, analysis revealed unusually high concentrations of As deposited during the 1950s, an interval of very low flood influence at SD2, which corresponded closely with emission history of the Giant Mine gold smelter indicating a legacy of far-field atmospheric pollution. Our study demonstrates the potential for paleolimnological characterization of baseline conditions and detection of pollution from multiple pathways in floodplain ecosystems, but that knowledge of paleohydrological conditions is essential for interpretation of contaminant profiles.
PubMed ID
26688053 View in PubMed
Less detail

Source apportionment of background PAHs in the Peace-Athabasca Delta (Alberta, Canada) using molecular level radiocarbon analysis.

https://arctichealth.org/en/permalink/ahliterature264200
Source
Environ Sci Technol. 2015 Jun 26;
Publication Type
Article
Date
Jun-26-2015
Author
Josué Jules Jautzy
Jason M E Ahad
Roland Isham Hall
Johan A Wiklund
Brent B Wolfe
Charles Gobeil
Martine M Savard
Source
Environ Sci Technol. 2015 Jun 26;
Date
Jun-26-2015
Language
English
Publication Type
Article
Abstract
The downstream accumulation of polycyclic aromatic hydrocarbons (PAHs) in the Peace-Athabasca Delta (PAD), an ecologically important landscape, is a key issue of concern given the rapid development of the oil sands industry in Northern Alberta, Canada. In addition to PAHs derived from industrial activity (i.e., oil sands mining) within the Athabasca watershed, however, forest fires and erosion of fossil fuel deposits within both the Athabasca and Peace watersheds are two potentially important natural sources of PAHs delivered to the PAD. Consequently, evaluating the environmental impact of mining activities requires a quantitative understanding of natural, background PAHs. Here, we utilize molecular-level natural-abundance radiocarbon measurements on an amalgamated sediment record from a Peace River flood-susceptible oxbow lake in the northern Peace sector of the PAD to quantitatively discriminate sources of naturally occurring alkylated PAHs (fossil and modern biomass). A radiocarbon mass balance quantified a predominantly natural petrogenic source (93% petrogenic, 7% forest fire) for alkylated PAHs during the past ~50 years. Additionally, a significant petrogenic component determined for retene, a compound usually considered a biomarker for softwood combustion, suggests that its use as a unique forest fire indicator may not be suitable in PAD sediments receiving Peace watershed-derived fluvial inputs.
PubMed ID
26115178 View in PubMed
Less detail

7 records – page 1 of 1.