Project Description by Reinhard Pienitz and Warwick F. Vincent
Project theme: Paleoclimates and limnology of the Foxe Basin and surrounding regions (Nunavut)
Background
Evidence of rapid climate change at northern latitudes has focused research efforts on arctic and subarctic
environments. Due to possible feedback mechanisms, such as snow and sea ice extent (albedo changes), these
regions are particularly sensitive to global warming. Many studies have already shown that some arctic areas have
undergone major modifications of their annual thermal budget during the second half of the last century. They
specifically showed an increase of surface air temperatures during summer, and a drastic reduction of winter sea ice
cover thickness and summer extent. On the other hand, regions surrounding the Foxe Basin, the Hudson Bay, and the
Hudson Strait are so far only slightly affected by such global warming effects, showing only slight increases (<
0.5°C) in mean annual air temperature over the last 50 years and even a cooling during the winter season. These
contrasting climate scenarios revealed the necessity to extend our knowledge of past and present environmental
conditions to this important transition region between the High Arctic and Low Arctic in order to be able to refine
our ability to model past, present and future environmental changes in the Canadian North.
Research problem
The main purpose of our research is to reconstruct past climates using sediment records from a series of lakes in the
Foxe Basin region. Using biological and physical data extracted from these records, we will determine the potential
responses of northern lakes and their watersheds to past climate changes, in order to predict future impacts of climate
change. We will couple this research to sampling and analyses of the modern-day limnological properties of
freshwater ecosystems in this little studied transition region.
Overall research objectives
Methods
Lakes and ponds are a major feature of the arctic landscape (Vincent & Laybourn-Parry 2008), and these contain
sediment archives from which biological, physical and chemical proxies can be extracted to reconstruct climate and
environmental changes through time (reviewed in Pienitz et al. 2004). To explore the past natural environmental
climate fluctuations of the regions of interest, we are planning on collecting sediment cores from a series of lakes
located in the vicinity of Koukdjuak, Nikko Island (Lake Nettilling; 66°35’42.10”N, 71°31’23.87”W) (see Annexe 1
for map of study area). We will focus our sampling not only on large postglacial lakes but also on “thermokarst
lakes”. Resulting from a partial and local melting of the permafrost in subarctic regions, these lakes are believed to
be responsible of releasing high amount of greenhouse gases (CO2 and CH4), initially trapped in the organic richpermafrost. The faunal (chironomids) and floral (diatoms) fossil assemblages within each sedimentary sequence will
be analyzed, along with sedimentological and geochemical analyses (X-ray fluorescence, grain-size, organic content
(% of carbon and nitrogen)) to quantitatively track long-term environmental changes during the postglacial period
and/or since the creation of these “thermokarst lakes”. The combination of both biological and geochemical
indicators remains uncommon but provides a deeper understanding of the environmental parameters that determine
the functioning of aquatic ecosystems. Reconstruction of past air and water temperatures will be accomplished using
newly developed chironomid-based inference models (Larocque et al. 2006). Past levels of trophic state (nutrients
like P and N) will be inferred using algal (diatom) fossils along with isotopic (15N) and biogenic silica (BSi)
analyses. Sediment and water samples from each study site will also be collected for our collaborators on studies of
northern lake contaminants (Dr. Derek Muir, Water Science and Technology Directorate, Environment Canada;
Burlington, Ontario). Also, as part of CEN’s SILA network, a new automated weather station will be installed on
Nikko Island.
The fieldwork planned for the summer of 2010 has six objectives (see below for progress report of the 2004-2009
field seasons):
1) Extend our limnological survey over a region that have so far never been extensively studied and where
important data gaps exist with respect to the modeling of past climates;
2) Undertake a survey of the thermokarst lakes which we have identified in abundance from satellite imagery;
3) Using a small inflatable boat with paddles, we will use a simple echosounder (“fish finder”) to explore the
depth characteristics of the selected lakes. Lake sediments will be retrieved from the deepest part of the
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basin using simple coring devices (tubes 6.5 to 9.0 cm in diameter) that penetrate sediments by their own
weight (= gravity corers);
4) For each lake, we will take small water samples (ca. 1 liter) from the upper water column for extended
chemical analyses by Environment Canada (Burlington, Ontario) laboratories;
5) Install a permanent automated weather station for CEN’s SILA network
6) Make contacts with and inform local authorities about our research activities to ensure that we have the full
permission to take samples from the lakes within the study area.
The proposed sampling activities will be logistically challenging because of the remoteness of the study region,
which also explains the lack of environmental information from this vast area at the centre of the eastern Canadian
Arctic. The short survey of this region carried out during our 2009 mission revealed that overnight stays at or near
the CWS station on Nikko Island are necessary to complete the planned fieldwork. As discussed with Dr. Jim
Leafloor (CWS Winnipeg, Manitoba) during a recent phone call, we have the permission to use the CWS camp on
Nikko Island, which would provide a perfect logistical base to conduct our research. We will access the study
regions via helicopter and Twin-Otter support provided by PCSP. Our research team and gear will be transported
from Iqaluit to the camp on July 30 and we will return from the area on August 03. Two of our team members (Denis
Sarrazin and Warwick Vincent) will install a new CEN weather station at this site and will conduct limnological
sampling. This region is currently a major gap in the CEN Network of climate and aquatic observation sites, and the
Nunavut Research Institute has requested that CEN become more active in this part of Nunavut.
Graduate student involvement
To assure the success of this long-term arctic paleoenvironmental monitoring program, one post-doctoral researcher
(Dr. Nicolas Rolland), one graduate student (TBA) and at least one undergraduate student (Anne Beaudouin) will be
involved and trained in all aspects of our research. This includes the biostratigraphic and sedimentological analyses,
the limnological measurements (water column profiling and sampling), as well as the sampling of short and long
sediment cores from the sites selected for the paleolimnological analyses.
Progress report of results achieved to date
The fieldwork planned for the summer of 2010 will extend our successful activities initiated in 2004 on Southampton
Island, and more recently in August 2009 on the Melville Peninsula and Baffin Island with the help of PCSP who
kindly provided helicopter support to meet our logistics needs to sample lake sediments. The 2009 fieldwork allowed
us to collect sediment cores and water samples from eight lakes located near the regions of Steensby Inlet (northern
Baffin Island), northern Melville Peninsula, and north of the Nettilling lake/Taverner Bay area. All the lakes were
carefully chosen based on their potential to provide the longest-possible sediment records since the last deglaciation
in this region, which led us to high altitude headwater lakes (> 200 m a.s.l.). For each lake, long sediment cores (ca.
80 – 100 cm) were collected using a handheld percussion corer, and kept intact inside their respective sampling tube
for transportation to our laboratory facilities in Quebec City. Non-destructive geochemical analyses were conducted
with a Geotek Multi-Sensor Core Logger (MSCL) at the Sedimentary Paleomagnetism Laboratory of ISMER
(Rimouski) and an ITRAXTM core scanner at the GIRAS Laboratory of INRS-ETE (Québec). In addition to
providing major chemical element profiles along each core with x-ray fluorescence (XRF), these analyses produced
high-definition optical images of each core with diffuse spectral reflectance (spectrophotometer), bulk density,
radiographic (x-ray), magnetic susceptibility and P-wave profiles. Destructive analyses then followed, each core was
sliced into 0.5 cm intervals, and sediments were prepared for subsequent paleolimnological analyses including the
description of the fossil phytoplankton (diatom) and zoobenthos (chironomid) assemblages (analyses ongoing).
Geochemical analyses of grain-size and for organic composition and radioisotopic dating were also performed. When
available (probably by mid-2010), the full set of results will be submitted for publication in peer-reviewed journals.
Preliminary results have already extended our knowledge of past climate variability in the region surrounding the
Foxe Basin, and will be presented at the international Arctic Change conference as part of our scientific participation
within ArcticNet and the International Polar Year (IPY). The results of previous fieldwork activities on Southampton
Island have already been published in various journals (e.g. Rolland et al. 2008) and presented worldwide in a series
of symposia and workshops. All our results have also been made available to the Nunavut Research Institute and the
local communities within each study region, besides having led to the graduation of several graduate students.
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References
Larocque, I., Pienitz, R. & Rolland, N. 2006. Factors influencing the distribution of chironomids in lakes distributed
along a latitudinal gradient in northwestern Québec, Canada. Can. J. Fish. Aquat. Sci. 63: 1286-1297.
Pienitz, R., Douglas, M.S.V. & Smol, J.P. (eds.) 2004. Long-Term Environmental Change in Arctic and Antarctic
Lakes. Developments in Paleoenvironmental Research vol. 8, Springer Publishers, 562 pp. ISBN 1-4020-2125-9.
Rolland, N., Larocque, I., Francus, P., Pienitz, R. & Laperrière, L. 2008. Holocene climate inferred from biological
(Diptera: Chironomidae) analyses in a Southampton Island (Nunavut, Canada) lake. The Holocene 18: 229-241.
Vincent, W.F. and Laybourn-Parry, J. (eds). 2008. Polar Lakes and Rivers – Limnology of Arctic and Antarctic
Aquatic Ecosystems. Oxford University Press, UNEP International Polar Year Books Series, United Kingdom,
327pp.
Recent peer-reviewed publications by Warwick F. Vincent (*students and postdocs)
Vincent, W.F. and Laybourn-Parry, J. (eds). 2008. Polar Lakes and Rivers – Limnology of Arctic and Antarctic
Aquatic Ecosystems. Oxford University Press, UNEP International Polar Year Books Series, United Kingdom,
327pp.
Vincent, W.F. and Pedrós-Alió, C. (eds). 2008. Sea Ice and Life in a Riverinfluenced Arctic Shelf Ecosystem.
Journal of Marine Systems, Elsevier, The Netherlands, (special issue) 74 (3/4): 739-1024.
Jungblut*, A., Lovejoy, C. & Vincent, W.F. 2009. Global distribution of cyanobacterial ecotypes in the cold
biosphere. The ISME Journal (in press).
Williamson, C.E., Saros, J.E., Vincent, W.F. and Smol, J.P. 2009. Lakes and reservoirs as sentinels, integrators, and
regulators of climate change. Limnology and Oceanography (in press).
Laurion, I., Vincent, W.F., Retamal*, L., Dupont*, C., Francus, P., MacIntyre, S. and Pienitz, R. 2009. Variability in
greenhouse gas emissions from permafrost thaw ponds. Limnology and Oceanography (in press).
Rautio, M., Bonilla*, S. & Vincent, W.F. 2009. UV photoprotectants in arctic zooplankton. Aquatic Biology (in
press).
Muir, D.C.G., Wang, X., Yang, F., Nguyen, N., Jackson, T.A., Evans, M.S., Douglas, M., Kock, G., Lamoureux, S.,
Pienitz, R., Smol, J.P., Vincent, W.F. & Dastoor, A. 2009. Spatial trends and historical deposition of mercury in
eastern and northern Canada inferred from lake sediment cores. Environmental Science and Technology 43: 48024809.
Matsuoka*, A., Larouche, P., Poulin, M., Vincent, W.F. & Hattori, H. 2009. Phytoplankton community adaptation to
changing light levels in the southern Beaufort Sea, Canadian Arctic, Estuarine, Coastal and Shelf Sciences 82: 537546.
Vincent, W.F., Whyte, L.G., Lovejoy, C., Greer, C.W., Laurion, I., Suttle, C.A., Corbeil, J. & Mueller*, D.R. 2009.
Arctic microbial ecosystems and impacts of extreme warming during the International Polar Year. Polar Science,
doi:10.1016/j.polar.2009.05.004
Tomkins*, J.D., Lamoureux, S.F. Antoniades*, D., & Vincent, W.F. 2009. Sedimentology of perennial ice-covered,
meromictic Lake A, Ellesmere Island, at the northern extreme of Canada. Canadian Journal of Earth Sciences 46:
83–100.
Mueller*, D.R., Van Hove*, P., Antoniades*, D., Jeffries, M.O. & Vincent, W.F. 2009. High Arctic lakes as sentinel
ecosystems: cascading regime shifts in climate, ice-cover and mixing. Limnology and Oceanography (in press).
Terrado*, R., Vincent, W.F. & Lovejoy, C. 2009. Mesopelagic protists: diversity and succession in a coastal Arctic
ecosystem. Aquatic Microbial Ecology 56: 25-40.
Antoniades*, D., Veillette*, J., Martineau, M-J., Belzile*, C., Tomkins*, J. Pienitz, R. Lamoureux, S. & Vincent,
W.F. 2009. Bacterial dominance of phototrophic communities in a High Arctic lake and its implications for
paleoclimate analysis. Polar Science (in press).
Osburn, C. Retamal*, L. & Vincent W.F. 2009. Photoreactivity of chromophoric dissolved organic matter
transported by the Mackenzie River to the Beaufort Sea. Marine Chemistry 115: 10-20.
Xie, H., Bélanger*, S. Demers, S., Vincent, W.F. & Papakyriakou, T.N. 2009. Photobiogeochemical cycling of
carbon monoxide in the southeastern Beaufort Sea in spring and autumn. Limnology and Oceanography 54: 234-249.
Pouliot*, J., Galand*, P.E., Lovejoy, C. & Vincent, W.F. 2009. Vertical structure of archaeal communities and the
distribution of ammonia monooxygenase A gene variants in two high Arctic lakes. Environmental Microbiology,
Environmental Microbiology 11: 687–699, doi:10.1111/j.1462-2920.2008.01846.x
Tomkins*, J.D., Lamoureux, S.F., Antoniades D. & Vincent W.F. 2009. Sedimentary pellets as an ice cover proxy in
a High Arctic ice-covered lake. Journal of Paleolimnology 41: 225–242.
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Veillette*, J., Mueller*, D.R., Antoniades*, D. & Vincent, W.F. 2008. Arctic epishelf lakes as sentinel ecosystems:
past, present and future. Journal of Geophysical Research-Biogeosciences 113, G04014, doi:10.1029/2008JG000730.
Garneau*, M-E, Vincent, W.F., Terrado*, R. & Lovejoy, C. 2008. Importance of particle-associated bacterial
heterotrophy in a coastal Arctic ecosystem. Journal of Marine Systems 75: 185-197.
Bonilla*, S., Rautio*, M. & Vincent, W.F. 2009. Phytoplankton and phytobenthos pigment strategies: Implications
for algal survival in the changing Arctic. Polar Biology doi: 10.1007/s00300-009-0626-1
Vincent, W.F. 2009. Effects of climate change on lakes. In: Likens, G.E. (ed.) Encyclopedia of Inland Waters vol. 3,
Elsevier, Oxford U.K., pp 55-60.
Vincent, W.F. 2009. Cyanobacteria. In: Likens, G.E. (ed.) Encyclopedia of Inland Waters vol. 3, Elsevier, Oxford
U.K., pp 226-232.
Plus 61 others from 2004-2009 (details at www.cen.ulaval.ca/warwickvincent/publications.html)
Annexe 1: Map of Study area projected for 2010 and location of previous study sites already sampled.
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