PEARL  Paleoecological Environmental Assessment and Research Laboratory

Department of Biology, Queen's University, Kingston ON, Canada, K7L 3N6

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Climate-driven regime shifts in the biological communities of arctic lakes
| Press release Queen's University | Pearl Home | PDF of article | Original Douglas et al 1994 |  Data sources |

 Arctic Lake Images Click on an image below to open a higher resolution version.




Rock Basin Lake, Baird Inlet (east-central Ellesmere Island, Nunavut, Canadian High Arctic) was the site of the first detailed paleolimnological study from the circumpolar region, which used diatom and chrysophyte microfossils to track past climatic change. 

As climatic change is predicted to be more pronounced in arctic regions, lakes in northern locations are especially sensitive.  






Photograph: John P. Smol, Queen's University, August 1987




A typical lake from north-central Ellesmere Island, Nunavut, Canadian High Arctic. The central float of ice may persist throughout the summer during cool years in some lakes.





Photograph: Bronwyn Keatley, Queen's University, July 2003





A subarctic lake from northern Québec (Nunavik). 






Photograph:  Reinhard Pienitz, Université Laval, August 2002


Using a Glew Gravity Corer (developed at PEARL) to collect a vertical sample of lake sediments which can be extruded into slices for discrete samples.





Photograph: J.P. Smol










A mini-Glew gravity corer (developed by John Glew, PEARL) was used to collect a sediment core from a remote subarctic lake, Northwest Territories, Canada.  Here the sample was retrieved off the pontoons of a helicopter. 






Photograph: Kathleen Rühland, Queen's University






Once the sediment core has been obtained, it is sectioned into discrete layers.  Each sedimentary layer contains biological microfossils that are representative of the environmental conditions present during the time at which they lived in the lake. 




 Photograph:  Marianne Douglas, University of Toronto, 2003







  Diploneis sp.    Photograph: Daniel T. Selbie, Queen's University


Diatoms (siliceous algae) are abundant and diverse components of the biota of most lakes, ponds, and rivers, and preserve well in lake sediments.  Different species are characteristic of different types of environments and the abundance of different species in the lake sediments can be used to determine past environmental conditions.  



Navicula sp.  Photograph: Kathleen Rühland, Queen's University




Chitinous head capsules of larval chironomids (non-biting midges, a type of insect) represent another type of biological indicator preserved in lake sediments.







Sergentia  sp. Photograph: Jon Sweetman, Queen's University





Cladoceran zooplankton, such as the chydorids, are also well-preserved in lake sediments, as their carapaces are made of chitin.






Chydorus sp. Photograph: Jon Sweetman, Queen's University


PLEASE NOTE: A PDF copy of the study can be obtained from the Proceedings of the National Academy of Sciences, or contact Dr. John Smol at for a copy. High resolution images are available upon request.

Contact Information for authors:

John Smol


Tel: +1 613-533-6147

Alexander Wolfe


Tel: (+47): 79 02 33 23


John Birks


Tel: (+47) 55 583350


Marianne Douglas


Tel: +1 416-978-3709


Vivienne J. Jones

Tel: +44 (0)20 7679 5558


Atte Korhola


Tel: +358-9-191 57 840


Reinhard Pienitz


Tel: +1 (418) 656 2131 ext. 7006


Kathleen Ruhland


Tel: +1 613-533-6000 ext. 77337


Sanna Sorvari


Tel: +358 9 191 57894


Dermot Antoniades



Steve Brooks



Marie-Andrée Fallu



Mike Hughes


Bronwyn Keatley


Tamsin Laing



Neal Michelutti



Larisa Nazarova



Marjut Nyman



Andrew Paterson



Bianca Perren



Roberto Quinlan



Milla Rautio



Émilie Saulnier-Talbot



Susanna Siitonen



Nadia Solovieva


Jan Weckström