About

To fill the important knowledge gap on the biogeography and autecology of northern circumpolar diatoms, the maximum available information must be collected. Assembling regional data makes it possible to draw ecological and environmental conclusions at a larger geographical scale. The Circumpolar Diatom Database project aims to respond to these needs. The CDD project was initiated in 1997 in the Laboratoire de Paléoécologie Aquatique (LPA - Aquatic Paleoecology Laboratory), at the Centre d’études nordiques (CEN – Centre for Northern Studies), Université Laval in Québec City, Canada. However, the old version of the CDD had shortcomings, such as the absence of insertion of “Z” data (core level) as well as the lack of integration into a geographic information system (GIS).

Throughout a recent M.Sc. project (Sirois, 2011)¹, a new data structure was developed. Established on a relational database model, the CDD is designed to accommodate sediment core level data as well as the original biogeographic diatom data. As a result, the CDD data can easily be used for spatial analysis and its integration into a data server now allows its diffusion via networks. A user interface with search forms makes it possible to explore the results of the CDD in simple and precise ways.

Recent data acquisition and addition tripled the amount of information within this new version of the CDD. It now contains 572 samples, 40 114 occurrence data and more than 15 000 limnological data points. Its geographic range extends over eight geographic regions of the circumpolar Arctic, distributed across three continents: North America, Europe and Asia.

The CDD aims to become an international reference for paleolimnologists. To achieve this goal, the scientific community is encouraged to contribute to the project by sharing their data. Several developments are planned for the CDD, including the integration into a network and the creation of a web page with spatial representation of its contents. In addition to facilitating access to the data, these initiatives intend to increase the visibility of the database project and to encourage contributions.

¹Sirois, M., (2011). Développement d’un système d’information pour la paléolimnologie : la base de données des diatomées circumpolaires (Circumpolar Diatom Database - CDD). Mémoire de maîtrise, Université Laval, Québec, 181p.

The Laboratoire de Paléoécologie Aquatique (LPA – Aquatic Paleoecology Laboratory) is a group of research scientists, post-doctoral fellows and graduate students in the fields of paleolimnology and paleoceanography, in both the departments of geography and biology, dedicated to using paleoecological techniques to provide historical perspectives to environmental changes.

The paleolimnological research in this laboratory focuses on the use of fossil freshwater algae (diatoms and dinoflagellate cysts), insects (chironomid larvae) and microcrustaceans (ostracods) preserved in freshwater and marine sediment archives to reconstruct changes in climate and the environment during the Quaternary and post-glacial times.

Studies have been completed in Labrador, northern Québec (Nunavik), Nunavut (Foxe Basin, Canadian mid- to high Arctic), Yukon, Northwest Territories, Scandinavia, Spitsbergen, Siberia and Patagonia. The laboratory has administered the Circumpolar Diatom Database (CDD), which contains information from more than 550 lakes, since 1997.

The CDD project was initiated by Reinhard Pienitz, ArcticNet. The server integration and web design phases were funded by Reinhard Pienitz via financial support obtained from the Natural Sciences and Engineering Research Council of Canada (NSERC) and by grants from the Centre d’études nordiques (CEN – Center for Northern Studies) at Université Laval.

The website was designed and built by Martin Sirois and Reinhard Pienitz with the help of Luc Cournoyer. The data are stored on a SQL Server system located at the CEN head office in Quebec City, Canada.

The CDD website was built using Twitter Bootstrap v2.3.1 .