LakePulse network: First Canada-wide assessment of lakes

Irene Gregory-Eaves, Dept. of Biology, McGill University

LakePulse is an NSERC-funded network dedicated to assessing the health of Canadian lakes.

To reach this goal, LakePulse is:

1) sampling 663 lakes selected using a stratified random sampling design;

2) compiling government lake monitoring records from across Canada into a centralized database;

3) analyzing the collected data and translating that knowledge to scientists, policy makers and other stakeholders.

In this presentation, I will review the overall structure of the program and highlight preliminary findings from analyses of biotic (e.g., plankton and subfossil assemblages) and abiotic (e.g., metals) indicators. The LakePulse network is integrating results across contemporary and historical time scales as we are conducting parallel analyses of samples from the water column and from natural archives preserved in lake sediment records.  For example, we have found that sedimentary diatom assemblages showed varying degrees of change between pre-industrial and contemporary times across different ecozones. Likewise, total mercury concentrations in Eastern Canadian lakes were found to be significantly greater in contemporary sediments relative to pre-industrial conditions, but the magnitude of change varied by ecozone. LakePulse’s work will provide a much-needed perspective on the spatio-temporal heterogeneity of lake ecosystems in Canada, a country that is a key steward of a significant proportion of global inland waters.