About the Lake Montjoie Observatory

The Lake Montjoie Plankton Observatory is a cabled automated profiling platform located in the Eastern Townships  (Quebec, Canada). The platform is cabled to shore and fully controlled from the University of Sherbrooke.

The observatory is used to study the seasonal growth and succession of phytoplankton species throughout the year, while also allowing processes that occur on event timescales to be resolved. State-of-the-art sensors collect observations of phytoplankton and their grazers as well as important environmental variables controlling algal growth.

The platform was first deployed in the summer of 2012. After a few engineering challenges, we collected a unique database that is currently being analyzed. Our next deployment is planned for the spring of 2013.

The instrumented profiling platform is shown to the right. It was designed and developed by WET Labs, Inc.

On the platform, 3 instruments are dedicated to observing plankton:

1) Imaging FlowCytobot

This instrument was developed by Rob Olson and Heidi Sosik at the Woods Hole Oceanographic Institution. We are extremely fortunate that they built one for us! The Imaging FlowCytobot is a submersible flow cytometer that captures images of the particles passing through it. It can observe particles in the ~5 um to 100 um range, and thus it captures images of individual phytoplankton cells. To see examples of images captured by our observatory, click above on the “Phytoplankton Imagery” tab in the main menu. Be prepared to wait a minute or so as we are still working on speeding up our server.

2) Underwater Video Profiler (a collaboration with Beatrix Beisner of UQAM)

This instrument was developed at the Laboratoire d’Océanographie de Villefranche by Marc Picheral and Gaby Gorsky. It is manufactured by Hydroptic. The Underwater Video Profiler can capture images of particles in the range of ~100 um to several cm. When we have completed our data handling procedure, we will post the images on this website.

3) ECO Triplet

This sensor is a fluorometer-backscattering meter manufactured by WET Labs, Inc. We use it to measure chlorophyll fluorescence (EX/EM 440/660 nm) as a proxy of phytoplankton biomass, as well as backscattering at 470 nm.

On the platform, 4 instruments measure environmental parameters that influence phytoplankton growth:

1) APNA nutrient analyzer

This instrument is built by Subchem. It measures nutrients (wet chemistry) in profile mode. In our configuration, it measures nitrate and phosphate.

2) Hyperspectral irradiance sensor

The HyperOCR is made by Satlantic. It measures the downwelling planar irradiance (i.e., the available light) every 3 nm in the visible wavelength range.

3) CTD

Seabird SBE19plus V2 - Conductivity, temperature, oxygen.

4) Doppler velocimeter

The Vectrino I is made by Nortek. This instrument measures the velocity of water in small volumes of water. Our objective is to have a measure of turbulence.

This website was developed to present and distribute our data (ask Yannick Huot for access to our database). It also provides a quick look at lake conditions in quasi-real time.

The lake observation platform is one of our main research projects at the Canada Research Chair in Earth Observation and Phytoplankton Ecophysiology (Department of Applied Geomatics, Université de Sherbrooke).

The processing and database underlying the website were made possible by the hard work of two interns: Maxime Fradette and Anahid Kasbarian. The website was designed by Carina Poulin.

This infrastructure is supported by funding from:

Last 7 daysLast_7_Days.html
Phytoplankton ImageryImagery.html
Last profileLast_Profile.html
The Observatory
Last 6 monthsLast_183_Days.html