Home > Environment > Water Quality > RSVL

RSVL

Under the Réseau de surveillance volontaire des lacs (RSVL), water quality is monitored by

• • Measuring water transparency (Secchi disk depth) each year (roughly every two weeks).

  • Collecting water samples for laboratory measurements of phosphorous, dissolved organic carbon and chlorophyll-a, Sampling is now done for 2-3 years then resumes after 4 years.

Phosphorous is naturally scarce in lakes, but stimulates the growth of plants and algae when it becomes too abundant as a result of human activities, Chlorophyll-a is an indicator of the amount of algae in a lake, and dissolved organic carbon is an indicator of lake water colour, which can influence transparency.

For Lac Mahon water-quality results on the RSVL website, see 

• Lac Mahon RSVL Water-Quality Results

The three indicators generally put Lac Mahon in the mesotrophic ("middle-aged") stage.

For comparison, see a 2016 report by ABV-7 for lakes at Kazabazua (filed in Shorelines).

One simple definition of trophic state is plant biomass (see Defining trophic state). Chlorophyll is the best predictor of biomass, and could therefore be used as a primary measure of trophic state classification.