Biomass and production of plankton size classes in 10 lakes of the Boreal Canadian Shield (1982)

Chlorophyll biomass and primary production were estimated for three size classes of phytoplankton (< 64 µm, < 25 µm, <10 µm at 8 dates during summer 1982. Water quality (conductivity, Secchi transparency, alkalinity, total phosporus, Hypolimnetic oxygen saturation) and morphometric attributes (mean and maximum depths, surface, volume, perimeter and length) were also measured in each lake. Plankton biomass and primary production were negatively related to water transparency, and increased with lake trophic state. Primary production of each size fraction seemed constant at all trophic states (50% for the < 10 µm size class, 70% for the < 25 µm). However, the small fraction (< 10 µm) contributed more in oligotrophic and eutrophic lakes than in mesotrophic lakes. Thus small size algae play a key role in controlling water transparency. Biomasse et production du nannoplancton par classes de taille dans 10 lacs du Bouclier canadien (1982) – M.Sc mémoire en Français Biomass and production of plankton size classes in 10 lakes of the Boreal Canadian Shield (1982) – Master thesis in French