CS34 River Dynamics
Date: Wednesday, June 12, 2002
Time: 2:30:00 PM
Location: View Royal
 
KingsleyM, University of Ottawa, Ottawa, Canada, mkingsle@science.uottawa.ca
Pick, F, , University of Ottawa, Ottawa, Canada, frpick@science.uottawa.ca
 
THE EFFECTS OF NUTRIENTS AND CURRENT VELOCITY ON PERIPHYTON BIOMASS IN FRASER RIVER TRIBUTARIES, BRITISH COLUMBIA
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Epilithic periphyton are important in lotic ecosystems because of their predominance in the diet of invertebrates and also because of the adverse impacts from algal blooms. In order to determine the physical and chemical variables that best explain the variation in periphyton among rivers in British Columbia, riffle zones of 20 salmonid rivers in the Fraser River watershed were sampled during July and October, 2001. Velocity and turbidity were measured, along with a number of chemical characteristics (dissolved nutrients, total nutrients, conductivity, pH). Algal biomass estimated as chlorophyll a and ash-free dry mass was significantly higher in October than July, as was velocity and turbidity. No correlations were found between the July biomass and any of the parameters. However, significant correlations were found between the October periphyton chlorophyll, conductivity and phosphorus (both total and dissolved). Overall the ratio of TN:TP ranged from 2.4 to 160 suggesting substantial differences between rivers with respect to the nutrient that limits algal growth.