SS3.07 Headwater Ecosystems in Forested Landscapes and Beyond
Date: Wednesday, June 12, 2002
Time: 11:00:00 AM
Location: View Royal
 
BothwellML, National Water Research Institute, Nanaimo, Canada, bothwellm@dfo-mpo.gc.ca
Clare, J, J, National Liberal Caucus, Ottawa, Canada, clarej@parl.gc.ca
MacIsaac, E, A, Fisheries and Oceans, Vancouver, Canada, macissace@pac.dfo-mpo.gc.ca
Macdonald, S, J, Fisheries and Oceans, Vancouver, Canada, macdonaldsj@pac.dfo-mpo.gc.ca
 
EFFECTS OF CLEAR-CUT LOGGING AND SOLAR ULTRAVIOLET RADIATION ON BENTHIC COMMUNITIES IN SMALL STREAMS
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The effect of logging on solar exposure (including UV radiation), water temperature, and dissolved nutrients in logged and unlogged reaches of the same stream was studied over two years. We examined the influence of these changes on the benthic algal and invertebrate communities. Clear-cut logging and removal of the forest canopy increased solar exposure, stream temperature, and nutrient loads. This resulted in large changes in the biomass and composition of benthic periphyton and invertebrate communities. The impact of elevated solar ultraviolet radiation following logging, while evident immediately inside cut blocks, was mediated by effects of elevated temperature and nutrient concentrations on algal and invertebrate communities