Abstract/Description or Keywords |
The effects of forest harvesting on water quality in Dennis Creek, a high elevation tributary of Penticton Creek in the Okanagan Valley, British Columbia, were monitored during the second year following clearcutting of 25% of the measured portion of the Dennis Creek watershed. Water samples were taken above and below the logged areas, from an adjacent unlogged watershed and from the main Penticton Creek. Logging appears to have resulted in a significant increase in water colour and minor increases in potassium, sodium chloride, electrical conductivity, total organic carbon and dissolved solids. Sediment concentrations increased, but remained at negligibly low levels. Calcium, silica, and hardness also increased slightly, but the changes could not definitely be attributed to logging effects. No significant changes were detected in total Kjeldahl nitrogen, nitrate, total phosphorus, magnesium, alkalinity, pH, sulphate or total inorganic carbon. With the exception of colour, values of all parameters remained well within desirable drinking water standard limits. In addition, with the exception of one sample, nitrogen levels also remained below the minimum threshold limit for potential over-production of aquatic plants. forest harvest |