| Abstract/Description or Keywords |
This study used a paired-catchment approach to investigate the effects of harvesting on streamflow for Camp Creek, a snowmelt-dominated stream in the southern interior of British Columbia. The drainage area for Camp Creek is 33.9 km2, and 27 percent of the area was harvested in response to a pine beetle infestation. Adjacent Greata Creek, with a drainage area of 40.7 km2, served as a control. Harvesting resulted in a significant increase in April flows, which persisted with no evidence of recovery through the 18-year post-treatment period, as well as a significant advance in the timing of peak flows relative to those for the control stream. No significant nor apparent changes in seven-day low flows were detected. Peak flows appeared to increase for smaller events, but not for larger events, although this result was not statistically significant. Detection of significant harvesting effects on low flows, peak flows and annual water yield may have been hampered by inherent differences between the two catchments, particularly in relation to aspect and elevation distribution, as well as by the effects of a climate shift that coincided with the harvesting treatment, and which was associated with low snow accumulation throughout the post-treatment period. Problems with finding well-matched catchment pairs likely represent a fundamental limitation in applying the paired-catchment approach to estimate the effects of forest harvesting in medium to large catchments. |
