| To address gaps in our understanding of the interrelationships between snow accumulation, snowmelt, meteorological conditions, and forest cover, a field investigation was undertaken at Mayson Lake and Upper Penticton Creek, in the south-central interior British Columbia. During 1995, 1996 and 1997, snow water equivalent (SWE) was measured at 576 stations over nine sites including three clearcuts, two mature spruce-fir stands, a mature pine stand, a juvenile pine and a juvenile-thinned pine stand, and a juvenile spruce-fir stand. Stand structure was described in detail at each station. Continuous measurements of meterological conditions and snowmelt using lysimeters were made at Mayson Lake in 1995.; Peak SWE, taken as that measured on April 1st, was less under forest cover than in the clearcuts, by 32% (at Mayson Lake) and 23% (at Upper Penticton Creek) in the mature spruce-fir, by 14% in the juvenile and juvenile-thinned pine, and by 11% in the mature pine. No difference was found between the juvenile spruce-fir stand and clearcut.; Continuous lysimeter measurements at Mayson Lake showed that maximum daily and average melt rates over the season were similar for the clearcut and both juvenile pine stands. However, on a daily basis, the lysimeters showed a substantially different progression in snowmelt in the juvenile-thinned pine relative to the unthinned stand.; Significant relationships between forest inventory variables and peak SWE and melt were found at the stand rather than plot scale. Standardized ratios of forest to clearcut peak SWE and melt (FOSWE and FOMR) were highly correlated with average stand crown length and basal area, respectively.; Incorporating the field data into a temperature-index and radiation budget snowmelt model highlighted the importance of quantifying the relationships between forest structure, meteorological conditions, and snowmelt. Improved understanding of the interrelationships between these variables is necessary to validate and improve the performance of snowmelt models over the broad range of forest types found in south-central B.C. (Abstract shortened by UMI.)... |
