Global radiation within subarctic open forest canopies

• Published in: Canadian Journal of Forest Research
• Main Authors: Lafleur, Peter M., Mantha, Blair K.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1994
• Subjects: Ecology; Forestry; Global and Planetary Change; Churchill; Subarctic
• Online Access: http://dx.doi.org/10.1139/x94-139; http://www.nrcresearchpress.com/doi/pdf/10.1139/x94-139

Measurements of global solar radiation were made at six sites with varying architecture within a subarctic open forest near Churchill, Manitoba. Below-canopy radiation was determined from a network of nine sensors and the mean was compared with global radiation above the canopy. The ratio of below- to above-canopy radiation, R, ranged from 0.52 to 0.7 for the six sites. This range falls within the range of observations from other subarctic sites. At all sites, R was smaller for clear than for overcast skies; however, the differences were not statistically significant. The data from this study were combined with data from the literature in order to develop predictive equations for solar radiation at the floor of subarctic forests, based on easily derived forest parameters. Linear relationships were found between R and canopy closure (r 2 = 0.76) and between R and tree height (r 2 = 0.88).