Evaluation of relationships between understory light and aspen basal area in the British Columbia central interior

Abstract Data from twenty, 9–40-year-old, aspen ( Populus tremuloides Michx.) stands in four biogeoclimatic zones of northeastern and central British Columbia (BC) were analyzed to determine whether relationships between under- and within-canopy light availability (measured using the LiCor LAI-2000) and aspen abundance were similar between ecosystems. A logarithmic model provided the best-fit for these data, explaining 51–81% or 51–82% of the variation in light availability when aspen basal area (BA a ) or aspen relative density (RD a ), respectively, was the independent variable. Relationships between understory light and BA a or RD a differed significantly ( p Vertical light gradients were also measured to a height of 8 m within aspen canopies. Light availability increased rapidly with relative height in the canopy, especially where transmittance to the understory was low. As with understory light, relationships differed significantly ( p