Because ecotones often represent the physiological or competitive limit-of-distribution of species, they serve to define a species? local distribution. We take a relatively new approach to gradient analysis to quantify the changes in forest dominance (basal area of dominant tree species) and environmental factors (elevation, slope, aspect, intercepted photosynthetically active radiation [PAR], summer soil moisture, and soil depth and texture) across current lodgepole pine (Pinus contorta) ecotones in Rocky Mountain National Park, Colorado, USA. Based on canonical correspondence analysis on data from eight 20 m wide, 140?480 m long vegetation transects, we found that lodgepole pine distribution, is described generally by elevation and [...]
