FOREST CANOPY COMPOSITION (SNF)

The purpose of the SNF study was to improve our understanding of the relationship between remotely sensed observations and important biophysical parameters in the boreal forest. A key element of the experiment was the development of methodologies to measure forest stand characteristics to determine values of importance to both remote sensing and ecology. Parameters studied were biomass, leaf area index, above ground net primary productivity, bark area index and ground coverage by vegetation. Thirty two quaking aspen and thirty one black spruce sites were studied. Sites were chosen in uniform stands of aspen or spruce. Aspen stands were chosen to represent the full range of age and stem density of essentially pure aspen, of nearly complete canopy closure, and greater than two meters in height. Spruce stands ranged from very sparse stands on bog sites, to dense, closed stands on more productive peatlands. Within each plot, all woody stems greater than two meters in height were recorded by species and diameter breast height (dbh), height of the tree, and height of the first live branch dimensions were measured. The depth of crown was also calculated. Similar measurements were made for shrubs between one and two meters tall in the aspen sites.