| The spatial patterns of trees and shrubs within the forest-tundra ecotones in the Mealy Mountains, Newfoundland and Labrador, and in the Ruby Ranges, Yukon Territory were characterized using spatial pattern analysis. The processes influencing the recruitment of juvenile trees into the adult population and how they may facilitate or hinder infilling and advance at Canada's treeline were inferred. In Labrador, trees were generally aggregated recruitment into the adult population could be regulated by facilitation. Conversely, in the Yukon, trees were generally regularly distributed, possibly influenced by competition. At both sites, trees were generally independent of shrub cover. The spatial arrangement of trees and shrubs at both sites could be influenced by various processes and physical site attributes, resulting indifferent patterns. In the future, treeline advance will likely be hindered by a lack of seedlings in Labrador. In the Yukon, both infilling and advance will likely occur. |
