Environmental factors and ecological processes in boreal forests

Climate, solar radiation, soil moisture, soil temperature and the presence of permafrost, the forest floor organic layer, nutrient availability, insect outbreaks, and wildfires interact to contribute to the mosaic pattern of forest types and the wide range in stand productivity characteristic of boreal forests. This review identifies the critical processes and parameters required to understand the ecology of boreal forests, providing a framework for a circumpolar comparison of boreal forests and a mechanistic context for climatic-biogeographic classifications of boreal forest regions. This conceptual scheme has been quantified in a simulation model of boreal forest dynamics. This model simulated local, seasonal patterns of solar radiation, soil moisture, and soil freezing and thawing for different topographies at Fairbanks, Alaska, and annual regional patterns of the same processes throughout the boreal forests of North America, Scandinavia, and the Soviet Union. It also simulated forest structure and vegation patterns in several conifer, hardwood, and mixed-conifer hardwood forests in different bioclimatic regions of northern North America. Though not floristically complex, boreal forests are complex in the environmental factors required to understand boreal ecology and the interactions among these factors. -from Authors