Understory vegetation as a forest ecosystem driver: evidence from the northern Swedish boreal forest

Vegetation research in boreal forests has tended to focus on the tree component, while little attention has been paid to understory components such as dwarf shrubs, mosses, and reindeer lichens. However, the productivity of understory vegetation is probably comparable to that of the trees. We review recent research in the boreal forest of northern Sweden to highlight the ecological importance of understory vegetation, both in the short term by influencing tree seedling regeneration, and in the longer term by affecting belowground processes such as decomposition, nutrient flow, and buildup of soil nutrients. Wildfire resulting from lightning strike is a primary determinant of understory vegetation, and as such is a major driver of forest community and ecosystem properties. Forest management practices that alter the fire regime and the composition of understory vegetation may have long-term consequences for both conservation goals and commercial forest productivity.