The old Norway spruce forests of northern boreal Fennoscandia are alive and well: a review of Siren (1955)
Abstract:The long-term development and stability of the thick moss-conifer forests that occur throughout the circumpolar boreal zone have been a subject of debate since the early twentieth century. This study reviews Gustaf Siren's (1955) study “On the development of spruce forests on raw humus sites in north Finland and its ecology” (Acta Forestalia Fennica, 62), which has been one of the most influential investigations of these forests in Fennoscandia. Through a chronosequence of 71 stands and measurements of ecological conditions in two different stands over two summers, Siren formulated a model of stand development, in which forests undergo successive cycles of evenly aged stands. Central to the model was the declining productivity with each tree generation, until the next stand-replacing disturbance. This development was driven by accumulation of the raw humus layer and the subsequent poor ecological conditions for growth and regeneration. However, more recent results contradict Siren's model. The methodology, the main results and their historical context in Siren's model are presented and evaluated here. The significance and shortcomings of the results are discussed in the light of current knowledge of the long-term development of northern boreal Picea abies stands.
Document Type: Research Article
Publication date: February 1, 2011