Vegetation in Danish beech forests: the importance of soil, microclimate and management factors, evaluated by variation partitioning

The importance of management regime on floristic variation (mosses and vascular plants) in four Danish beech forests was investigated. Sixty-four blocks were sampled, representing beech stands of different age and management types. Nineteen potential explanatory variables were recorded and tested with Monte-Carlo tests and Canonical Correspondence Analysis. In addition results were evaluated by use of Detrended Correspondence Analysis. Explanatory variables were divided into three groups; soil, microclimatic and management parameters. The amount of variation explained by each group of variables was calculated by use of variation partitioning. The group consisting of management variables explained most variation, on local as well as regional scale. Management related variables explained more variation in vegetation than any other variables together. This indicates the importance of management as determining species composition in Danish beech forests. Management related variables explained most variation on local scale. On a regional scale, soil parameters explained the major part of the variation. The results suggest that thirty years without management are sufficient to change species composition significantly, as compared to managed forests.