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 re corded and tested with Monte-Carlo tests and Canonical Correspondence Analysis. In addition results were evaluated by use of Detrended Corre spondence Analysis. Explanatory variables were divided into three grou ps; soil, microclimatic and management parameters. The amount of varia tion explained by each group of variables was calculated by use of var iation partitioning. The group consisting of management variables expl ained most variation, on local as well as regional scale. Management r elated variables explained more variation in vegetation than any other variables together. This indicates the importance of management as de termining species composition in Danish beech forests. Management rela ted variables explained most variation on local scale. On a regional s cale, soil parameters explained the major part of the variation. The r esults suggest that thirty years without management are sufficient to change species composition significantly, as compared to managed fores ts.