SPECIES DENSITY OF PHANEROGAMS AND BRYOPHYTES IN DUTCH FORESTS

In Dutch forests the species density of vascular plants ranges from 1 to 61 species per 300 m(2). The vascular plant species density is high in the coastal dunes, southern Limburg, river valleys, and fen areas. With the exception of southern Limburg, these areas constitute the Ho locene part of the Netherlands. Low species densities occur in the san dy centre of the country. To a large extent, the areas of high species density of vascular plants follow the main river valleys. The bryophy te species densities range from 0 to 21 species per 300 m(2). High bry ophyte species densities occur mainly in the sandy centre and in the n orth-eastern part of the Netherlands. The highest species densities oc cur in fen woodlands and derelict coppices. Bryophyte species density is low in the coastal dunes and the very young woodlands in the recent ly reclaimed areas (polders). The species density contour maps of vasc ular plants and bryophytes in the Netherlands have little in common.