The phytogeography of Scotland

Abstract

Summary The phytogeography of Scotland is discussed in relation to a new phytogeographical classification of British and Irish vascular plants. The flora is dominated by species in the Temperate and Boreo-temperate major biome classes; the Southern-temperate species form the third largest group. The northern classes (Arctic-montane, Boreo-arctic Montane, Wide-boreal and Boreal-montane) in Britain and Ireland include relatively few species, but are particularly well represented in Scotland; species in the Mediterranean elements are not well represented. Species with Oceanic affinities occur throughout Scotland, but are most numerous in the west and south-west; the absence of a large, nationally or inter-nationally significant group of Oceanic plants in the highly oceanic areas of north-west Scotland is remarkable. A classification of Scotland into three phytogeographical zones based on the major biome categories identifies a montane zone where the northerly species are concentrated and a lowland zone with temperate and southerly species; the inter- mediate zone is lacking in both extremes and even the more wide-ranging species are under-represented.