A biogeographical study of plant communities and environmental gradients on South Uist, Outer Hebrides, Scotland

Abstract

Abstract Plant community types and underlying environmental gradients in the Outer Hebrides have not been described in detail, although a number of general accounts of the flora and vegetation exist. Satellite imagery was used to locate a transect for phytosociological survey across the island of South Uist. Species cover and a range of environmental variables were described for a total of 212 quadrats along this transect. Sixteen plant community types were identified using Two Way Indicator Species Analysis (TWINSPAN) and the prevailing environmental gradients were determined using Canonical Correspondence Analysis (CANOCO). The communities were related to the National Vegetation Classification of the British Isles and general plant communities previously described for the Outer Hebrides. The vegetational history of the transect area was also described from pollen analysis of a core obtained from Lake Hellisdale on the transect. The position of these 16 community types along the environmental gradients i...