USING GIS IN THE MAPPING AND ANALYSIS OF LANDSCAPE AND VEGETATION PATTERNS ALONG STREAMS IN SOUTHERN IRELAND

Abstract:The aim of this study was to relate riparian landscape and vegetation patterns to plant species richness. Seventeen stream sites were selected in southern Ireland, and the vegetation within 20m-wide riparian strips was mapped using a global positioning system. Digital maps were created using geographic information systems, and vegetation/habitat classification was carried out at four levels (from broad habitat group to vegetation type). To analyse the structure of the riparian landscapes in the study area, a number of landscape indices were calculated using Patch Analyst software. Plant species richness and community structure were examined using belt transects perpendicular to the watercourse. Riparian zones in the study area are very heterogeneous and exhibit obvious gradients with reference to landscape composition and spatial configuration. This is the result of both natural disturbance caused by streams and human influence. Landscape structure indices were only weakly correlated with plant species richness in the riparian zones investigated, but they did explain most of the variation in the structure and composition of the plant communities.