AN EVALUATION OF LOCAL AND REGIONAL DIVERSITY OF BENTHIC MACROINVERTEBRATE COMMUNITIES IN TWO SMALL REGIONS OF IRELAND AND THEIR POTENTIAL AS LOCALISED REFUGIA FOR CERTAIN TAXONOMIC GROUPS

摘要

The objective of this study was to evaluate the taxonomic diversity of freshwater benthic macroinvertebrate communities in two small geographical regions of Ireland and assess their potential as critical refugia for local recolonisation in the future. Areas were identifi ed from previous studies as potentially supporting a high diversity of aquatic macroinvertebrates. Six rivers in the Slieve Bloom Mountains and fi ve rivers in the Killarney region of County Kerry were sampled. Where possible, each river was sampled at intervals along its course at source, 2.5km, 5km and 10km. The local and regional taxonomic richness and β-diversity were assessed at all sites. The results showed that both regions have many healthy freshwater systems and a high occurrence of selected Irish benthic macroinvertebrate species. The local richness and diversity was found to be low, with a high heterogeneity among sites sampled. The regional richness and diversity was high, however, indicating the importance of both regions for benthic macroinvertebrate diversity in Ireland and their potential to act as local refugia in the future. The protection of these regions may be extremely important in providing refuge populations in the future from which surrounding areas can be re-populated, facilitating ecological recovery as required by the Water Framework Directive.