Ireland: Submerged Prehistoric Sites and Landscapes

Evidence of Ireland's drowned landscapes and settlements presently comprises 50 sites spread across the entire island. These comprise mainly intertidal find spots or small collections of flint artefacts. A handful of fully subtidal sites are known, generally from nearshore regions and consisting, with one exception, of isolated single finds. Evidence of organic remains is also sparse, with the exception of Mesolithic and Neolithic wooden fish traps buried in estuarine sediments under Dublin. The relatively small number of sites is probably due to lack of research as much as taphonomic issues, and thus the current evidence hints at the potential archaeological record which may be found underwater. Such evidence could contribute to knowledge of the coastal adaptations and seafaring abilities of Ireland's earliest inhabitants. Nonetheless, taphonomic considerations, specifically relating to Ireland's history of glaciation, sea-level change and also modern oceanographic conditions likely limit the preservation of submerged landscapes and their associated archaeology. Realistically, the Irish shelf is likely characterised by pockets of preservation, which makes detection and study of submerged landscapes difficult but not impossible. A range of potential routes of investigation are identifiable, including site-scale archaeological survey, landscape-scale seabed mapping, archival research and community engagement

Biogeographical patterns in the British and Irish flora

The hectad (10 × 10 km square) distributions of the 1405 native British and Irish vascular plants were classified by the SPHERIKM cluster analysis program into 20 clusters, each of which is characterised by the key species used to initiate the cluster. The clusters reflect the influence of climate, altitude, geology and habitat on distribution patterns at this scale. Clusters with restricted distributions have high concentrations of threatened species, particularly the Medicago sativa cluster, centred on Breckland (55% of the species are threatened in Britain, although only 29% are regarded as priorities for conservation), and the Carex atrata cluster of montane species (45% threatened, and 49% conservation priority species). Some clusters are composed predominantly of species with similar European distributions whereas others are much more phytogeographically heterogeneous. A comparison with a similar analysis of the distribution of British and Irish mosses and liverworts reveals many similarities, especially between the vascular plants and the mosses, although there are many more common vascular plants than bryophytes and many more coastal species