IRISH WETLAND WOODS - THE PLANT-COMMUNITIES AND THEIR ECOLOGY

Floristic and environmental data were recorded from wetland woods in a ll regions of Ireland, with more intensive studies in the Killarney ar ea. The principal gradients in the environment are found to be edaphic and hydrological. Seven vegetation groups are distinguished; two repr esent communities not hitherto described from Ireland. Group A is most ly riparian woodland and equates with the Salicetum albo-fragilis. Gro up B is found in stagnant conditions, mostly near lake shores, and cor responds to the Osmundo-Salicetum atrocinereae. Group C1, a rare commu nity of mires irrigated by calcareous groundwater, equates with the Al nus glutinosa-Carex paniculata community; one site corresponds to clas sic swamp carr. Group C2, typically associated with springs or flushed sites, largely equates with the Carici remotae-Fraxinetum. Group D, o n soils that are waterlogged in winter but dry out in summer, is class ified as the deschampsietosum caespitosae subassociation of the Corylo -Fraxinetum. Group E, associated with oligotrophic peat that is relati vely dry, equates with the Betuletum pubescentis. Group F, of waterlog ged oligotrophic pear, equates with the Sphagnum palustre-Betula pubes cens community. The richness and diversity of Irish wetland woods have been underrated; we emphasise the need for active conservation measur es.