A study of the ecology of the oceanic montane vegetation of western Ireland and its potential response to climate change
View/ Open
Date
2012-12-03Author
Hodd, Rory
Metadata
Show full item recordUsage
This item's downloads: 8956 (view details)
Abstract
Within Europe, montane oceanic vegetation is restricted to areas with an oceanic climate, such as western Ireland. It was found that a wide range of montane heath and associated vegetation occurs in western Ireland, and can be dominated by dwarf shrubs, bryophytes or graminoid species. Montane vegetation dominated by bryophytes, especially the moss Racomitrium lanuginosum, is particularly restricted to oceanic areas. Much variation occurs in this vegetation along altitudinal and latitudinal gradients, with exposure exerting a particularly important influence on the composition of montane vegetation in Ireland.
The ecology of a community of large leafy liverwort species, known as the mixed northern hepatic mat, was also studied. This community grows only in western Ireland and western Scotland and has highly specific climatic requirements, requiring frequent, high rainfall and a narrow range of microclimatic conditions. Climatic conditions were measured in hepatic mat sites using temperature and humidity dataloggers. The habitat preference of hepatic mat vegetation was found to vary along a latitudinal gradient, occurring in heath under Calluna vulgaris in the north-west of Ireland, and on open grassy slopes in the south-west of Ireland.
A particularly pressing threat to these montane plant communities is climate change. Projections, from species distribution models, suggest that there may be a future reduction in suitable climate space for the species that make up these communities in Ireland. Bryophyte species, particularly those of hepatic mat, are projected to lose climate space in the south of their range and gain space in the north, which they are unlikely to colonise due to limited dispersal capacity. Many species of montane heath are projected to lose space and suitable conditions are projected to occur at only the highest altitudes in Ireland. Therefore, it is likely that the montane vegetation will be negatively impacted by climate change in the future.