Climate change and oceanic mountain vegetation: A case study of the montane heath and associated plant communities in western irish mountains

Plant communities in montane regions are useful for studying the potential eff ects of climate change. Many mountain species have affi nities with colder climates and may not survive local temperature rises. Although Irish mountains are not of high altitude and are infl uenced by the tempering eff ect of the Atlantic Ocean, they support some species of arctic–montane affi nity. In Ireland, the climate termed hyperoceanic, with its constant moisture and mild temperatures, prevails on western mountains. There it benefi ts the growth of bryophyte communities, which are more abundant due to higher cloud cover and precipitation as well as lower evapotranspiration. As these bryophyte communities occur up to c. 1000 m, alongside the arctic–montane higher plant species, they can be complementary as climate change indicators, as they respond diff erently to such change. There is little systematic information on the distribution of these scarce montane plant communities. Their distribution on the mountains of the west of Ireland is being mapped, and data are being gathered on the local climate of selected mountains. Th is will supply useful case-study material for climate change modelling, specifically providing information on regions that have little precise climatic information and on plant communities that are likely to be very vulnerable to aspects of climate change.