Coastal areas are typically rich in biodiversity. This is the result of the interaction of the wind and waves, working together to shape the rocks and sand and produce a range of niches in which specialised plants and animals can live. Our coastal lands contain a variety of habitats, including sand dunes and salt marshes.
Sand dunes form through the accumulation of sand over a long period of time. Sand dune vegetation varies widely and is related to the length of time since the sand was deposited, how stable the surface is, and other local conditions. Some dunes support very little vegetation, whereas others support a wide range of plant life.
Conservation Status of Sand Dunes
Sand dune habitats can be impacted by golf courses, farmland and tourism, and can be affected by hard sea defences that change the availability of new sand. Overgrazing leading to erosion is a concern in these habitats, but so is under-grazing of fixed dunes that often leads to a Marram grass-dominated sward with reduced species diversity. Many sand dunes in Ireland currently have an unfavourable conservation status.
Types of Sand Dunes
Three types of sand dune habitat are listed under the EU Habitats Directive that would benefit from more appropriate management by grazing:
- Fixed coastal dunes (EU code 2130)
- Dune slacks (EU code 2190)
- Machair (EU code 21A0)
For information on sand dunes within Ireland explore ‘Monitoring Survey if Annex I Sand Dune Habitats in Ireland’
Salt marshes are stands of vegetation that occur in marine and brackish conditions, mainly on sand and mud that is waterlogged or periodically submerged by the sea. They are typically found between the upper limits of the neap and spring tides in protected bays, estuaries, and other sections of sheltered coastline. Saltmarsh is widely distributed around the coast, but it is often not an extensive habitat.
Conservation Status Salt Marsh
Many salt marshes in Ireland currently have an unfavourable conservation status, due mainly to pressures from agriculture, including unsuitable grazing regimes and land reclamation. The invasive non-native species common cord-grass (Spartina anglica) also has a negative impact on salt marsh habitats by displacing native plant species and reducing biodiversity.
Types of Salt marsh
There is one type of salt marsh habitat listed under the EU Habitats Directive that would benefit from more appropriate management by grazing:
- Atlantic salt meadows (EU code 1330)
For recent information on salt marshes within Ireland explore ‘Saltmarsh Monitoring 2017-2018’