SM2A Puccinellia maritima – Glaux maritima saltmarsh
Vegetation
This saltmarsh community is dominated by Puccinellia maritima, with Aster tripolium, Plantago maritima and Armeria maritima also constants. Frequently, one will also find some Glaux maritima, Spergularia media and Triglochin maritimum and occasionally some stems of Salicornia agg., Cochlearia officinalis agg., Suaeda maritima and Limonium humile. Mean maximum vegetation height = 41.2 cm, n = 6.
Ecology
This is a common lower marsh community that is fairly frequently inundated. Conditions are base-rich (mean pH = 7.4, n = 6).
Sub-communities
No sub-communities have been described for this community
Similar communities
SM2A is essentially the ‘typicum’ Puccinellia community. It is a bit more diverse than SM2D and Puccinellia is not so overwhelmingly dominant. Atriplex portulacoides is much less abundant here than it is in community SM2B. This vegetation occurs a little higher in the marsh than SM2C so Salicornia agg. and Limonium humile are found much less frequently.
Conservation value
Almost all examples of this vegetation qualify as EU HD Annex I habitat 1330 Atlantic salt meadows. It is typically a medium richness saltmarsh community (species/4 m2 = 6.9, n = 181) and the species that are present are specialists.
Management
The main immediate threats to this saltmarsh community are probably grazing by livestock and invasion by Spartina agg. Sea-level rises as a result of climate change will have an impact, particularly in areas susceptible to coastal squeeze.