SM2D Puccinellia maritima – Aster tripolium saltmarsh
Vegetation
This saltmarsh community is strongly dominated by Puccinellia maritima, which can form dense monospecific lawns. Usually, however, there is some Aster tripolium dotted throughout the sward. Plantago maritima, Triglochin maritimum, Glaux maritima, Spergularia media, Cochlearia officinalis and Spartina agg. are all occasional. Where the Puccinellia has lodged, some of these other species may not be immediately apparent. Salicornia agg. is also occasional, generally occuring where the sward is a bit more open. Mean maximum vegetation height = 47.2 cm, n = 15.
Ecology
This is a lower marsh community that is fairly frequently inundated. Conditions are base-rich (mean pH = 7.6, n = 15).
Sub-communities
No sub-communities have been described for this community
Similar communities
From the other communities in this group, community SM2D is chiefly differentiated by the dominance of Puccinellia maritima.
Conservation value
Almost all examples of this vegetation qualify as EU HD Annex I habitat 1330 Atlantic salt meadows. Where Sarcocornia perennis occurs, however, the vegetation is instead referable to habitat 1420 Halophilous scrub. This rare species of the southeast is also listed on the Flora Protection Order, 2015, as is Puccinellia fasciculata. This is typically a rather species-poor saltmarsh community (species/4 m2 = 5.5, n = 204), but 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.