N15x Iberoatlantic fixed gray dunes
Description
Patchy communities of grasses, forbs and shrubs, including many Mediterranean lineages, growing in the innermost belt of sand dunes after a long period with no disturbances by storms.
Protection
The EU Habitat Directive grants them priority protection under the code 2130* ("Fixed coastal dunes with herbaceous vegetation ['grey dunes']").Floristic Composition
Frequent species
Indicator species
Phytosociology
- Festuco arenariae-Crucianelletum maritimae
- Helichryso stoechadis-Koelerietum arenariae
- Iberidetum procumbentis
Relations with other habitat types
These communities replace N133 in inner sand dune belts, only rarely disturbed by storms (be it directly through erosion or through the deposition of the wind-borne sand mobilised when the vegetation of more seaward areas is destroyed. Through excessive human pressure, essentially camping and beachgoing, these communities turn into V32Z or even into bare sands, resetting the succession and lesding to an inland advance of N13 communities. A new regional level IV category is created, since the apparently ad hoc N155 (“Biscay fixed gray dunes“), judging by its floristic definition, is at odds with most of the regional communities, especially the western ones; whereas the floristically more adequate N161 (“Mediterraneo-Atlantic fixed grey dunes") is in its definition explicitly excluded from the Iberoatlantic region.
Regional distribution
Present only in large sand dune systems, these communities have suffered heavily from human activities. The leaching of the salt and the build up of a continuous layer of organic soil, facilitated by carpets of poikilohydric mosses, enable the incipient, patchy establishment of woody plants, some proper to this sand-dwelling, subhalophilous communities and others arriving from the surrounding zonal vegetation. Forestry has thus been possible, mostly with pines and eucalypts, adding further anthropic pressure on these plant communities. Galicia and Portugal, where good examples remain, are ostensibly underrepresented in our dataset.
Known occurrences and potential area of occupancy of the habitat type in the study region.
