Habitat account - Marine, coastal and halophytic habitats


1420 Mediterranean and thermo-Atlantic halophilous scrubs (Sarcocornetea fruticosi

Background to selection

Distribution of SACs/SCIs/cSACs with habitat 1420 Mediterranean and thermo-Atlantic halophilous scrubs (Sarcocornetea fruticosi).  Click image for enlarged map.
Distribution of SACs/SCIs/cSACs with habitat 1420 Mediterranean and thermo-Atlantic halophilous scrubs (Sarcocornetea fruticosi). Click image for enlarged map.

Description and ecological characteristics

 

This scrubby, halophilous (i.e. salt-tolerant) vegetation develops in the uppermost levels of saltmarshes, often where there is a transition from saltmarsh to dunes, or in some cases where dunes overlie shingle. The form that most closely resembles the scrub vegetation of the Mediterranean is restricted to south and south-east England and is formed predominantly of bushes of shrubby sea-blite Suaeda vera and sea purslane Atriplex portulacoides (NVC type SM25 Suaeda vera drift-line community). This most frequently occurs at the upper limit of tidal inundation and is found in association with transitions to sand dunes or shingle structures. In a few localities on the south and east coast of England a similar community develops, but with dense stands of perennial glasswort Sarcocornia perennis with a small number of herbaceous species (SM7 Arthrocnemum perenne stands). Another local variant has reduced evidence of the characteristic shrubs and a greater abundance of herbaceous species, such as sea-lavenders Limonium spp. and sea-heath Frankenia laevis, in a matrix with more common saltmarsh species, such as annual sea-blite Suaeda maritima or thrift Armeria maritima (SM21 Suaeda vera – Limonium binervosum salt-marsh community).

European status and distribution

 

 

This habitat occurs in a number of EU countries.

UK status and distribution Click to view UK distribution of this habitat

 

In the UK this habitat occurs on the south and east coasts of England, with fragmentary outliers in Wales. Only three areas are known to support extensive examples of the habitat type.

Site selection rationale

 

All sites known to support extensive examples of this very rare habitat type have been selected. Isolated, fragmentary stands have not been included within the SAC series.


Site accounts

Chesil and the Fleet Dorset and Somerset
Chesil and the Fleet on the south coast of England contains a major concentration of Mediterranean and thermo-Atlantic halophilous scrubs in the UK. A band of shrubby sea-blite Suaeda vera and sea-purslane Atriplex portulacoides lines much of the 13 km length of the seaward margin of the Fleet. The community forms a clear zone between the Fleet and the shingle vegetation of Chesil Bank. It appears to exist in a dynamic equilibrium with Annex I type 1210 Annual vegetation of drift lines dominated by sea beet Beta vulgaris ssp. maritima, for which the site is also selected. This replaces the scrub in areas subject to disturbance, and is in turn displaced by the scrub after disturbance ceases.
Essex Estuaries Essex, Extra-Regio
In this complex of estuarine marshes on the east coast of England the occurrence of Mediterranean and thermo-Atlantic halophilous scrubs is currently artificially restricted by sea-walls. It now occurs principally as a strandline community or at the foot of sea-walls. Recent managed retreat schemes offer the prospect of future expansion of the habitat type. The local variant of this vegetation, which features sea-lavenders Limonium spp. and sea-heath Frankenia laevis, occurs at one location, Colne Point.
North Norfolk Coast East Anglia
The North Norfolk Coast, together with The Wash and North Norfolk Coast, comprises the only area in the UK where all the more typically Mediterranean species that characterise Mediterranean and thermo-Atlantic halophilous scrubs occur together. The vegetation is dominated by a shrubby cover up to 40 cm high of scattered bushes of shrubby sea-blite Suaeda vera and sea-purslane Atriplex portulacoides, with a patchy cover of herbaceous plants and bryophytes. This scrub vegetation often forms an important feature of the upper saltmarshes, and extensive examples occur where the drift-line slopes gradually and provides a transition to dune, shingle or reclaimed sections of the coast. At a number of locations on this coast perennial glasswort Sarcocornia perennis forms an open mosaic with other species at the lower limit of the sea-purslane community.
The Wash and North Norfolk Coast East Anglia, Lincolnshire
The Wash and North Norfolk Coast, together with the North Norfolk Coast, comprises the only area in the UK where all the more typically Mediterranean species that characterise Mediterranean and thermo-Atlantic halophilous scrubs occur together. The vegetation is dominated by a shrubby cover up to 40 cm high of scattered bushes of shrubby sea-blite Suaeda vera and sea-purslane Atriplex portulacoides, with a patchy cover of herbaceous plants and bryophytes. This scrub vegetation often forms an important feature of the upper saltmarshes, and extensive examples occur where the drift-line slopes gradually and provides a transition to dune, shingle or reclaimed sections of the coast. At a number of locations on this coast perennial glasswort Sarcocornia perennis forms an open mosaic with other species at the lower limit of the sea-purslane community.

SACs/SCIs/cSACs where this Annex I habitat is a qualifying feature, but not a primary reason for site selection

Not applicable.
 

Many designated sites are on private land: the listing of a site in these pages does not imply any right of public access.