EUNIS habitat classification 2012 > A - Marine habitats > A4 - Circalittoral rock and other hard substrata

Circalittoral rock and other hard substrata

English name: Circalittoral rock and other hard substrata

Description (English)

Circalittoral rock is characterised by animal dominated communities (a departure from the algae dominated communities in the infralittoral zone). The circalittoral zone can itself be split into two sub-zones; upper circalittoral (foliose red algae present but not dominant) and lower circalittoral (foliose red algae absent). The depth at which the circalittoral zone begins is directly dependent on the intensity of light reaching the seabed; in highly turbid conditions, the circalittoral zone may begin just below water level at mean low water springs (MLWS). The biotopes identified in the field can be broadly assigned to one of three energy level categories: high, moderate and low energy circalittoral rock (used to define the habitat complex level). The character of the fauna varies enormously and is affected mainly by wave action, tidal stream strength, salinity, turbidity, the degree of scouring and rock topography. It is typical for the community not to be dominated by single species, as is common in shore and infralittoral habitats, but rather comprise a mosaic of species. This, coupled with the range of influencing factors, makes circalittoral rock a difficult area to satisfactorily classify; particular care should therefore be taken in matching species and habitat data to the classification.

Source:
EUNIS habitat classification
Interpretation Manual of the habitats targeted by Resolution No. 4

Quick facts

EUNIS habitat type code A4
Bern Convention Resolution 4 habitat type (used for designation of Emerald sites)

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Species mentioned in habitat description

Not available

Other classifications

Classification Code Habitat type name Relationship type
Palaearctic Habitat Classification 200112 11.24 Sublittoral rocky seabeds and kelp forests overlap
CORINE Land Cover 5.2.3. Sea and ocean n/a
Marine Habitat Classification Britain/Ireland 0405 CR Circalittoral rock (and other hard substrata) same
Barcelona Convention 199812 IV.3. (CIRCALITTORAL) HARD BEDS AND ROCKS same
Biodiversity Action Plan Priority Habitats (UK) 35 Littoral and sublittoral chalk overlap
For relation to plant communities (syntaxa), see Vegetation types

History

Classification Code Habitat type name Relationship type
EUNIS Habitat Classification 200410 A4 Circalittoral rock and other hard substrata same
EUNIS Habitat Classification 200308 A3 Sublittoral rock and other hard substrata wider
EUNIS Habitat Classification 200202 A3 Sublittoral rock and other hard substrata wider
EUNIS Habitat Classification 199910 A3 Sublittoral rock and other hard substrata wider
EUNIS Habitat Classification 199811 A3 Sublittoral rock and other hard substrata wider
EUNIS Habitat Classification 199712 X15 Sublittoral rock (to 200m depth) same
Palaearctic Habitat Classification 199905 11.24 Sublittoral rocky seabeds and kelp forests narrower
Palaearctic Habitat Classification 1997 11.25 Sublittoral organogenic concretions narrower
Palaearctic Habitat Classification 1997 11.24 Sublittoral rocky seabeds and kelp forests narrower
Palaearctic Habitat Classification 1996 11.25   narrower
Palaearctic Habitat Classification 1996 11.24   narrower
Palaearctic Habitat Classification 1993 11.25   narrower
Palaearctic Habitat Classification 1993 11.24   narrower
CORINE Biotopes Classification 1991 11.25   narrower
CORINE Biotopes Classification 1991 11.24   narrower
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