Technical report 125

APPENDIX B: EUNIS HABITAT CODE DESCRIPTIONS

Descriptions of EUNIS habitat codes used in Table 2.2. A complete list of EUNIS habitat codes and descriptions are available via the European Environment Agency web site (http://eunis.eea.europa.eu/
habitats-code-browser.jsp
)

Habitat code Habitat name Description
A1 Littoral
rock and other hard substrata
Littoral rock includes habitats
of bedrock, boulders and cobbles which occur in the intertidal zone (the area
of the shore between high and low tides) and the splash zone. The upper limit
is marked by the top of the lichen zone and the lower limit by the top of the
laminarian kelp zone. Exposed shores tend to support faunal-dominated
communities of barnacles and mussels and some robust seaweeds.
Sheltered shores are most notable for their dense cover of fucoid seaweeds,
with distinctive zones occurring down the shore. In between these extremes of
wave exposure, on moderately exposed shores, mosaics of seaweeds and
barnacles are more typical.
A2 Littoral
sediment
Littoral sediment includes
habitats of shingle (mobile cobbles and pebbles), gravel, sand and mud or any
combination of these which occur in the intertidal
zone. Some intertidal sediments are dominated by
angiosperms, e.g. eelgrass beds on the mid and upper shore of muddy sand
flats, or saltmarshes and saline reedbeds (A2.5) which develop on the extreme
upper shore of sheltered fine sediment flats. Littoral sediments are found
across the entire intertidal zone, including the strandline. Sediment
biotopes can extend further landwards (dune systems, marshes) and further
seawards (sublittoral sediments). Sediment shores are generally found along
relatively more sheltered stretches of coast compared to rocky shores. Muddy
shores or muddy sand shores occur mainly in very sheltered inlets and along
estuaries, where wave exposure is low enough to allow fine sediments to
settle. Sandy shores and coarser sediment (gravel, pebbles, cobbles) shores
are found in areas subject to higher wave exposures.
A3 Infralittoral
rock and other hard substrata
Infralittoral rock includes
habitats of bedrock, boulders and cobbles which occur in the shallow subtidal
zone and typically support seaweed communities. The upper
limit is marked by the top of the kelp zone whilst the lower limit is
marked by the lower limit of kelp growth or the lower limit of dense seaweed
growth. Infralittoral rock typically has an upper zone of dense kelp (forest)
and a lower zone of sparse kelp (park), both with an understorey of erect
seaweeds. On the extreme lower shore and in the very shallow subtidal
(sublittoral fringe) there is usually a narrow band of dabberlocks [Alaria esculenta] (exposed coasts) or
kelps. Areas of mixed ground, lacking stable rock, may lack kelps but support
seaweed communities. In estuaries and other turbid-water areas the shallow
subtidal may be dominated by animal communities, with only poorly developed
seaweed communities.
A4 Circalittoral
rock and other hard substrata
Circalittoral rock is
characterised by animal dominated communities. 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 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.
A5 Sublittoral
sediment
Sediment habitats in the
sublittoral near shore zone (i.e. covering the infralittoral and
circalittoral zones), typically extending from the extreme lower shore down
to the edge of the bathyal zone (200 m). Sediment ranges from boulders and
cobbles, through pebbles and shingle, coarse sands, sands, fine sands, muds,
and mixed sediments. Those communities found in or on sediment are described
within this broad habitat type.
A6 Deep-sea
bed
The sea bed
beyond the continental shelf break. The shelf break occurs at variable depth,
but is generally over 200 m. The upper limit of the deep-sea zone is marked
by the edge of the shelf. Includes areas of the Mediterranean Sea which are
deeper than 200 m but not of the Baltic Sea which is
a shelf sea.
A7 Pelagic
water column
The water column of shallow or
deep sea, or enclosed coastal waters.
B Coastal
habitats
Coastal habitats are those
above spring high tide limit (or above mean water level in non-tidal waters)
occupying coastal features and characterised by their proximity to the sea,
including coastal dunes and wooded coastal dunes, beaches and cliffs.
Includes free-draining supralittoral habitats adjacent to marine habitats
which are normally only affected by spray or splash, strandlines
characterised by terrestrial invertebrates and moist and wet coastal dune
slacks and dune-slack pools. Excludes supralittoral rock pools and habitats
adjacent to the sea which are not characterised by
salt spray, wave or sea-ice erosion.
C Inland
surface waters
Inland surface waters are
non-coastal above-ground open fresh or brackish
waterbodies (e.g. lakes and pools (C1), rivers, streams and springs (C2)),
including their littoral zones. Includes constructed inland freshwater,
brackish or saline waterbodies (such as canals, ponds, etc.)
which support a semi-natural community of both plants and animals;
seasonal waterbodies which may dry out for part of the year (temporary or
intermittent rivers and lakes and their littoral zones). Freshwater littoral
zones (C3) include those parts of banks or shores that are sufficiently
frequently inundated to prevent the formation of closed terrestrial
vegetation. Excludes permanent snow and ice.
D Mires,
bogs and fens
Wetlands, with the water table
at or above ground level for at least half of the year, dominated by
herbaceous or ericoid vegetation. Includes inland saltmarshes and waterlogged
habitats where the groundwater is frozen. Excludes the water body and rock
structure of springs (C2) and waterlogged habitats dominated by trees or
large shrubs (F, G). Note that habitats that intimately combine waterlogged
mires and vegetation rafts with pools of open water are considered as
complexes.
E Grasslands
and lands dominated by forbs, mosses or lichens
Non-coastal land
which is dry or only seasonally wet (with the water table at or above
ground level for less than half of the year) with greater than 30% vegetation
cover. The vegetation is dominated by grasses and
other non-woody plants, including mosses, macrolichens, ferns, sedges and
herbs. Includes semiarid steppes, successional weedy vegetation and managed
grasslands such as recreation fields and lawns. Excludes regularly tilled
habitats (I) dominated by cultivated herbaceous vegetation such as arable
fields.
F Heathland,
scrub and tundra
Non-coastal land
which is dry or only seasonally inundated (with the water table at or
above ground level for less than half of the year) with greater than 30%
vegetation cover. Tundra is characterised by the presence of permafrost.
Heathland and scrub are defined as vegetation dominated by shrubs or dwarf
shrubs of species that typically do not exceed 5 m maximum height. Includes
shrub orchards, vineyards, hedges (which may have
occasional tall trees). Also includes stands of climatically-limited dwarf
trees < 3 m high, such as occur in extreme alpine conditions. Includes Salix and Frangula carrs but excludes coppice and Alnus and Populus swamp
woodland (G).
G Woodland,
forest and other wooded land
Woodland and recently cleared
or burnt land where the dominant vegetation is, or was until very recently,
trees with a canopy cover of at least 10%. Trees are defined as woody plants,
typically single-stemmed, that can reach a height of 5 m at maturity unless
stunted by poor climate or soil. Includes lines of trees, coppices, regularly
tilled tree nurseries, tree-crop plantations and fruit and nut tree orchards.
Includes Alnus and Populus swamp woodland and riverine Salix woodland. Excludes Corylus avellana scrub and Salix and Frangula carrs. Excludes stands of climatically-limited dwarf trees
< 3m high, such as occur at the Arctic or alpine tree limit. Excludes
parkland with canopy less than 10%, which are listed
under sparsely wooded grasslands (E).
H Inland
unvegetated or sparsely vegetated habitats
Non-coastal habitats with less
than 30% vegetation cover (other than in crevices of rocks, screes or cliffs)
which are dry or only seasonally wet (with the water table at or above ground
level for less than half of the year). Subterranean non-marine caves and
passages including underground waters and disused underground mines. Habitats
characterised by the presence of permanent snow and surface ice other than
marine ice bodies.
I Regularly
or recently cultivated agricultural, horticultural and domestic habitats
Habitats maintained solely by
frequent tilling or arising from recent abandonment of previously tilled
ground such as arable land (I1) and gardens (I2). Includes tilled ground
subject to inundation. Excludes lawns and sports fields (E), shrub orchards
(F), tree nurseries and tree-crop plantations (G).
J Constructed,
industrial and other artificial habitats
Primarily human settlements,
buildings, industrial developments, the transport network, waste dump sites. Includes highly artificial saline and
non-saline waters with wholly constructed beds or heavily contaminated water
(such as industrial lagoons and saltworks) which are
virtually devoid of plant and animal life. Excludes disused underground mines
(H1.7).
X01 Estuaries Downstream part of a river
valley, subject to the tide and extending from the limit of brackish waters.
River estuaries are coastal inlets where there is generally a substantial
freshwater influence. The mixing of freshwater and sea water
and the reduced current flows in the shelter of the estuary lead to
deposition of fine sediments, often forming extensive intertidal sand and mud
flats. Where the tidal currents are faster than flood tides, most sediments
deposit to form a delta at the mouth of the estuary. Baltic river mouths,
considered as an estuary subtype, have brackish water and no tide, with
helophytic wetland vegetation and luxurious aquatic vegetation in shallow
water areas. Littoral and sublittoral habitat types typical of estuaries are
included in A2 and A5, although many other habitat types including tidal
rivers may occur in estuaries.
X02 Saline
coastal lagoons
Lagoons are expanses of shallow
coastal salt water, of varying salinity and water volume, wholly or partially
separated from the sea by sand banks or shingle, or, less frequently, by
rocks. Salinity may vary from brackish water to hypersalinity depending on
rainfall, evaporation and through the addition of fresh seawater from storms,
temporary flooding of the sea in winter or tidal exchange. With or without
vegetation of seagrasses or charophytes. Habitat types typical of lagoons are
included in A5, although many other habitat types may also occur in lagoons.
X03 Brackish
coastal lagoons
Flads and gloes, considered a
Baltic variety of lagoons, are small, usually shallow, more or less delimited
water bodies still connected to the sea or cut off from the sea very recently
by land upheaval. Characterised by well-developed reedbeds and luxuriant
submerged vegetation and having several morphological and botanical
development stages in the process whereby sea becomes land. Mediterranean
lagoons may host the Ruppietum
community with halophytic vegetation, while at sites with a fresh water supply, plant communities of Juncetum and Phragmitetum
can develop.