Fróðskaparrit - 31.12.2000, Side 46

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A REVIEW OF PLANT COMMUNITIES OF THE FAROEISLANDS
Carex spp. and Eriophorum species. Os-
tenfeld (1905-1908) described the associa-
tion Cyperacae - Sphagnum with consider-
able amounts of mosses and higher plants
such as Eriophorum angustifolium, E. vagi-
natum, Narthecium ossifragum, Carex pan-
icea, Carex nigra, and Pinguicula vulgaris.
Three types of mires are found in the Faroe
Islands, topogenic, soligenic, and ombro-
genic. Raised bogs are not found in the is-
lands. Topogenic mires are overgrown
lakes, soligenic mires are found on hill
slopes, and ombrogenic mires are found in
valleys and are the so-called “blanket
mires”. In ombrogenic mires, Hobbs and
Averis (1991) found that the vegetation was
similar to the British Scirpus - Eriophorum
blanket-bog Juncus squarrosus - Rhytidi-
adelphus loreus sub-association. In soli-
genic mires, the Carex dioica - Pinguicula
vulgaris association was found.
Dierssen (1982) compared the mire veg-
etation in Iceland, Norway, the British
Isles, and the Faroe Islands. He described
the following three facies of the Campylio
- Caricetum dioiciae association in the
Faroe Islands: facies Carex tumidicarpa,
facies Carex pulicaris, and facies Carex
dioica. He described the following three
associations: Caricetum nigeria associa-
tion, Triglochino - Juncetum triglumis as-
sociation, and Scapanio - Narthecium os-
sifragi association.
In springs, Hobbs and Averis (1991)
found the Philonotis fontana - Saxifraga
stellaris association rich in Carex nigra,
Drepanocladus fluvitans, and Dicranella
palustris. A Philonotis association was
also described by Ostenfeld (1905-1908).
Fresh Water Vegetation
Swamp vegetation has a very limited dis-
tribution in the Faroe Islands and is only
found at the margin of natural lakes, small
ponds, and ponds formed as a result of the
cutting of peat. Larger areas with swamp
vegetation play a minor role. Associations
found in freshwater are the Eleocharis as-
sociation, with character species Carex
salina and Equisetum fluviatile', the
Menyanthes - Potamogeton association,
with Menyanthes trifoliata, Potamogeton
polygonifolius, and other plants, such as
Ranunculus flammula (Ostenfeld, 1905-
1908). Freshwater in the Faroe Islands is
poor in nutrients. The most common plants
in freshwater with gravel bottom are
Isoetes echinospora, I. lacustris, Littorella
uniflora, Ranunculus flammula, Subularia
aquatica, and Juncus bulbosus. On soft
bottom, the common species are Spargani-
um angustifolium and Myriophyllum al-
terniflorum, and species of Potamogeton,
such as P. natans, P.gramineus, and P. per-
foliatus. Ostenfeld (1905-1908) described
a Littorella association and a Sparganium -
Potamogeton association.
Coastal Vegetation
Most of the coasts in the Faroe Islands are
more or less vertical cliffs, commonly up to
several hundred metres. These rocky
shores present a characteristic pattern of
horizontal vegetation zones composed pri-
marily of lichen species. Lichen species in
these horizontal zones occupy habitats ac-
cording to their tolerance of the influence
of seawater. Verrucaria maura and Lichi-
na confinis form the zone closest to the sea,