Fróðskaparrit - 01.01.2004, Síða 228

226 ALTITUDINAL DISTRIBUTION OF PLANT COMMUNITIES IN THE FAROE ISLANDS
Table 4 continued
Additional species with constancy less than III: Agrostis stolonifera, Alchemillafaroensis, Alchemillafilicaulis, Armeria maritima, Aulacomnium turgidum,
Breutelia chrysocoma, Bryumsp., Calluna vulgaris, Campylopus schwarzi, Cardaminopsis petraea, Carex binemis, Carex demissa, Carex echinata, Carex
nigra, Carex pulicaris, Carex saxatilis, Cerastium alpinum, Cerastium fontanum, Cerastium nigrescens, Cetraria islandica, Cladonia arbuscula, Cladonia
cervicornis, Cladonia portentosa, Cladonia uncialis, Conostomum tetragonum, Dicranella sp., Dactylorhiza maculata, Deschampsia alpina, Deschampsia
cespitosa, Dicranum bonjeanii, Dicranum sp., Drepanocladus uncinatus, Equisetum palustris, Eriophorum vaginatum, Euphrasia arctia, Eupltrasia
frigida, Euphrasia micrantha,, Euphrasia scottica, Huperzia selago, Hylocomium splendens, Hypericum pulchrum, Isopterygium pulchellum, Isothecium
myosuroides, Juncus biglumis, Juncus bufonius, Juncus squarrosus, Juncus trifidus, Juncus triglumis, Koenigia islandica, Luzula arcuata, Luzula spicata,
Carex pilulifera, Luzula sylvatica, Mnium hornum, Narthecium ossifragum, Peltigera canina, Plagiothecium undulatum, Plantago maritima, Pleurozium
schreberi, Poa alpina, Poa glauca, Pogonatum urnigerum, Pohlia nutans, Polygala serpyllifolia, Polygala vulgaris, Prunella vulgaris, Pyrola minor,
Racomitrium affine, Racomitrium canescens, Racomitrium microcarpon, Ranunculus acris ssp. pumilus, Ranunculus acris, Ranunculus repens, Rhinantlius
minor, Rhodiola rosea, Rhytidiadelphus loreus, Rhytidiadelphus triquetrus, Rumex acetosa, Saxifraga hypnoides, Saxifraga rosacea, Saxifraga stellaris,
Sedum villosum. Silene acaulis, Sphagnum spp,, Taraxacum officinalis coll.-, Thuidium tamariscinum, Thymus praecox, Trichophorum cespitosum, Vaccinium
myrtillus, Veronica officinalis, Viola riviniana
osa-Rhytidiadelphus loreus community
had the lowest pH in this vegetation group
(5.3), the highest vegetation cover (89%),
and a medium number of taxa (60). The
last community in this vegetation type, the
Festuca vivipara-Agrostis capillaris com-
munity, had a relatively high pH (5.6), low
vegetation cover (35%), and was rich in
species (132). The Bistorta vivipara-Fes-
tuca vivipara and Deschampsia flexuosa-
Rhytidiadelphus loreus communities were
found only on north-facing slopes.
Racomitrium vegetation (Table 4), found
in about one quarter of all the sample plots
(129), was classified into three communi-
ties. It differs from open grassland-vegeta-
tion due to a high abundance of Racomitri-
um lanuginosum and Salix herbacea. The
vegetation cover parameter ranged from
67% to 94% and the pH varied from 5.3
to 5.5. The three communities are relatively
rich in taxa, 83 taxa for the Racomitrium
lanuginosum community, 88 taxa for the
Racomitrium lanuginosum-Salix herbacea
community, and 40 taxa for the Racomitri-
um fasciculare-Alchemilla alpina commu-
nily. This last communitiy was l'ound only
on south-facing slopes.
The moist grassland vegetation (Table 5)
was classifíed into three communities. The
vegetation cover was high (87% to 98%)
and the pH varied from 5.1 to 5.3. The
number of sample plots was 95. Character-
istic for this vegetation type is the domi-
nance of Nardus stricta and the richness
of bryophyte species, such as Hylocomium
splendens, Rhytidiadelphus loreus and R.
squarrosus. Bryophyte richness was espe-
cially characteristic of the Galium saxati-
lis-Anthoxanthum odoratum community,
and, to a lesser degree, of the Nardus stric-
ta-Potentilla erecta community. The moist
grass heath vegetation is poor in dwarf
shrub species although Vaccinium myrtil-
lus is still frequent, and, to a lesser degree,
Empetrum nigrum in the Thymus praecox-
Vaccinium myrtillus community; however,
Calluna vulgaris almost disappears.
In contrast to the moist grassland veg-
etation, the dwarf shrub heath vegetation
(Table 6) has a dominance of species such
as Calluna vulgaris and Empetrum nigrum.
Two communities were defined: Empetrum
nigrum-Calluna vulgaris community and
Calluna vulgaris-Nardus stricta communi-
ty. This vegetation type included 37 sample
plots. The vegetation cover was high (94%
to 98%) while the lowest pH values (5.2