Fróðskaparrit - 01.01.1987, Page 98

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THE ECOLOGY OF SOME MARINE AND MARITIME LICHENS
from the shore. Aspicilia caesiocineria in-
vaded at loc. 59 for the first time here, but
at loc. 57 it was also found in the m.s.l.
zone.
In addition to Anaptychia fusca, Fletcher
(1973) Rhizocarpon constrictum, Lecanora
atra, and Ramalina siliquosa as an indica-
tor. In the Faroe Islands Lecanora atra is
equally dominating in both the s.m.l. and
the x.s.l. zone. Ramalina siliquosa was
found in the m.s.l. zone at loc. 59, but not
in the x.s.l. zone. Rhizocarpon constrictum
has never been reported in the Faroe
Islands.
The zones are 2 m wide in both localities,
and the only usable indicator here is Anapt-
ychia fusca.
5.6 The terrestrial region.
On the terrestrial region the seaShore
zonation stops, and the terrestrial lichen
species become dominating. The first
phanerograms which invade are Armeria
maritima, Festuca rubra, and Cochlearia
officinalis.
The colour of the first part of this zone is
greyish white, which is due to the domi-
nance of Lecanora atra, Ochrolechia par-
ella and O. tartarea. Among these we find
Anaptychia fusca, small thalli of Caloplaca
marina and C. thallincola, larger thalli of
Caloplaca festiva and Aspicilia casiociner-
ia, until the terrestrial species become
dominating. Among the terrestrial species
which were found, Parmelia glabratula, F'.
sulcata, P. omphalodes, Lecanora muralis,
L. intricata, L. polytropha, and Lecidea
confluens can be mentioned.
The terrestrial species are those that
have their main distribution in the inland
area, and they can be catagorized as halo-
philic and halophobic respectively. The
halophilic species are those which tolerate
the seawater, e.g. Caloplaca festiva, Par-
melia saxatilis, P. sulcata, and Ramalina
subfarinacea. The halophobic species often
live in crevices and thus are protected from
the seawater. Parmelia omphalodes and
Huilia macrocarpa belong to this group.
6. The Influence of Guano.
The composition of the seashore lichens
is affected by the rich seabirdlife of the Far-
oe Islands. This is illustrated in tab. 4.
Most of the dominating species are ornito-
coprophilous and a smaller part is ornito-
coprophobic. Typical birdtops on the sea-
shore are dominated by following species:
Xanthoria parietina, X. candelaria, Anap-
tychia fusca, Physcia caesia, and Candela-
riella vitellina. On the vertical sides on such
birdstones we often find Ramalina sili-
quosa and other Ramalina species, that are
a little to moderate ornitocoprophilous.
The e.l. and l.f. zone are both dominated
by ornitocoprophobic species such as
Verrucaria maura, V. mucosa Caloplaca
marina, and C. thallincola. As these zones
are submerged regulary by the seawater,
these two zones are not the ideal landing
places for seabirds.
The m.s.l. and the s.s.l. zone has a grey-
ish character. The grey colour is due to the
ornitocoprophilus lichen Lechanora pol-
iophaea. In other places in Northern Eur-
ope this belt is dominated by the less orni-
tocoprophilous species Lecanora helicopis
and L. actophila. These two species seem to
be rare in the Faroe Islands. At loc. 59 the