Fróðskaparrit - 31.12.2000, Blaðsíða 38

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A REVIEW OF PLANT COMMUNITIES OF THE FAROE ISLANDS
edition with new records in 1952. In order
to get more accurate information on fre-
quency and distribution of vascular plants,
a comprehensive field study was made in
1960-1961. These investigations also gave
information about the zonation of the vege-
tation in the Faroe Islands, and the native
and introduced plants with regards to their
taxonomy, distribution and ecology
(Hansen, 1964; 1966; 1972). In 2000, a
new flora from the Faroe Islands (Jóhansen,
2000) and an updated overview of the dis-
tribution of vascular plants (Fosaa, 2000)
were published.
Ostenfeld (1906; 1905-1908) made the
first investigation of Faroese plant commu-
nities. He gave a comprehensive descrip-
tion of plant communities throughout the
islands. He also studied human influence
on the vegetation, phenology, functional as-
pects (Raunkiær life form system), and the
altitudinal distribution of species. Bócher
(1937; 1940) made later studies of plant
communities in which he described the
alpine vegetation - especially fell-fields,
Racomitrium heaths, snow-bed vegetation,
and other types of mountain vegetation. He
also studied the heath land flora and its
phytogeographical affinities. The phyto-
geography of the Faroese flora was also
studied by Jensen (1901), Warming (1888),
and Tukhanen (1987). Rasmussen (1946)
studied the effect of guano on plants on bird
cliffs. Later investigations of plant commu-
nities were made by Hansen (1967), Tom-
linson (1981), Dierssen (1982; 1996),
Hobbs and Averis (1991), and Tannhauser
(1995).
In the present paper, a review is given of
what is known about the plant communities
in the Faroe Islands. Only publications
with comprehensive descriptions of plant
communities and publications using quan-
titative methods to sample the vegetation
are considered here.
Summary of the Geology,
Climate, and Soil Types
The Faroe Islands is a treeless archipelago
situated between 61°20’ and 62°24’ N and
between 6°15’ and 7°41’ W in the warm
North Atlantic Current. The nearest neigh-
bour, the Shetland Islands, is 345 km to the
southeast. The Faroe Islands consists of 18
islands separated by narrow sounds with a
total land area of 1,400 km2. The distance
from north to south is 113 km and from east
to west is 75 km. The highest mountain
peak is 882 m a.s.l. During the last ice age,
the Faroe Islands was covered with its own
ice cap, distinct from the ice cap covering
continental northern Europe. Possibly only
the highest mountain peaks protruded from
the ice, forming nunataks. These nunataks
are thought to be refugia for some arctic
plants, which were able to survive there.
The majority of the present plant species
invaded the islands after the ice disap-
peared about 10,000 years ago through the
action of wind, ocean currents, birds, and
later, by man.
The Faroe Islands was formed by vol-
canic activity during the Tertiary, about 50-
60 million years ago. From a geological
point of view, the islands belong to the
North Atlantic Basalt Area. Part of this
area occurs in north-east Ireland, the west
coast of Scotland, in south-east and north-