Fróðskaparrit - 01.01.2002, Page 125

SOPPARÓT í FØROYSKUM FJALLAVØKSTRI
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Alchemilla filicaulis
Alchemilla faroensis
Deschampsia alpina
Epilobium lactiflorum
Gnaphalium supina
Juncus triglumis
Luzula arcuata
Luzula multiflora ssp. multiflora
Poa glauca
Thalictrum alpinum
Table 1. Species probably arbuscular mycorrhizal.
phosphorus and nitrogen content were
measured (Fig. 1).
This mycorrhizal study has combined
the fíeld results with the checklist from
Harley and Harley (1987) and the Ecoflora-
database from the University of York (Fit-
ter and Peat, 1994) as the main source to
determine whether a plant species is myc-
orrhizal or not, and if it is mycorrhizal,
what type of mycorrhiza the plant is likely
to associate with.
The sum of frequencies of angiosperms
was 24,516. Ferns, lycopods, equisetum
and bryophytes are omitted from the
dataset.
Results
Of a total of 102 species the mycorrhizal
status was unknown for 25 species. Howev-
er, by looking at relatives, some of these
species are estimated as probably arbuscu-
lar (Table 1) or probably non-mycorrhizal
(Table 2). The group with no mycorrhizal
record (Table 3) now consist of 6 species,
and accounts for 0.3% of the total plant fre-
quency.
In this study the number of plant species
which form ericoid mycorrhiza is higher
Cardaminopsis petraea
Cerastium nigrescens
Cochlearia ojficinalis
Euphrasia arctica
Euphrasia frigida
Euphrasia micrantha
Euplirasia scottica
Koenigia islandica
Rhinanthus minor
Table 2. Species probably non-mycorrhizal.
Ranunculus glacialis Rliodiola rosea Saxifraga hyperborea Saxifraga hypnoides Saxifraga rosacea Sedum villosum
Table 3. Species with no mycorrhizal record.
than the number ol' plant species which are
likely to form ecto-mycorrhiza. However,
when considering the frequency, the ecto-
mycorrhizal plant species occur twice as
frequently in the survey (Table 4). In con-
trast 17% of the species are non-mycor-
rhizal, but non-mycorrhizal plants account
for less than 7% of the total sum of fre-
quencies.
% of total plant species % of total plant frequency
Ericoid 2.9 6.8
Ecto 2.0 12.9
Orchid 2.0 0.3
Arbuscular 69.6 73.0
Non-mycorrhizal 16.7 6.7
Table 4. The distríbution ofplant species grouped
after their mycorrhizal status. First column shows
how the mycorrhizal types are distributed based on
the number of plant species invoived. The second
column shows how the mycorrhizal types are
distributed based upon the sum of frequencies.