Fróðskaparrit - 01.01.1999, Blaðsíða 187

HVUSSU DJÓRASLØG í FØROYSKUM FIRÐUM LAGA SEG EFTIR ALDUBROTUM
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Exposed
Biological exposure grade 0 1 2 3
Aglaothamnion sepositum 65 55 50 40
Alaria esculenta 65 70 65 65
Ascophyllum nodosum 0 0 0 0
Cladophora rupestris 0 0 0 0
Corallina officinalis 65 60 55 50
Fucus distichus f. anceps 70 25 0 0
Himanthalia elongata 55 50 40 30
Mastocarpus stellatus 50 50 45 40
Pelvetia canaliculata 0 0 0 0
Polysiphonia stricta 65 55 50 40
Porphyra umbilicalis 60 65 65 65
Verrucaria mucosa 0 0 0 5
Littorina obtusata 0 0 0 0
Nucella lapillus 0 5 10 15
Semibalanus balanoides 50 60 60 65
Sheltered
4 5 6 7 8 9 P R2
30 20 10 0 0 0 *** 0,759
55 50 35 25 5 0 *** 0,775
0 0 0 0 35 70 * 0,017
0 0 0 10 25 40 *** 0,836
45 40 35 30 25 20 *** 0,557
0 0 0 0 0 0 *** 0,940
20 10 5 0 0 0 *** 0,679
40 35 35 30 30 25 *** 0,325
0 0 0 0 10 25 ** 0,442
35 25 15 10 0 0 *** 0,876
60 55 45 35 20 5 *** 0,846
10 15 20 25 30 35 *** 0,386
0 0 0 15 30 50 *** 0,790
20 25 30 35 45 50 *** 0,632
65 65 65 60 55 50 *** 0,350
Table 3. Abundance valuefor each ofthe 15 dominant species at different biological exposure values (BEV).
P = level of significance; *** < 0.001; ** < 0.01; * < 0.1, R2 = coefficient of determination.
Talva 3. Nøgdarstig fyri hvørt av teimum 15 sløgunum, sum mest var til av, í mun til lívfrøðiliga stigan,
ið er gjørdur í mun til styrki av aldubrotum (BEV). P = signifikansur. *** < 0.001, ** < 0.01, * < 0.1.
R2 = ásetingarstuðul
the total explained variance in the CCA
analyses was less than 25%. Examples of
such factors that may have increased vari-
ance in our data include the local influence
of rainwater, heterogeneous texture of the
substrate, and biological interactions.
The biological exposure scale is relative
and directly applicable only to the area
where it was developed, although some
cautious comparisons can be made with
other areas. Species polynomials have
been established with the same method for
several areas of the Norwegian coast (Dal-
by et al., 1978; Árrestad and Lein, 1993;
Kruskopf and Lein, 1997). In the Norwe-
gian studies, some species showed slightly
different distribution pattems from one area
to another, i.e., some showed a gradient
from south to north. Compared to the west-
em coast of Norway, Sogn and Ljordane
County (Kmskopf and Lein, 1997), the re-
sponse polynomials developed for the
Laroe Islands were similar for Corallina of-
ficinalis and Verrucaria mucosa, whereas,
they were slightly different for other
species. Alaria esculenta, Mastocarpus
stellatus, Ceramium schuttleworthianum,
Aglaothamnion sepositum, and to a lesser
degree, Himanthalia elongata seemed to
grow in more sheltered sites in the Laroe Is-
lands than in Sogn and Ljordane. Price and
Lamham (1982) made similar observations
when comparisons were made with English
shores.
The climate of the Faroe Islands is strict-
ly oceanic with little difference in winter
and summer temperatures and high humid-
ity caused by frequent rain and fog. There-
fore, the effect of desiccation on littoral al-
gae is less profound than in areas further