Fróðskaparrit - 01.01.1968, Síða 116

124
Gróðrarleivdir (sáð) av dvørgabjørk
bjørik enn fura. SoleiSis er tað eisini við heilt ungum tilfari,
har vit vita, at alt træsáð er borið langvegis frá.
Hin knappligi vøksturin og hin knappliga mmkingin av
bjørkini vísa eisini, at sáðið kemur nærhendis frá.
Ein C 14 tíðarfesting eitt sindur longur uppi enn tað dýpið,
her er kannað, vísir, at sáðstrikumyndin fatar um tíðina
seinast Preboreal — fyrst Boreal. Farstrikurnar av Ulmus og
Corylus benda á somu leið.
A pollendiagram from the Faroe Islands
showing former presence of Betula nana
Introduction. The Geological Survey of Denmark (D.G.U.)
has taken up systematic studies on the vegetational history
of the Faroe Islands. This paper gives one of tíhe first results,
namely the fact that Betula nana, which to day is absent from
the islands — as all otíher birches — has been growing thare
earlier. At Hoydalar, Streymoy, a boring ihas been made and
analyses of the lowermost samples in tihe profile have clearly
proved the existence of Betula nana.
As the problem of birch in tíhe Faroes has been discussed
earlier, and as it ihas been searched for witíhout success, a
publication of this diagram may be of interest though it only
covers tíhe lowermost part of a much larger profile. The rest
of tíhe diagram will be published later.
Locality. Tihe locality is a forrner lake wihiah has been filled
up, located at Hoydalar, north of Tórshavn, fig. 1. It is an
almost circular depression — diameter ca. 200 m — in the
basalt rock, caused by glacial overdeepening. The site is close
to the sea and situated 12 m above sealevel. The depth of the
sediment is 702 om. The uppermost 4 m consist of peat and
the lowermost 3 m of diatom gyttja.