Rit (Vísindafélag Íslendinga) - 01.06.1975, Blaðsíða 137

on analyses 3-4 which are in fact not made on elevations or ridges,
but in the driest areas of the strip.
Table M shows observations which are conducted in a manner
which departs from the normal procedure used in this research.
There we see the conclusion of a study made at Möðruvellir in
Hörgárdalur. This is a wet flæðimýri which was in fact often har-
vested in earlier times, but cows also used to graze there. As before,
C. Lyngbyei is predominant here, but the species are generally
somewhat more numerous than at Hvanneyri. Calamagrostis neg-
lecta maintains a high constant, 80%, but its covering is insignifi-
caní, 1-2 (Hult-Sernander scale). Two notable species occur here,
which were absent at Hvanneyri, Equisetum fluviatile and Com-
arum palustre.
Analyses Tab. XVII 1—7 are from different parts of the coun-
try. 1-3 are from Ketilsstaðir in Jökulsárhlíð, 5 is from Miðhús
in Mýrar and the others are from Vestur-Landeyjar. The species
here are mostly the same as in the other areas, but somewhat more
numerous in some analyses. An additional species occurs which
is practically constant. This is Equisetum palustre which clearly
mdicates a closer affinity to sociation 79. Analyses 1-3 are all from
old alluvial terrain which in many places resembles flói. I have
made one analysis in this area which I classify as C. Lyngbyei —
C. rariflora — C. chordorrhiza flói Tab. Vx3). From the close af-
finity of these sociations and their adjacent location it may be de-
duced that the area begins to change into flói when the lakes which
formed the flæðimýri begin to ebb out with a resulting stagnation
°f the ground water. The same phenomenon was encountered in
Landeyjar where the C. Lyngbyei flói sociations dealt with in Tab.
Vx 1_2, 7-8 are from the same mire tract as analyses 4, 6-7 des-
cribed here. But all these vegetation analyses collectively present
a survey of the vegetation type in this part of Landeyjar. Analysis
Tab. Xx. 13 which shows a C. nigra — Equisetum palustre — C.
Lyngbyei sociation belongs to the same series of analyses, and
furthermore Tab. XVx. 1-2 which is an Equisetum palustre — C.
Tynghyei mire. These sociations coexist in a variety of ways. The
C. Lyngbyei flæðimýri occurs in the dampest areas and where the
Water is clearly in motion, but the others are found where the
terrain has risen and the ground water level has consequently
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