Rit Landbúnaðardeildar : A-flokkur - 01.10.1967, Page 40

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into 52 plant associations (see Appendix), 38 on well-drained and 14 on
poorly-drained soils. The plant associations and the area covered by each
in the separate commons are shown in Tables 4, 6 and 8, while a com-
parison of the vegetation of the commons is shown in Table 9.
Moss heath covers 40—50 per cent of the total vegetated area and is
dominating at the upper limits of vegetation. At lower elevations on
well-drained soils various species of dwarf shrubs and sedges gradually
become dominating. Wetland vegetation is quite extensive.
Plant associations dominated by plant species most palatable for sheep
(grasses, forbs and some dryland sedges) cover only 2 per cent of the
total vegetated area. There is reason to think that this is to a great extent
the result of prolonged overgrazing and that the present vegetation only
partly represents climax vegetation.
The grazing value of the various plant associations is graded with a
scale of 0-10. The grazing capacity of each common is expressed in
„grazing units“ which are obtained my multiplying the grade of each
association with its total area. These values are shown in Table 8.
The average value for each common, that is the number of grazing
units per hectare of vegetated land, coincide as a grazing value of 3 which
shows their poor quality for the grazing of sheep.
VIÐAUKI
APPENDIX
ÞURRLENDI
Freely drained land
Aji Mosaþemba Rhacomitrium heath
A„ Mosaþemba með stinnastör Rhacomitrium heath with Carex Bigelowii
A;1 Mosaþemba með Stinnastör og smárunnum Rhacomitrium heath with Carex
Bigelowii and dwarf shrubs
A4 Mosaþemba með smárunnum Rhacomitrium heath with dwarf shrubs
A_ Mosaþemba með grösum Rhacomitrium heath with Graminae
A6 Mosaþemba með þursaskeggi Rhacomitrium heath with Kobresia myosuroides
A_ Mosaþemba með þursaskeggi og smárunnum Rhacomitrium heath with Kobre-
sia myosuroides and dwarf shrubs
As Mosaþemba með grösum og smárunnum Rhacomitrium heath with Graminae
and dwarf shrubs
B4 Krækilyng - f jalldrapi - bláberjalyng Empetrum hermafroditum - Betula nana-
- Vaccinium uliginosum
B„ Krækilyng - bláberjalyng - sauðamergur Empetrum hermafroditum - Vaccinium
uliginosum - Loiseleuria procumbens