Environmental Engineering Reference
In-Depth Information
climatic variations, especially temperature. Naturally there are many variations be-
tween mountains (due to geology, altitude and human history), with some moun-
tains supporting unique communities/assemblages. The (upper) Montane Mediter-
ranean zone is dominated either by beech or conifers, including pines, cedars and
firs. In the Taurus mountains between 1200 and 2000 m,
Pinus nigra
ssp.
palas-
siana
forests are found, which are often associated with
Cedrus libani
and
Abies
cilicica
(Kaya and Raynal, 2001).
Cedrus libani
forests are confined to the high-
est zones of the eastern Mediterranean, reaching about 2200 m. Some of the best
examples are seen in the Lebanon Mountains, while less extensive and often relict
stands can be found in Syria and the Amanus and Taurus Mountains. Above 1000 m
in the Troodos mountains of Cyprus there are stands of the endemic Cyprus cedar
Cedrus libani
ssp.
brevifolia
as well as
Juniperus foetidissima
above 1600 m (Tsin-
tides
et al.,
2002).
Juniperus excelsa
and
J. foetidissima
forests are also common in
the Taurus Mountains particularly in places where cedar and pine forest have been
degraded (Kaya and Raynal, 2001). In the High Atlas of Morocco there are
Cedrus
atlantica
relict stands, while in the mountains of Crete and Sicily the endemics
Zelkova abelicea
and
Zelkova sicula
are respectively present. In the Levantine up-
lands
Quercus calliprinos
forest and scrub,
Abies cilicica
forest and
Cedrus libani
forest occur. In Corsica a sharp north-south gradient in terms of plant communities
typifies the highest elevations of this zone.
Pinus laricio
dominates on south-facing
slopes while silver fir (Abies alba) and beech (
Fagus sylvatica
) are dominant on the
north-facing slopes (Mouillot
et al.,
2008).
Nagy and Grabherr (2009) discuss the difficulty in delineating the treeline in the
European Mediterranean due to the absence of trees and their replacement by thorny
shrubs. The treeline-forming trees in the Mediterranean mountains include
Pinus
heldreichii
in the Hellenids,
Cupressus sempervirens
in Crete,
Juniperus communis
ssp
. hemisphaerica
in the Sierra Nevada and
Juniperus excelsa
in the Atlas Moun-
tains (Figure 6.2). In Greece the timberline lies at c. 1800 m, a criterion used to
delineate the country's mountain flora (Strid, 1986). However, in the highest Greek
mountain, Olympus, the treeline reaches 2300 m. In the High Atlas the treeline lies
at approximately 2400 m, formed by
Juniperus excelsa
and
Juniperus foetidissima
,
while in the Hellenids this role is played by
Pinus heldreichii
and in the Taurus by
Juniperus thurifera
(Nagy and Grabherr 2009). In the Lefka Ori of Crete the upper
limit of forest growth on the southern side of the massif is at 1600-1650 m, while
on the northern side the limit is up to 150 m higher. This limit is significantly lower
compared to more extensive mountain ranges such as the Alps, where the limit rises
to 2400 m. (Turland
et al.,
1993).
The zones above the treeline are rich in perennial but poor in annual species.
The alti-Mediterranean zone usually includes dwarf junipers mixed with diverse
grass communities of
Bromus
,
Festuca
,
Poa
,
Phleum
and other perennial species
(Blondel
et al.,
2010). In Corsica, for example, the high summits are character-
ized by the dominance of dwarf shrub alder, juniper and maple (Moullot
et al.,
2008) whereas the corresponding zone in the Sierra Nevada has open dry grassland
with endemics such as
Eryngium glaciale
and
Festuca clementei.
The main veg-
etation formations covering the stony slopes of the highest mountain zones in the
