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Mediterranean ecosystemsDistributionClimateSoilsVegetation typesEcophysiologyFire ecologyThe “Ruined Landscape” hypothesis
Mediterranean landscape I
Mediterranean landscape II
Mediterranean and mediterraneoid ecosystems
Only 2% of land area but ~20% of plant species;30° - 35° latitude; west side of continents
Plant communities, El Torcal, Andalucia,
Spain(photos: Ian Hutchinson,
June, 2007)
Medit
err
anean c
limate
s
H
H
HH
H
July
Mean ann. range (°C) 10° 16° 19°
H
H
HH
H
JanuaryM
edit
err
anean c
limate
s
Mediterranean soils(terra rossa)
A Thin mull humus forming in eroded remains of Bt horizonBtf Illuvial horizon enriched with clay and iron, has become red-coloured. High clay content renders them relatively impermeable and prone to erosion
C Parent material (commonly calcareous) but in this case composed of Palaeozoic shales
Mediterranean Basin ecosystems
Type Weeks Soil Vegetationof drought
Humid <6 Alfi/Luvisols beech-deciduousoak-pine
Subhumid 6-10 Nitosols evergreen oak- pine
Semiarid 10-25 Non-calcic desert grasslandsbrowns
Arid >25 Aridisols desert
*
Elevation - vegetation relations (e.g. southern Italy)Elev.
(m)
400
1500
Mediterranean(=subhumid)
sub-Mediterranean(=humid)
beech -oak forest
deciduous oak - pine forest
evergreen oak - pinewoodland
800
0
semiarid grassland - macchia
Mediterranean(=semiarid)
Montane pine forest, central Corsica
Evergreen oak forest, Mt Athos, N. Greece
A monastic “temple” for over 1000 years
Water acquisition
The Mediterranean as a “lost Eden”
Mediterranean vegetation: degradation to two endpoints?
Oakwoods
maquis
semi-phrygana semi-desert
phrygana
Based on Pantis, J.D. and Mardiris, T.A. 1992. Israel J. Bot., 41, 233-242 [Fig. 2]
maquis-phrygana mosaic (Crete)
Grazing intensity
Goats at farmhouse near Antequera, Andalucia, Spain. (June 2007; photo: Dave Napthali)
Grazing and fire effects on Mediterranean vegetation
Data: Pantis, J.D. and Mardiris, T.A. 1992. Israel J. Bot., 41, 233-242 [Table 3]
Lowland pastures (Thessaly, Central Greece)
0
20
40
60
80
100
1 2 3 4 5
Vegetation association
% p
lan
t co
ver
herbaceous
woody
1. Oak woodland (Quercus coccifera)
2. Maquis (Q. coccifera-Thymus capitatus)
3. Phrygana (T. capitatus - Ballota acetabulosa)
4. Phrygana? (T. capitatus - Asphodelus aestivus)
5. Geophyte semi-desert(A. aestivus )
Vegetation association (dominants)
Grazing and fire effects on Mediterranean vegetation -
palatabilityLowland pastures (Thessaly, Central Greece)
0
20
40
60
80
100
1 2 3 4 5
Vegetation association
% p
lan
t co
ver
undesirableless desirabledesirable
Data: Pantis, J.D. and Mardiris, T.A. 1992. Israel J. Bot., 41, 233-242 [Table 3]
Palatability according to
local shepherds
Deforestation in the Middle East and Mediterranean world: the legacy of
Gilgamesh
The Epic of Gilgamesh, dating from about 2700 BC, celebrates the life of the legendary Babylonian king. On the 5th clay tablet, Gilgamesh and his friend Enkidu (a former “wild-man”) travel for 7 days to confront the demon Humbaba, the guardian of the great Cedar Forest. After an epic battle, Humbaba is killed. Then:“they attacked the cedars - and while Gilgamesh felled the first of the trees of the forest Enkidu cleared their roots as far as the banks of the Euphrates”.
After having felled the forest the heroes return on a cedar raft and use the tallest of the cedars to build a gate for the city of Uruk.
The legacy of Gilgamesh
Deforestation resulted from:• Wood consumption for fuel (~90% of
total?) to supply domestic hearths, baths and industrial activities; shipbuilding, and military activities. Urban centres, metallurgical refineries and potteries placed a heavy demand on local fuel (charcoal) supply.
Deforestation in Cyprus
Copper ores in Cyprus heavily exploited in Roman times, but mines functioned for about a millenium. Estimated that 5-6 M tons of charcoal (from coppice) used to fuel smelting activities. Heavy SO2
pollution may also have killed trees.
The legacy of GilgameshDeforestation resulted from:• Agricultural clearance - trees uprooted
and burned down. Ashes used for fertilizer.
• Pasturage - herdsmen cut branches to feed cattle and cut down trees to improve pasture for cattle and sheep. Pigs eat tree seeds, goats browse on young trees - combined effect is permanent deforestation
Early anthropogenic deforestation in the eastern
Mediterranean
Jerf-el-Ahmar archaeological site
N. Syria;~11,600 years old
Defo
rest
ati
on in t
he
Ghab v
alle
y, N
W S
yri
a pines
ced
ar
deci
du
ous
oaks
everg
reen
oaks
oliv
e
9970±100
12890±160Quat. Inter.73/74, 127-
Clearance at Sögöt, S.Turkey
Clearance of oak woodlands for
pasture, subsistence
agriculture and arboriculture
above: subsistence farming (Andalucia)left: Olives (Jaen)
Photos: Dave Napthali,June 2007
Initiation of land degradation in the Mediterranean basin
Goudie, A. 1992. Environmental Change. Oxford
The effects of deforestation
“what now remains compared with what then existed is like the skeleton of a sick man, all the fat and soft earth having wasted away, and only the bare framework of the land being left”
Critias 111B
On the landscape of Attica (central Greece), Plato commented:
Holo
cene v
alle
y fi
lls in G
reece
North South
Are these episodes of erosion associated with phases of climate change, or are they exclusively anthropogenic?
Soil erosion and valley filling:
e.g. Ephesus, W. Turkey
"Big fires are a predictable result of rural depopulation, land abandonment, increase of wild vegetation, modern forestry, legislation against fire, and the growth of a fire-fighting industry."
Rackham, O. 2003. Fire in the European Mediterranean. Aridlands Newsletter, No. 54, November/December
Deserted village and invading pines,western Crete (photo: Oliver Rackham, 1989)
0
5
10
15
20
1850 1900 1950 2000
Pop
ula
tion
den
sit
y (
/km
^2
)
Rural depopulation, mountains of Aragon, Spain.
(data: Collantes, F., Pinilla, V. 2005. Rural History, 15, 149-166.)