Mediterranean ecosystems

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Mediterranean ecosystems

• Distribution
• Climate
• Soils
• Vegetation types
• Ecophysiology
• Fire ecology
• The Ruined Landscape hypothesis

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Mediterranean landscape I
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Mediterranean landscape II
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Mediterranean and mediterraneoid ecosystems
Only 2 of land area but 20 of plant
species 30 - 35 latitude west side of
continents
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Plant communities, El Torcal, Andalucia,
Spain(photos Ian Hutchinson, June, 2007)
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Mediterranean climates
Mean ann. range (C) 10
16 19
July
7
January
Mediterranean climates
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Mediterranean Basin precipitation
Feb. July
mm/day
Source CLIVAR Africa
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Mediterranean soils(terra rossa)
A Thin mull humus forming in eroded
remains of Bt horizon Btf 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
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Mediterranean Basin ecosystems
Type Weeks Soil Vegetation of
drought Humid lt6 Alfi/Luvisols
beech-deciduous oak-pine Subhumid 6-10 Nitos
ols evergreen oak - pine Semiarid 10-25 Non-
calcic desert grasslands browns Arid gt25 Ari
disols desert

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Elevation - vegetation relations (e.g. southern
Italy)
Elev. (m)
beech - oak forest
sub-Mediterranean (humid)
1500
deciduous oak - pine forest
800
Mediterranean (subhumid)
evergreen oak - pine woodland
400
semiarid grassland - macchia
Mediterranean (semiarid)
0
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Montane pine forest, central Corsica
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Evergreen oak forest, Mt Athos, N. Greece
A monastic templos for over 1000 years
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Vegetation - climate relations, California
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Vegetation - topography relations, California
N-facing
S-facing
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Common plants of the chaparral
2
3
1
1. Adenostoma fasciculatum 2. Heteromeles
arbutifolia 3. Ceanothus verrucosus 4. Quercus
dumosa 5. Cneroridium dumosum
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5
Dumos a bramble
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Chaparral/maquis plants

• Common features
• microphylly (small leaves)
• sclerophylly ( hard leathery leaves with waxy
  surfaces)
• aromatic foliage (herbs and spices)
• woody stems
• deep root systems

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Plant seasonality
rainfall
drought
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Water acquisition
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Water conservation strategies
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Sclerophyll leaf anatomy
upper
1 2 3
A B C
lower
1. Cutinized upper surface 2. Stomates in
crypts 3. Tomentose openings to crypts
A Ceanothus gloriosus CA B Banksia marginata
Aus. A Nerium oleander Med.
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Plants of the coastal sage (CA)
2
1. Salvia apiana (white sage) 2. Salvia mellifera
(black sage)
1
1
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Plant tactics allelopathy

• Hypothesis that plants suppress competitors and
  reduce herbivore attacks by production of
  noxious chemicals ( e.g. aromatic foliage of
  Salvia or oil-rich leaves of Eucalyptus which
  produce intense fires, kill competition)
• Bare zone and inhibited grass growth around
• Salvia patches in Santa Inez Valley,
  California

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Post-disturbance succession or climax communities?
maquis Fr. matorral Sp.,Ch. macchia
It. chaparral Ca.
garrigue Fr. phrygana Gr. coastal sage
Ca. mallee (Aus.)
evergreen oak - pine woodland
Sclerophyllous woodland with broad-leaved
deciduous trees along streams. Trees lt30 m
Sclerophyllous shrubland small trees lt8 m high
often dense
Sclerophyllous shrubland small shrubs lt1 m high
Increasing disturbance?
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Vegetation - climate relations, California
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Community- environment interactions in shrublands
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Thick litter buildup in mature chaparral
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Wildfire in the chapparral
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Burnt chaparral
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Post-fire soil erosione.g. sediment yield after
1989 Mt. Carmel CA forest fire
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Fire and slope stability in southern California
chaparral links to the ENSO cycle
El Niño La Niña La Niña
normal (winter) (winter)
(summer) (winter)
slides and mudflows
hydrophobic layer
e.g. 1997-8 1998-9
1999 1999-2000
in the summer of 1999 x2 average acreage
burned in southern California
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Post-fire recovery
The majority of maquis and chaparral shrubs are
capable of resprouting after fire (e.g.
California lilac Ceanothus tomentosus) . Fire
reduces competition (by removing alleopathic
litter) and opens up the canopy to allow
germination of fire annuals.
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Post-fire succession in chaparral
shrubs
perennial
Number of plants 5m2
fire annuals
data from S. California fire annuals are rare
in Med. areas (e.g. Chile) with long fire
recurrence intervals
yrs
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The Mediterranean as a lost Eden
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Mediterranean vegetation degradation to two
endpoints?
gtgtgt Fire frequency gtgtgt
Oak woods maquis
semi-phrygana semi-desert phrygana

gtgt Grazing intensity gtgt
Based on Pantis, J.D. and Mardiris, T.A. 1992.
Israel J. Bot., 41, 233-242 Fig. 2
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maquis-phrygana mosaic (Crete)
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Grazing intensity
Goats at farmhouse near Antequera, Andalucia,
Spain. (June 2007 photo Dave Napthali)
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Grazing and fire effects on Mediterranean
vegetation
Vegetation association (dominants)

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 )

Data Pantis, J.D. and Mardiris, T.A. 1992.
Israel J. Bot., 41, 233-242 Table 3
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Grazing and fire effects on Mediterranean
vegetation - palatability
Palatability according to local shepherds
Data Pantis, J.D. and Mardiris, T.A. 1992.
Israel J. Bot., 41, 233-242 Table 3
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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.

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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.

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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.
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The legacy of Gilgamesh

• Deforestation 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

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Early anthropogenic deforestation in the eastern
Mediterranean
Jerf-el-Ahmar archaeological site N.
Syria 11,600 years old
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Deforestation in the Ghab valley, NW Syria
pines
deciduous oaks
cedar
evergreen oaks
olive
9970100
Quat. Inter. 73/74, 127-
12890160
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(No Transcript)
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Clearance at Sögöt, S.Turkey
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Clearance of oak woodlands for pasture,
subsistence agriculture and arboriculture
above subsistence farming (Andalucia) left
Olives (Jaen) Photos Dave Napthali, June 2007
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Initiation of land degradation in the
Mediterranean basin
Goudie, A. 1992. Environmental Change. Oxford
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The effects of deforestation
On the landscape of Attica (central Greece),
Plato commented
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
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Holocene valley fills in Greece
South
North
Are these episodes of erosion associated with
phases of climate change, or are they exclusively
anthropogenic?
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Soil erosion and valley fillinge.g. Ephesus, W.
Turkey
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A heretical viewpoint Grove and Rackham
some of their interpretations are "heretical"
and not shared by many of their ..research
colleagues. These include the notion that
there is little if any desertification going on
in (Mediterranean) Europe that Mediterranean
Europe's badlands and most of its erosion is
natural and not the result of human action (here
they endorse Vita-Finzi's ideas) that the human
shaping of the landscape of Mediterranean Europe
was for the most part complete by the Bronze Age,
and that human agency has not done much to change
it since-until perhaps the last thirty years when
bulldozers have been let loose. Abstracted from
the review by J. R. McNeill, 2001. Environmental
History, October issue.
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Rural depopulation, mountains of Aragon,
Spain.(data Collantes, F., Pinilla, V. 2005.
Rural History, 15, 149-166.)
Deserted village and invading pines,western
Crete (photo Oliver Rackham, 1989)
"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