Transcript idrosfera e mar mediterraneo

Mare
nostrum
…in the middle of lands
•
The only natural link to oceans is constituted by the Gibraltar Strait, which
with its 15km of length and 400m of depth, is the only way of communication,
with the Atlantic ocean to the west .
• In the eastern sector it is instead linked, since 1869, to the Red
Sea, consequently to the Indian Ocean through the artificial Channel
of Suez (161 km)
Surface 2 560 000 km2 (included the Black Sea)
Lenght ( Gibraltar strait- Libanon coasts) around 3800 km
Average Depth 1429 m
Maximum Depth, in the Ionian sea, near Matapan cape, Peloponnesum, > 5000 m
Coast extension about 46.000 km
The amount of water coming back from rivers and rainfalls is less than
that which evaporates :
-110 000 m3/s +38000m3/s
with a sweet water deficit estimated of approximately 2.500 kilometers
cubes (km3) annually
If there was’nt the communication with Atlantic ocean The Mediterranean
would desappear in some ten thousand years!!
At 500m of depth waters have a temperature that is about 12- 13° C
Anyway the superficial strata present ample variations, which depend
on seasonal changes: You can have in fact average temperatures of 10
degrees in Jenuary to average temperatures of 25°C in July . At the
same time temperature varies from West to East.(15-21)
Even salinity is different on the various basins: it varies from 36 to 39
‰ according to the evaporation and the fluvial contribution.
In the Adriatic sea salinity can reach 33 ‰ . The Ionian sea ,on surface,
is more salted than Tirrenian sea.
Temperature and salinity differences between
Mediterranean waters and Atlantic waters
bring about a double current.
The Mediterranean
waters, denser and
heavier, flow in depth
and enter the Atlantic
through the Gibraltar
Strait,
whereas the ocean
waters get into the
Mediterranean flowing
on surface.
It has been calculated that for the total substitution of waters 7000 years
are required.!
• The population of the states which look at
the Mediterranean sea is about 450
millions of people.
• Moreover there is a remarkable touristic
presence equal to a third of mondial flow
seasonally concentrated on coastal areas
particularly on the North Western ones.
The coastal landscape is varied
An ancient map of
Mediterranean sea
Italy divides the Mediterranean sea in two basins ,the western one and the
Eastern one.
The Mediterranean is subdivided in a certain numbers of independent seas:
the Ligurian sea, the Tirrenian Sea and the Sardinia Sea;
The Eastern Mediterranean is divided in the Sicily Sea, the Ionian sea and
the Adriatic Sea..
Italian coasts stretches along 8500km, and no Italy place
is more than 230km away from the coast .
How Mediterranean changed
Tentative reconstruction of the Mediterranean
evolution for the period Oligocene-middle Miocene.
This evolutionary phase has been
characterised by a profound tectonic
reorganisation of both the western and
eastern Mediterranean regions, where the
Balearic and Pannonian basins opened
up. Extensional tectonics also occurred in
the Northern Aegean and Northwestern
Anatolian zones.
Tentative reconstruction of the Mediterranean evolution
since the late Miocene,
This period is characterised by a profound
reorganisation of the central and eastern
regions, which respectively led to the formation
of the Tyrrhenian and Aegean basins.
Symbols as in Fig.2. A) Late Miocene: G=Giudicarie trans-pressional fault system, NA, SA=Northern
and Southern Apennines, NWT=Northwestern Tyrrhenian, Pe=Pelagian zone, SF=Selli fault. B)
Late Pliocene: AE=Apulian escarpment, CR=Crete-Rhodes, CT=Central Tyrrhenian (MagnaghiVavilov basin), K=Kefallinia fault, I=Iblean-Ventura microplate, Me = Medina fault, NAF=North
Anatolian fault system, SCH=Sicily channel fault system, SE=Siracusa escarpment, SV=SchioVicenza Line, Ta=Taormina fault zone, WCB=Western Cretan basin. C) Present: Ca=Calabrian
wedge, ECA=External Calabrian Arc, ECB=Eastern Cretan basin, KI=Kithira trough, LP=Lybian
promontory, PS=Pliny and Strabo trenches, ST=Southern Tyrrhenian (Marsili basin), VH = VictorHensen fault, VR=Vrancea zone.
Calabrian and Tyrrhenian sea geological evolution
in the last 10 million years
In the same period the
Ionian sea and the
Adriatic sea were much
wider of the present
ones.
At the end of the Tortonian era, about 10 millions of years ago, the distribution of
emerged lands and seas in the area of the mediterranean was very different
from how it appears today.
In that period in fact the tirrenian sea didn’t exist yet and Calabria, the northern
part of Sicily, Sardinia and Corsica were joined together to form an only
continental plate
About 7 millions of
years ago, during the
Miocene, the
Sardinian-Corse block
began to fracture and
from the fractures of
the crust a great
quantity of basaltic lava
leaked out. The
fracture widened more
and more until forming
a deep tectonic hollow
which very soon was
invaded by waters from
the sea.
The Tirrenian sea had
begun to form, while
the eastern part of the
old clod, contituted by
the present Calabrian–
Peloritan block, got
away more and more
from the Sardinian
Corse block.
The Tirrenian sea continues its expansion still today:
the present centre of expansion is at about 150 km to the
west of the Calabrian Coast where the oceanic crust
continues forming in correspondence with the submarine
volcan of Marsili.
• The old expansion centres are instead represented by
the submarine volcans of Magnaghi and Vavilov to the
North West regarding Marsili.
•
• While at the West of Calabria the Tirrenian sea
was developing ,on its eastern edge, as well as
all over the edge of the Apennine, the ancient
and heavy oceanic crust, which made up the
sounding depth of the Ionian and Adriatic sea
began to go down slowly in the mantle.
• The sediments which were found on the depth
of the sea following the subduction process
piled up ones on the others to form huge
blankets of covering contributing to the
formation of the Apennine Chain.
marine plants
The sounding depths of the Mediterranean sea
are covered with Posidonia prairies.
posidonia oceanica
The flowering is instead index
of goodhealth for the
ecosystem
Reduction of posidonia
prairies is index of pollution
algae
Sea lettuce
(Ulva
lactuca)
Mermaid's cup (Acetabularia mediterranea)
The non native introduction of
species has influenced the
species which were naturally
present, sometimes with
remarkable impacts: the
tropical Caulerpa taxifolia
seaweed has had catastrophic
effects on the native
environment
Padina pavonia
The present variety of the species is correlated to the inquinameno
anthropic pollution. In the lagoon of Venice, for instancee in 1938 were
found 141 species of seaweed, 104 in 1962 and only 95 in 1987, and there are
so polluted Lagoon areas which render the presence of some species
•Reduction of Posidonian prairies
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Ligurian sea 20 %
Alicante (Spain) 52 %
Marseille (France) About 90 %
Tolone (France). Completely desappeared
Gabes Gulf (Tunisie) Completely desappeared
Industrial and civil pollution
Alteration of sedimentation due to drag-net fishing
Competition with Caulerpa
–
from: UNEP-RAC/SPA, 1997a.
sponges
Spongia officinalis
Axinella polypoides
A. verrucosa
Spongia agaricina,
some of them are interesting
from an economic point of view
Haliclona
mediterranea
Cnidaria
(polyp jellyfish corals anemones)
The name Cnidaria comes
from the Greek word
"cnidos", which means
stinging nettle.
Coral
Corallium rubrum
Anemone sulcata
They are represented by the
red coral (facies of Corallium
rubrum) and by gorgonians
(Eunicella cavolinii,
Paramuricea clavata).
Yellow gorgonian eunicella cavolinii
Cnidaria
In the Mediterranean sea it is very easy to find the sea lung Rhizostoma pulmo
.
It is the biggest jellyfish of
this sea, it reaches 5060cm of diameter, it has a
low itching power.
The presence of jellyfishes
is index of a good quality of
waters.
Cnidaria
Actinia carii sea tomato
Sea potato
Prayeries of actinia
Echinodermata (marine stars , sea urchin)
Linckia multifora
Echinodermata
Oloturia sea cocumber
Holothuria forskali)
Mollusca
Cuttlefish
Sepia officinalis
Octopus vulgaris
Todarodes sagittatus
Crustacaea ( shellfish)
Pink prawn
Parapenaeus longirostris
Lobster Palinurus elephas
Red prawn
Aristeus antennatus
Penaeus Kerathurus
Anphibia
Bufo bufo
Triturus italicus
Yila arborea
Rana esculenta (frog)
Carthilagineous fish
(shark)
Scyliorinus canicula
Blue shark
Prionace glauca
Eggs of S.canicula
The ramarkable depth of the Mediterranean sea allows
life to some great pelagic species of cetaceans
dolphins
The marine communities of
the Mediterranean are
characterized, as regards
the Atlantic ones, by a
greater number of species
but generally with smaller
individuals (Mediterranean
dwarfism).
MEDITERRANEAN CETACEANS
Common rorqual
Balaenoptera physalus
The immun-soppressive effects of
contaminating agents coming from
agriculture, industrial activities and
demographic increase can have
contributed to the decimation of
marine mammalians of the
Mediterranean.
Delphinus delphis
Some species are in danger
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(Caretta caretta )
tortoise
Nun seal (monachus monachus)
Marine protected areas in Italy
Owl Athene noctua
The scientific name of this
bird is that of the greek
goddess Athena .
A blue eyed owl was the
symbol of Athena as we can
see in the coins above
Factors that influence the Mediterranean
ecosystem
• The eutrophization and the pollution coming from
agriculture, from industrial activities, from tourism and
from demographic increase
The introduction of non native species through dregs ship
waters, fouling, importations and biological invasions
Fishing and excessive exploitation of biological resources.
.
La
Thegrande
great slowness
lentezza con
withlawhich
quale
avviene
mediterranean
il ricambio
water
delle
renewal
acque
del
happens
Mediterraneo
icreasaes
accentua
the pollution
il
problema
problem dell’inquinamento
It is favoured by the continous increase of
industrialization and antropization of its
coasts
Moreover the oil pipe lines, which
carry to Europe the oil from the
Sahara and the Middle East, run
through the Mediterranean.
25 % of mondial oil (about
350.000.000 tonn. annue) pass
trough Mediterranean sea
The greater dangers come from
the oil tankers
(incidents, washing..)
The pollution by domestic and
industial wastes is serious in
certain areas
• Environmentalist organizations have often denounced
the traffic and the deposit of hazardous wastes. –
radiactive scum and chemical pollutants– coming from
all Europe, in the Southern Mediterranean, above all
along the African coast, in the Lebanon but even in
Calabria.
(Jolly rosso ship)
The mucillage
• The mucilage is constituted by gelatinous heaps produced by
fitoplanctonic species (Seaweeds)) that float in the sea rendering it
not transparent, moreover, joining to the nets,They make fishing
possibility diminish, causing remarkable economic damages The
mucilage is constituted by polisaccaridi and other substances
secrete from seaweeds (diatomee...) in abnormal quantity. It is not
clear if the phenomenon is connected to the pollution of the sea.
Actually it existed also in pre-industrial age: scientific signallings
exist since 1729 and testimony in the ever existing dialectal names
(broma, brommo, sbrommo), all of which have the same root: from
the Greek bromos = fetid )
Coastal erosion
• It is a quite diffused phenomenon on Italian coasts due to
different causes:
• Rise of the sea level
• Sand removal from rivers and beaches
• Buildings on the beach without considering the natural
variation of the coastal line
The protection of the Mediterranean Sea from pollution is guaranteed
from the Convention of Barcelona of 16 February 1976, adopted
under the aegis of the Intergovernment Council of the Environmental
Program. It acclimatizes them of N.U. (UNEP) and in order to supply
one legal instrument for the performance of the Action Plan for the
Mediterranean (MAP) adopted in Barcelona in 1975. Such plan, in
the second version approved in 1995, provides objects which are not
limited to the single antipollution fight, and that is
- to guarantee a durable management of the natural marine and land
resources,
- to protect the marine atmosphere and the coastal zones preventing
pollution
as well as reducing and if possible eliminating the contributions of
polluting of whichever nature;
- to defend , to safeguard and to revalue sites and landscapes of
ecological or cultural interest;
- to strengthen solidarity among the coastal States of the
Mediterranean managing their ir common patrimony and their
resources as an advantage for present and future generations;
- to contribute to the improvement of life quality.
Fishing
•
The main types of fishing
diffused in our seas are:
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drag-net fishing
pelagic fishing
mollusc fishing
small fishing
lagoon fishing
Type of fishing
The small fishing is the one
carried out by boats not bigger than 10
tons of gross tonnage. The dimensions
of the floating allow to be operated with
contained work and investment costs. It
is impossible to go further than 20 miles
from the coast and this let abilities of
fishing, of working, conservation and
stowage of the product beby no means
comparable to those of great boats. In
Italy this part of the fleet is of notable
importance.
There are 8,680 boats of small fishing (1997 are
available actually), that represent more than 53% of
the national flotilla.
Small fishing is particularly present in the Tyirrenian
sea with 2.083 boats and in the Adriatic with 1.640
boats. The tools employed for the small fishing are
above all position nets, bow-nets and palangari
The draw-net fishing is an
important activity in Italy.
Only the experience and a
deep knowledge of
sounding depths consent a
ready evaluation of tools
and maneuvers to be carried
out. The draw net fishing
can be carried out with
various types of tools that
vary in relation to local and
regional traditions. The
most used tools are the
draw-nets, the rapido, the
sfogliara.
This kind of fishing can be dangerous if done in
an uncontrolled way.
It menaces the existence of marine species that
lives in sounding depths
Many environmental associations have required
to stop this sort of fishing
Fish to be eaten fresh
SOLEA VULGARIS
SOLES, CODS...........
GADUS MORRHUA
MERLUCCIUS MERLUCCIUS
Diplodus vulgaris
Sparus aurata
Chromis chromis
Dicentrarchus Labrax -
Fish to be preserved
ENGRAULIS ENCRASICHOLUS
SARDINA PILCHARDUS
THUNNUS THYNNUS
To fishing in strict sense you can add
the collection and the cultivation of seafood
OSTREA EDULIS
CHAMELEA GALLINA
MYTILUS GALLOPROVINCIALIS
Sword fish
Xiphies gladius
´mattanza´
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The term ‘mattanza’(slaugther of tunny
fish) derives from the Spanish verb
matar to kill.
Tunny fishing happens in spring time
during the migration period of this
fish
Fishermen are divided in teams each
of them chooses a leader the “rais”
He has to individuate the palce from
whuch the tunnies will pass and
where they have to throw the nets
which make up the tunny fishing net
“tonnara“.
‘La tonnara’ or tunny fishing net is made up of
several nets in the waters before the port, spread
from the surface to the sea-bottom and set out in
such a way as to convey the tunnies towards a
net closed at its bottom, the net is said “chamber
of death”. Established the place, the tunning
fishing net is delimited holding some ropes to
water surface (the ‘tintole’) within which the net
that will stop the tunnies, will be thrown.
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The tunny fishermen ability is in
succedine to block the tunnies
that get into this barrage and in
making them flow, with the help of
various nets or chambers, up to
the final net called ‘chamber of
death’
When tunnies are trapped, the
fishermen boats encircle the
‘chamber of death); at the
command of the rais (the head of
fishermen), the "tonnaroti" (the
fishermen) begin to lift the net
that constitutes the base of the
chamber forcing the tunnies to
emerge on water surface.
At this point the tonnaroti 8tunny fishermen) pierce the tunnies with
long and sturdy iron hooks or harpoon and pull them into their boats;
then they will bring them to shore to be sold or processed.
Actually the catching of
hundreds of tunnies in a
few hours can’t be
anything but bloody, as
the big fishes, pressed
together in the final part
of the net island
(chamber of death), in a
as desperate as vane
struggle to escape and
survive, end to kill eah
other with strong tail
thrusts.
All around the sea is tinged with red and boils over due to the
dangerous tail blows given by the hooked tunnies while are being
loaded on boats.
The fishermen excitement reaches paroxism and the
show results to be suggestive but cruel, especially fo
those who are watching it for the first time.
T
The climate is temperate
mild influenced by warm air coming from the Sahara during
summer and by the more humid and cold air of the Atlantic
during winter.
Rainfalls are scarce and seasonal.
CLIMATE STATISTICS of Santa Maria di Leuca
Latitude 39.82N Longitude 18.35E Altitude 104m
Average data 1961-1990
The typical biome
is the Mediterranean flora
mainly characterized by shrubs or small evergeen trees
with coriaceous leaves ( sclerophilla )
able to stand summers with very high temperatures
and insufficient rainfalls.
Mediterranean flora:defence strategies
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Summery dryness causes strong stress for vegetable species
and, just in order to limit the damages that could be provoked by
excessive warmth and by water absence, the plants defend
themselves with several types of adaptation.
Some adaptation concern the morphology of the plant –
thickening of the foliaceous cuticle (sclerophillia),
reduction or disappearance of leaves (afillia),
presence of hair (hairiness) or thorns (thorniness) –
whereas other types involve physiology –
formation of underground organs (bulbs, tubers and rhizomes),
•
in which the plant limits its own vital activities protecting young
stems under the ground surface .
Another defensive strategy is the
reduction of the vital cycle (birth-life-death) of the plant in a very short period
Mediterranean typical species
Broom
(Spartium junceum, calicotome, ecc.),
Euphorbia (Euphorbia dendroides e characias),
Cistus
(Cistus incanus, salvifolius e monspeliensis),
Mastic
(Pistacia lentiscus),
Myrtle
(Myrtus communis),
Juniper
(Juniper phoenicius),
Rosemary (Rosmarinus officinalis),
Pine tree
Carob tree
Holmhoak
Dwarf palm
(Pinus pinea, halepensis, pinaster),
(Ceratonia siliqua),
(Quercus ilex), la roverella (Quercus pubescens).
(Chamaerops humilis
On the mediterranean sea spontaneously grow
(PANCRATIUM MARITIMUM)
TAMARIX GALLICA
T. AFRICANA
EUPHORBIA
EUPHORBIA POLYCROMA
EUPHORBIA HELIOSCOPIA
Euphorbia dendroides
Juniper (Juniperus phoenicius )
ARBUTUS UNEDO
Strawberry tree
myrtle
MYRTUS COMMUNIS
The butcher’s broom
Ruscus aculeatus
Cistus incanus,
C.salvifolius
C.monspeliensis
cistus
Cistus garrigue
Oleander
Nerium oleander
calluna vulgaris
Rosmarinus officinalis
rosemary
Acanthus mollis
bear's breech
Crataegus monogyna
hawthorn
Cetonia aurata
Heather
Erica arborea
broom
Calicotome villosa
spiny broom
Spartium junceum
Cytisus scoparius
scotch broom
Capparis spinosa caper
Calendule marigold
Cypripedium calceolus
Orchis italica
Lathirus odoratus
Oxalis acetosella
Erysimum cheiri
Violaciocca gialla
Rosa sempervirens
Allium triquetrum
Narcissus tazetta
Arecaceae
Chamaerops humilis L.
dwarf fan palm
The dwarf fan palm or Saint Peter’s palm
deserves a particular signal: it’s the only living
palm at a spontaneous state on continental
european coasts and one of the two,(the other
one is Phoenix theofrasti endemic to Crete
island) exclusively diffused in the
mediterranean basin
It is a living witness of a tropical type flora,
today completely disappeared, which from the
beginning of the Tertiary era (about 65 million
years ago) was diffused all over southern
Europe thanks to climatic conditions which
where completely different from the present
ones.
SweetBay Laurel Laurus nobilis
Fraxinus oxicarpa
Carrob (Ceratonia siliqua),
Pine trees
Pinus pinaster
pinus pinea
Calabrian
pine trees
Pinus nigra var.
laricina Calabria
Pinus leucodermis
OAK
q. ilex
(Quercus ilex)
(Q. suber)
( Q. pubescens)
q. pubescens
Fig
Almond prunus dulcis
ficus carica
Pistacia lentiscus
mastic
Pistacia vera
pistachio
Calabrian citrus
Bergamot citrus aurantum
Citron citrus medica
vine
The shrub which produces grapes, was
known in Sicily since 4000 years ago.
For a long time its cultivation was
confined in this area. Only after a
millennium it started to spread in the
rest of Italy.
Anyway it was thanks to the expansion of
the Roman Empire, about 300 B C, that
its cultivation spread all over the
Mediterranean and Europe.
With the discovery of America, new
species were introduced in the old
Continent which demonstrated to be able
to resist to a dreadful parasite, the
phylloxera, which attacked European
vines around the middle of 18oo BC.
Today Vine is cultivated in every
continent, over about 8million hectares,
the 60% of which in Europe.
The production is used for fresh
consumption and, the great part, to be
processed in wine.
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The vine – vitis vinifera- is a creeping shrub because its branches, said vine shoots,
clutch at walls or at appropriate supports thanks to tendrils, filiform formations coiledl
to external bodies in order to support the stalk.
It is well developed in limestone or silica lands and is rather demanding in fact of
brightness and heat, factors that are optimal in the hilly and well exposed zones. The
bloom will be in bunches, from which the grape-pip will develop.
Every single grape is particularly rich water berry, containing the grape-stones
inside, that is the seeds, rich of oleose substances. The grape-stones are protected
outside by a waxed veil, the bloom. that has the aspect of a light powder layer and
that make water to slip away.The peel of the grape-pip is made up of various layers
of cells that can be found under the skin, the most external covering. the skin of
the grapes is thicker in wine grapes and thinner in grapes for fresh consumption. It
contains coloring substances, tannins and some aromatic substances.
The juicy inside of the grape contains a great number of substances with a high
nourishing value. Approximately 80% of the dry weight is constituted by
carbohydrates, for the greater part sugars like glucose and fructose. The high
concentration allows the fermentation of the pressed grapes, from which the wine is
obtained. In the grape-pips there is also malic acid, tartaric acid, succinic acid,
minerals, vitamin c and elements like potassium, iron and sodium are also present.
The therapeutic virtues of the grape were exploited in the past for the cure of some
diseases, like the gout, lithaemia, kidney stones, with the practice of ampelotherapy
(ampelos means vine in latin).
Today a high therapeutic value is granted to the flavonoids contained in the
grapes, some pigments with a high anti-oxidant activity able to hinder the proliferation
of tumoural cells and useful in the prevention of cardiac diseases.
Wine
production
olive
Olea Oleaster
wild olive tree
Olea europea
olive
Centuries-old olives
In the south of Calabria th
Olive trees of Rosarno and
Gioia Tauro are famous with
age-old specimens (300 400
years) also of twenty meters.
Olive oil composition
Omerus called
the olive oil
“ liquid gold ”
According to oleic acid
percentage we can have
oils of different quality :
the extra vierge oil is the
best one
This presentation has been done by students
from
Liceo Classico B. Telesio
Cosenza Italy
for Comenius Project 1.2
Italia -Sverige
exchange
With the coordination of the teachers
B. Fata C. Pisani
Only for educational use