Geographically, Turkey forms a natural bridge between
the old world continents of Asia, Africa and Europe. The Anatolian peninsula is the westernmost point of Asia,
divided from Europe by the Bosphorus and Dardanelles straits. Thrace
is the western part of Turkey on the European
continent.
Examination of Turkey's
topographic structure on a physical map of the world shows
clearly the country's high elevation in comparison to its neighbors, half of the
land area being higher than 1000 meters and two thirds higher than 800 meters.
Mountain ranges extend in an east-west direction
parallel to the north and south coasts, and these are a principal factor in
determining ecological conditions. This also means that apart from the Asi river in Anatolia and the Meriç
in Thracian Turkey, all Turkey's rivers have their sources within its borders and flow into
the sea, into neighboring countries or into interior
drainages. Turkey has seven river basins. The principal rivers in the Black Sea basin
being the Sakarya, Kizilirmak Yesilirmak and Çoruh.
There are also several rivers with short courses but
high water flows in the Eastern Black Sea region,
such as the Ikizdere, Hursit Cayi and Firtina. The highest waterfall in Turkey is on the Totum river
here.
The Marmara basin has fewer rivers, the longest being the Kocaçay (whose upper and
middle reaches are called the Simav and Susurluk respective) which rises on
Mount Murat and flows into the Marmara Sea from
the south.
The Kücük Menderes, Büyük Menderes and Gediz rivers
in the Aegean basin lend their names to the plains
which they water.
In the Mediterranean basin the principal rivers are the Aksu, Köprüçay, Manavgat, Göksu, Ceyhan and
Seyhan. The Manavgat waterfall on the Manavgat, Düden waterfall on the Düden and
Yerköprü waterfall on the Ermenek are among the scenic attractions of the region. The Aladag waterfall springing directly
from the mountainside are one of the sources of the sources of the Seyhan river.
Two major rivers flow from Turkey into the Caspian Sea basin, the Aras and Kura.
Water from Turkey flows into the Indian Ocean through
the Gulf of Basra via the famous Euphrates and Tigris rivers.
Turkey also has two inland drainage basins. The first
is the Central Anatolia basin which contains
the Tuz Gölü (salt lake) in Konya, and the Yay, Seyfe, Kulu and several other satellite
lakes. The major river in this
basin is the Çarsamba which is out flow of Beysehir Lake and contributes a large
volume of water for irrigation of the fertile Konya
Plain, and is linked by a canal to Tuz Gölü.
The Karasu, Incesu, Deliçay and Bendimahi rivers
flow into the interior drainage basin of Van. There are
waterfalls on the Bendimahi.
Another significant aspect of
Turkey's topography is its continental character, preserved in the ancient name
of Asia Minor. This land mass is indeed a small scale
continent in many respects, above all with respect to the climate of the interior. In some provinces the temperature
difference over 24 hours can be as much as 20 degrees Centigrade. During the
spring months it is not unusual to find weather typical of two or even three
seasons at different locations around Turkey in a
single day. The Mediterranean coast may be
enjoying summer heat while the temperate Black Sea
region gets as much as 2000 mm of precipitation in some places, there are
parts of Central Anatolia with an average
precipitation only one eighth of this total.
These wide variations in temperature and precipitation affect the country's
flora and fauna, both in quantity and in range of
species. some parts of Turkey consist of arid highlands
whereas others are thickly forested, and differences such as these play a
crucial role in the distribution of wildlife around the country.
The fact that Anatolia is surrounded on there
sides by sea, its situation in the temperate climatic zone, its geological and geomorphic structure, and
topography are all contributing factors. The four seas
around Turkey each reflect a different ecological
character. Salinity is 18 per thousand in the Black
Sea, 23 per thousand in the Marmara Sea, 32
per thousand in the Aegean Sea and 38 per thousand
in the Mediterranean Sea. There is no other country in
the world with such a wide variation of salinity levels along its shores, and
the variations in ecological structure of these seas affects the life forms
which inhabit them, from phyto planktons and seaweeds to fish and marine mammals
such as dolphins.
Geological and topographic structure are among the main factors affecting
diversity of species in terrestrial ecosystems. While the mountain ranges running parallel to the Black Sea and Mediterranean
create a barrier for rain clouds moving inland, they cause abundant rainfall on
the mountain slopes facing the coast. On the Aegean
the mountain ranges run perpendicularly towards the coast, divided by broad
valleys which allow the maritime climate to prevail
several hundred kilometers inland. Alluvion carried by the rivers has created fertile plains in this Aegean region. Eastwards these mountain ranges move closer
together in Central Entail, spreading apart once more in northeast and southeast
Turkey. The height of plains and plateaus in Central Anatolia varies from 700 to 1100 meters,
while in Eastern Anatolia this rises to
1100-19 hundred meters, and drops to 700-500 in Southeast Anatolia. Despite the existence of
broad plains and plateaus, the topography is largely hilly and mountainous
across Turkey as a whole.
Turkey has one peak of over 5000 meters in altitude
(Mt. Ararat), three over 4000 meters and 129 peaks
exceeding 3000 meters. Such an irregular topographic structure has created a
wide diversity of ecological conditions and species. Now let us take a look at
the geological history of the country, which has also played a part in creating
the natural diversity which exists today.
Towards the end of the Quaternary Era the earth underwent four ice ages.
During the cold periods when the glaciers expanded, animals seeking warmer
climes moved southward into the Iberian peninsula, the Anatolian peninsula and Southeast Asia. This migration
enabled these species to survive periods of glaciations. While some later
returned to their former habitats, others remained in their new homelands, which
explains why Turkey's wildlife today includes species of
northern origin.
The distribution of flora and fauna species along
a north-south axis during these glacial periods shifted to an east-west axis
during temperate intervals. This further increasing the biological
diversity.
The main migratory routes for birds between Asia, Europe and Africa pass over
Turkey, and this has also been a factor in expanding the
number of species found here for part of the year.
The combination of all these factors has resulted in a diversity of native
plant animal species which is one of the highest in the world. While in terms of
bio-geographic region Turkey lies in the Palaeartic zone,
native species include those typical of the Oriental and Ethiopian regions. When
we remember that bio-geographic regions cover vast areas, the significance of a
species range drawing on there different regions can
be better appreciated.
A comparable diversity can be seen in the human history of Turkey, where since prehistoric times many different
peoples have settled, some to build civilizations and
others to pass on to other continents. As a consequence this soil has been
fought over time and time again so strategic in geopolitical terms. Over the
past ten thousand years more than twenty peoples have left their mark on Turkey. Civilizations have risen
and fallen in successive waves some falling victim to invasion by newcomers,
some to disease epidemics, and others to natural disasters such as earthquakes.
Fresh water sources have always been a key determinant in human settlement,
and where these sources have been related to tectonic
faults. they have attracted settlers into areas close to earthquakes centers.
Natural resources which have benefited mankind in various ways for thousands
of years have gradually been used up. Forests and
their wildlife have suffered most from this process. Not only have trees been
felled for timber and firewood, but set alight deliberately by ancient peoples
as a means of capturing enemy towns. Even using primitive axes, people were able
to destroy vast tracts of forest. Deforestation has led to serious erosion,
which began around 2700 years ago. Yet despite thousands of years of destruction
by logging, herds of goats, and fire, Turkey still has
large tracts of beautiful natural forest land.