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Results
A syntaxonomical and synecological research on the steppe vegetation of the Karacadağ Mountain (Şanlıurfa-Diyarbakır / Turkey)
Brief description of the area
Geography
Karacadağ is an extinct volcanic body lying
between northwest of Şanlıurfa and southwest
of Diyarbakır with the direction of northsouth.
Geographic position of Karacadağ is in
between 37 o 30’ 25’’-37 o 59’ 05’’ north latitudes
and 39 o 20’ 27’’-40 o 0’ 0’’ east longitudes. e
top point of Karacadağ Mountain is Mirgimir
Hill (1981 m). e other important altitudes
of Karacadağ are Mandal Hill (1895 m),
Besrek Hill (1350 m), Keluşak Hill, Hazel Hill
(1839 m), Bakşo Hill (1883 m) and Kollubaba
Hill (1957 m). Most of these hills are chapped
by small streams which dry in summers.
Geology
Volcanic Karacadağ body separates Southeastern
Anatolia into two drainage basins; one
of them is Tigris river in the east and the other
is Euphrates river in the west. is body can
be described as a big lava shield composed of
basaltic lavas. Karacadağ volcanic body is
formed through overlapping of basaltic lava
domes. ere is no volcanic structure on
Karacadağ that is eroded excessively. e
slope of volcanic (~2 o ) body from top to the
periphery parts is very low (Sözer 1984). As
Karacadağ is not very high it also does not
seem grandiosely. e lava plateau which also
includes Karacadağ has such low slope that it
seems flat. A little increase in this slope is seen
in the piedmonts of Karacadağ. e Karacadağ
body is chapped by the valleys which lie
from the center to the periphery in a beam
like manner (Tolun 1954). e Karacadağ
block has taken today’s shape as a result of the
tectonic events occurred at the end of
Pleocene era and at the beginning of Pleistocene
era (Sayar 1932).
Soils
A large part of Karacadağ is covered by
basaltic soils. However, lithosol soils which are
among the azonal soil groups and of which
bedrock is basaltic are seen in the low slope
locations. ese lithosol soils cover smaller
area than the coverage of brown forest soils,
bare rock which is an unused area, detrituses
and colluvial soils (Anonymous 1994; 1995)
(Figure 2).
ecologia mediterranea – Vol. 36 (1) – 2010
According to the results of analysis, soils are
clayish-loamy and loamy textured. ese soils
are among the soils which have the most
appropriate physical property for the plants.
Saturation ratios differ by depending on soil
texture and these ratios are highly suitable for
the growth of plant roots. pH of the soil has a
slightly acidic character (average pH is 6.2).
ese pH values are ideal for the plant growth
and they are suitable for taking up many
micro elements and phosphorus. Lime ratio
changes from 1.4% to 1.5% and it is low. Phosphorus
and potassium which are important
for the plant growth are in a sufficient level in
the soils of the region. With respect to results
Figure 2 – The great soil groups of Karacadağ.
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