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Land
Degradation Problems
In the
Euphrates Basin, Turkey
By: M.
Ozturk1, H. Ozcelik2,
S. Sakcali3,
A.Guvensen1
The
Euphrates-Tigris basin is a historically important watershed area in the world
and plays an extremely important role in the water availability of Middle East.
The river is the longest of all the rivers in SW Asia, formed by the confluence
of the Karasu and the Murat
rivers, which start in the highlands of eastern
Turkey. It is 2740 km. long with nearly 2000 km. lying in Turkey. The actual
annual volume of water is 35.9 billion cubic meters, 98% of which is
contributed by Turkey. The river flows generally South through Turkey into
Syria, then southeast through Iraq joining Tigris to form the
Shatt al Arab. In its upper course, the Euphrates
flows rapidly through deep canyons and narrow gorges. The middle Euphrates
traverses a wide floodplain in Syria, where it is used extensively for
irrigation. In Syria and Iraq, it loses velocity and becomes a slow running
stream. The modern waterworks along the Euphrates do not equal in scope those
of ancient times when Babylon and other civilisations flourished on the banks
of Euphrates. Mesopotamia, birthplace of many great civilisations, gave life to
millions of inhabitants who depended on the waters of the
Euphrates
and the Tigris for survival. Irrigation and agriculture played an important
role in the area. However, as the maintenance of irrigation and drainage
networks was neglected, the siltation of canals and
the salinization of fields eventually made the land
unsuitable for agriculture. The same situation is expected to arise in the
Euphrates and Tigris basins in Turkey in near future if steps are not taken.
Since nearly 2000 km. of the Euphrates lie within the borders of
Turkey,
this paper enlightens the land degradation situation in the Turkish side in
particular upper parts of the
Euphrates
basin and its environs, which covers most of the East Anatolian geographical
region. Harsh climatic conditions in the region result in higher mechanical
weathering of parent material than chemical one, as
such soils are pebbly in nature. Main soil types met within the area are;
alluvial, colluvial, chestnut, brown,
regosols, basaltic, organic, and arid soils. The
area investigated during the present survey exists at a place where different
types of climates inter-cross and mix up, but in general climate is
characterised by long and harsh cold winters. From north to south and east to
west temperatures increase gradually. Summer rains are excessive than winter
ones particularly in the northeast around the states of
Erzurum
and
Kars.
Hottest month here is August with a mean maximum temperature of 24-28
oC and in the coolest month mean minimum
varies between -16 to -17 oC. Highest
rainfall is observed in Tunceli (1003.8 mm) and
lowest in Erzincan (359.6 mm). Extremely cold
temperatures of - 45.6 oC have been
recorded around Agri, whereas around
Malatya
and Elazig summer temperatures reach 42
oC.
Demographic Developments:
Human activities are the determining factor at all stages of degradation. The
causes, mechanisms of deterioration, and the impacts, underlying this
phenomenon originate from demographic developments.The
population problem in
Turkey
started after first world war and national war of
liberation. The demographic developments followed an increasing trend all
through
Turkey
between 1927 (13.65 million) and 2000 (70 million). The population density in
the
Upper Euphrates
and environs also went above the average,with
highest growth observed in
Erzurum.
Land Use:
The region is rough topographically, plateaus being very high in particular
around
Erzurum,
Agri, Van and Hakkari,
where high altitude mountains are gathered together. Grasslands cover large
areas around these states due to the topography. They have an area of 8.900.000
ha, which is 41% of the total grasslands of Turkey. Agricultural land is found
mostly around the state of
Malatya,
Agri and
Erzurum.
Cattle raising in particular sheep is thus very
important in this region. Most of the grasslands are moved for winter fodder.
Others are used for grazing in summer. Agricultural products sown are mainly
cereals, namely; wheat, barley, rye, lentils and chickpea. Eastern parts mainly
sow fodder crops and legumes. Industrial plant cultivation is also common in
the area together with tuberous plants. Out of fruit trees we commonly get
apples, pear, plum, walnut and prune.
Plum
is one of the major exported products from
Turkey and
its centre lies in
Malatya.
Tobacco cultivation is dominant in
Malatya,
Elazig, Bitlis, parts
of Van and sunflower in Mus.
Land
Degradation:
Industrialisation and demographic explosion have been important driving forces
in the heavy urbanisation. Study area experienced greatest constructional
activities during the last decade loosing 16.000 ha. of
prime quality land.
The soil surface
including the top layer of the soil at the interface between earth and
atmosphere is the place where atmospheric attack is maximum.
The processes of soil degradation are accelerated when the vegetation is
destroyed by human activities. The first recorded civilisation of the Sumerians
was thriving in the southern Tigris-Euphrates Valley by the 4th
millennium B.C. Over the course of years, Sumerian irrigation practices
destroyed the pedosphere in such a way that this
civilisation collapsed. However even today vast areas of Iraq look like snow
covered fields. Latest trend in our study area has been use of best quality
arable lands for urbanisation districts, highway construction,
touristic establishments, sports complexes,
universities, air-ports and other activities. Uptill
now 60 percent of land has been used for this purpose and it belongs to the
most productive class in the soil grouping system of
Turkey.
In all 129.709 ha have been used for urbanisation and have got lost in this way
and millions of hectares of land are awaiting planning due to wrong use or over
use. An increase in the land for construction on monetary basis results in
decrease in the productive value of cultivated area. The brick and tile
factories also are using large areas of the productive land. In the upper parts
of the Euphrates nearly 188.000 ha have enough drainage, 91.000 ha suffer from
bad and 3.400 ha high drainage. In all 2.1 million ha.
area is facing very strong, 5.2 million ha.
strong and 3.7 million ha.
medium erosion. More than 108 million tons of soil is transported by the
Euphrates annually. Biological degradation is the reduction in the quantity of
organic matter and living organisms in particular plant cover decomposition,
whereas chemical degradation includes salinity, alkalinity, or acidity. A high
concentration of salts in the soil gives rise to saline or alkaline soils. This
is often the result of irrigation without adequate drainage. Soil and salinity
problems are more widespread and acute in arid than in temperate areas. About
900 million ha.of land are presently affected by
excessive salts in the world, one of these being
Nile
valley where 1.2 million ha. of land has got exposed
to salinization and water logging. Salt-affected
soils are especially common in irrigated regions of
Asia,
Australia, and Western USA. The accumulation of the soluble salts of Na ions (salinization)
produces soil degradation over the entire profile, resulting in such harmful
effects as: changes in compactness, porosity and permeability, organic matter
content, soil pH, plant cover characteristics, soil-plant-water balance. The
man-made share of these salinity problems arises principally from rasing of the
water table through continuous passage of large amounts of H2O
through unsuitable canals, thus converting large productive areas from a
renewable resource to a non-renewable one. According to recent estimates, over
220 mill. ha.
of land are irrigated worldwide. Approximately 25 to
40% of that land is affected by salinization.
In the fertile crescent Tigris-Euphrates rivers salted up
5-2 millennia ago and resulting in the collapse of the civilisation.
Even today flooding and over irrigation have started creating serious problems
of soil salinization in
Syria
and Iraq. A similar situation is observed in this area in Turkey as well. The
Euphrates, Tigris and Van basins are presenting an alarming situation with over
75.000 ha facing salinity-alkalinity problems.
Plant
Diversity:
Forest
vegetation in the Euphrates Basin and its environs has been very dense but with
time has become very poor due to years of degradation activities. Human impact
has resulted in a decline in the habitat as well as plant diversity. Nearly 50
percent of the forests have been heavily destroyed. On an average every year
timber in Turkey is harvested at a rate of around 7 million m3 and
upper Euphrates basin and its environs have a major contribution in it. The
firewood production lies around 35 million m3 in Turkey, most of
which is used in the area under question. Forests are present at the edge of
plains in tectonic depression. Dry forests are found at high
elevation,being sparse
and poor due to aridity as well as heavy biotic pressures. Tree line occurs at
2700 m. Quercus
forests extend from the natural steppe to the subalpine belt. The South-eastern
Taurus mountains are characterised by oak forests, mainly Q.
infectoria ssp.
boissieri, Q.
ithaburensis
ssp.
macrolepis, Q.
brantii, Q. libani, Q.
robur ssp.
pedunculiflora, and Q. petraea.
P. sylvestris forests are found in pure
stands in the vicinity of Sarikamis in the NE of
Anatolia. Over exploitation has resulted in a decrease in the genetic diversity
existing previously in these forest ecosystems. The situation of plant
diversity in general is threatening. Nearly 50 species have been recorded to be
under a threat of extinction. These include: Aconitum
cochleare Woroschin, Allium
microspathum Ekberg, Astragalus
altanii Hub.-Mor.,
Brassica tournefortii
Gouan, Coccinia
macranthera
(Banks&Sol.)
Brand var. macranthera, Corydalis
rutifolia (
Sibth. & Sm.) DC. ssp.
kurdica Cullen & Davis,
Crepis hakkarica
Lamond, Cymbocarpum
erythraeum (DC) Boiss.,
Delphinium carduchorum, Dianthus
muschianus Kotschy
& Boiss., Gypsophila
bitlisensis Bark., G. paniculate L. var.
araratica Hub.-Mor., G.
tuberculosa Hub.-Mor.,
Hypericum formosissimum
Takht., Inula
heleniumL.,
Iris paradoxa Steven, Plantago
anatolica Tutel &
Mill., P. euphratica
Decne. ex Barnéoud, Potentilla
discipulorum Davis, Ranunculus
crateris Davis, Rheum
ribes L., Rumex
amanus Rech.,
Sedum inconspicuum Hand.-Mazz.,
Verbascum nudicaule
(wydler) Takht.,
Zizyphus jujuba
Miller. In particular endemics are facing a greater threat. This area shows
an endemic ratio of 20-25%.
Status of
some species on the basis of IUCN categories.
(Ex: Extinct. R: Rare. V: Vulnerable. K:
Insufficiently known).
Astragalus altanii Hub.-Mor.-K
(Endemic), A. macrouroides Hub.-Mor.
- K (Endemic), Brassica tournefortii
Gouan–K,
Convallaria
majalis
L. var.
transcaucasica (Utkin
ex Grossh) Knorr.-K,
Corydalis rutifolia
Sibth. & Sm. DC.
ssp. kurdica
Cullen & Davis-K (Endemic),
Crepis
hakkarica
Lamond-R
(Endemic), Delphinium carduchorum
Chowdhuri & Davis-K (Endemic), Gypsophila
bicolour (Freyn & Sint.)
Grossh.–R, G. bitlisensis
Bark.-R (Endemic), G. paniculata L. var.
araratica Hub.-Mor.-R
(Endemic), G. tuberculosa Hub.-Mor.-R
(Endemic), Inula
helenium L ssp. orgyalis
(Boiss) Grierson -
R (Endemic), Iris paradoxa Steven- R, Plantago
anatolica Tutel &
Mill.-R (Endemic), P. euphratica
Decne. Ex
Barnéoud-R (Endemic), Ranunculus crateris
Davis - R
(Endemic).
Turkey is
regarded as one of the eight major gene centres on earth, due to the presence
of wild relatives of many domesticated plants in the country. For example, wild
progenitors of such cultivated plants as lentil, chickpea, wheat, peach,
almond, and pistachio are native to Turkey. The Euphrates basin in particular
is home for many of these species. As such soil degradation will lead to not
only the loss of plant but also genetic diversity.
Conclusions:
The spread of technology and culture together with a rapid growth of human
population has spread the desertification process to every continent.
Degradation is a problem with ancient roots. Cutting of forests, overgrazing,
and salt accumulation in irrigated lands led to desertification in Mesopotamia,
and the lands bordering the
Mediterranean
more than 2000 years ago. Archaeologists have clearly shown that more than
climate change we the humans have changed once rich and populous areas to
desolation and poverty. Many ancient civilisations once enjoying a golden age
crumbled in ruins and lie buried in debris, because of destructive treatment of
the lands on which they were dependent for their living. The occupation of man
has been so devastating that with a few exceptions, a desert condition is often
associated with his long habitation of a region. In the first place, semi-arid
to semi-humid regions proved the most favourable sites for the early
development of human culture followed by their degradation through processes of
soil erosion, accelerated by the exposure of soil surfaces protected by a dense
plant cover. If we are to escape similar fate of induced impoverishment and the
desiccation of land, it would be more plausible to start taking measures now
through well organised ecological land use planning. The degradation cannot be
arrested by physical or technical means alone. There is a large body of
evidence available regarding the fact that these types of short time treatments
have accentuated the problem quite seriously. In the valleys of
Khorezm and Zeravshan
there was formerly a flourishing strip of oasis which is now a desert, the
reason being social and political dynamics of degradation. Following measures
will prove more helpful in the long run: creating environmental awareness
through environmental education at all levels, women should be given a pivotal
role in decreasing population growth rate, socio-economic status of rural areas
should be upgraded, land tenure systems and size of land holdings need be well
planned, species with high potential for food, fibre and energy should be grown
using ecological farming systems and marginal land for cultivation and grazing,
cultural and religious hinderances should be
evaluated together with prevailing political trends as these can interfere with
the implementation of a programme.
1
M. Ozturk and A.Guvensen,
Ege
University, Centre for Environmental Studies,
Bornova-Izmir,
Turkey
2
H. Ozcelik,
Suleyman
Demirel
University, Biology Department,
Isparta,
Turkey
3
S. Sakcali
Marmara
University, Biology Department,Goztepe-Istanbul,
Turkey
This article has been
reproduced from the archives of EnviroNews - Newsletter of ISEB India.
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