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Location & Geology |
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- The research
area of LöKAT (Landscape Ecological
Complex Analysis in Turkey) is located in SE-Turkey
(Hatay Province).
In altitude it extends from the colline to the subalpine belt at the
western slope of the Amanos Mtn. in the Dörtyol region.
As the eastern border of the Gulf of Iskenderun, the Mountain is a
late alpidic folding and a southern extension of the Iranian mountain
chain of the eastern Toros range. It continues in the Cyprian mountains.
The eastern border of the Amanos is marked by a tectonic break line
(Jordan-Maras fault basin), which has its starting point at the northeastern
border of the Amanos upfolding. As a part of the mountain range at
the Levantinian Coast, the Amanos above Dörtyol rises to its
highest peaks up to > 2.200 m a.s.l.
- In the research area
the colline belt comprises sub-marine basic and ultrabasic greenstone
series incl. serpentinite of mesozoic origin (upper cretaceous), the
middle montane belt limestones of different types incl. dolomitic
limestones (mesozoic - tertiary) and the middle to upper montane belt
(incl. sub-alpine belt) sandstone series with quarzites and siltstones
(lower to upper palaeozoic).
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Soils |
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- Very well developed
soils - in the sense of soil genetically defined chronosequences -
were found all over the above mentioned rock series.
Obviously they are far more seldom in areas of strong extensive management.
Due to divergent lithogenesis and related weathering conditions, the
depth of soil development differs greatly.
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Climate |
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- The coastal belt and
the colline landscapes underneath the resaerch area show bioclimatologically
humid to perhumid meso- to submediterranean conditions.
Real eumediterranean climatic regimes are absent in the Dörtyol
region. The entire montane belt belongs, in a pluviothermic point
of view, to the perhumid ‘non-mediterranean’ type of bioclimate. Short-term
shortages of water supply for plants on exposed sites with understocked
forest and anthropogenic soil erosion or very shallow soil cover can
be expected during summer time in spite of the favorable of humidity.
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Heavy precipitation
occurs frequently in October, February and April. Mainly in October,
strong rainfall events were measured in the research area (e.g.
62 mm h-1 or 137 mm in 5 hours). The most frequent precipitation
rates are < 5 mm d-1 and have been registered by the
climatic stations S2 (950 m a.s.l.) and S3 (1.600 m a.s.l.). The
highest rain frequency was measured in the middle montane belt (50
% days with rain per year), and the lowest in the subalpine area
(29 % days with rain per year). The altitudinal gradient of precipitation
is not linear. The highest mean precipitation rates were found in
the middle montane belt with 2.300 mm y-1. The yearly
means are similar in the lower montane and upper colline belt and
the subalpine area (for comparison Dörtyol, 28 m a.s.l., 1.022
mm y-1).
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Flora & Vegetation |
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- The southernmost distributed
extrazonal vegetation of Euro-Siberian origin on the investigated
slopes of the Amanos represents, with regard to its extension and
species diversity, the largest area with the highest abundance of
geoelements mainly of Euxinian provenance. In contradiction to hitherto
existing assumptions, the portion of endemics [cf. Draba
haradjianii and Carduus
amanus ]
is lower
than the average of the country.
- This remarkable vegetation
owes its existence exclusively to the macroclimatic conditions of
the east mediterranean area during summertime.
During this season, etesian winds with monsoonal character lead to
cloudbank
formations at the western slopes.
The supply of humidity, in combination with reduced global radiation
to nearly 40 %, and the influence of cloud cover on temperature, are
responsible for unique climatological conditions in the middle montane
belt. On the contrary, precipitations of cyclonal origin definitly
favor the easterly and not the westerly exposed slopes.
- The present climatic
situation and the reconstructed history of the macroclimate of the
E-Mediterranean area leave no doubt that the extrazonal vegetation
of the Amanos is of holocene origin. Nearly 100 % of the determined
Euro-Siberian species are identical with species of climatologically
comparable landscapes of the Black Sea Coastal Mountain (Pontus) region
and areas of the NW-Balkan Peninsula. Out of 610
determined taxa
(238KB)
(cf. separate
website with detailed information) the portion of Euro-Siberians
and biregionals are much higher than the portion of Mediterranean
geoelements. Euro-Siberian
elements of Euxinian provenance dominate the vegetation in the montane
belt
(61KB)
.
In the extremly humid zonality, a hygro-thermal S/N-gradient is recognizable.
The topographically and altitudinally related vertical arrangement
of vegetation belts shows surprising similarities to the climatological
dependent S/N-zonation of vegetation.
- The middle to upper
colline belt of the research area is covered by an anthropogenic Pinus
brutia
mixed forest. Besides several
macchie elements (evergreens are rare) in the understory the portion
of Euxinian deciduous elements is already very high (e.g. Quercus
cerris,
Carpinus
orientalis
and Fraxinus
ornus ssp.), which leads to a character of undergrowth
between ‘pseudomacchie’ and ‘shiblyak’. In valleys of the lower montane
area and mainly on the middle montane belt on limestones, Carpinus
orientalis
dominates on northwesterly and Quercus
cerris
on southwesterly exposed slopes, especially those with shallow soils.
Xero-Euxinian elements of this belt occupy mainly oligo- to mesohemerobic
sites. Shady valleys and humid ravines with atmospherically moist
and edaphically wet conditions are dominated by a Laurus
- Tilia
mixed forest, which is rich with many different ferns. Mainly on limestones
typical companions of this mesophylous forest are Staphylea
pinnata (very
frequent), Buxus
sempervirens
(frequent),
Taxus
baccata
(frequent)
and Ilex
colchica (rare,
very similar to Ilex aquifolia). Growing in soils of the sandstone
series, Fagus
orientalis
is
absolutely dominant on the entire inner montane belt up to the upper
border of forest
and timberline.
In a mosaic pattern Pinus
nigra ssp. pallasiana
stands
are admixed. Abies
cilicica occurs
very sporadically on northwesterly exposed slopes > 1.300 m a.s.l.
but covers large areas of southerly innermontane slope positions >
1.700 m a.s.l. Cedrus
libani generally
occurs very rarely.
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Flora - Vegetation & Soils |
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- The distribution of
vegetation in the research area is predominantly determined by the
possible water supply in soils during summer time. The importance
of usable field capacity (uFC) of soils decreases with decreasing
evaporation loss as a result of shade effects in valleys and gor-ges
or ravines. Sites preferred by Euro-Siberian geoelements are generally
soils with sufficient clay migration, high values of uFC mainly in
the subsoil (B-horizon) and in addition, high contents of sand and
loam fractions in the topsoil (A-horizon). The highest values of uFC
(grand total of the profile) were found in soils of the middle montane
limestone series. Mainly oligo- to mesohemerobic soils of high slopes,
ridges and crests with regressive soil development and often unproductive
evaporation as a result of high contents of humus and clay in the
topsoils, are typical sites of (East-)Mediterranean and Xero-Euxinian
geoelements.
- Highly developed soils
are generally restricted to sites hardly reachable for human beings
and their animals and rarely found in the middle montane area of extensive
cultivation (mainly grazing). Under the given climatic,
and with respect to initial lithological conditions for soil development,
the most favourable soil water contents can be found more easily on
the complex of sandstone series. The affect of floristical differentiation
of the pH-value between soils of the sandstone and limestone series,
parallel with the exposition of slopes, lead to a distinct separation
of Carpinus
orientalis
/ Quercus
cerris-
and Fagus
orientalis
- units in the area of sand-stone series.
- In general Fagus
orientalis is indifferent to the various kinds of soils
derived from different parent rocks of the Amanos Mtn. In the research
area, vegetation units dominated by the oriental beech are also well
distributed on soils originating from limestones, if these soils are
deeply and well developed (e.g. Chromic Luvisols with a distinct Bt-horizon
as a result of illimerisation). A lithologically and pedologically
based differentiation of vegetation units in areas with limestone
series or ultrabasic greenstones as parent rocks (e.g. serpentinite)
were not detected. A lack in differing species - an accepted phenomenon
- for soils derived from serpentinite, as a result of high concentrations
of heavy metals in the soil solution available to plants, was not
confirmed for the research area. On the contrary, in the heavily overgrazed
transition area of both limestone series and serpentinite the highest
species diversity and population density was found.
- The short-term as well
as the long-term nutrient supply is sufficient in soils derived from
sand-stones with moderate to very low pH-values, in soils derived
from limestone with weak alkaline soil solution and in soils derived
from serpentinite with weak acid conditions. The best nutrient supply
was found in soils derived from limestones. Due to low pH-values in
sandstone-soils, the effective Cation Exchange Capacity (CECeff)
has to be classified as ‘very low’ to ‘low’. Nutritional shortages
are maybe only a problem for low rooting species. Aluminium-toxicity
in soils derived from sandstones was not found. In soils originating
from ultrabasic greenstones, the concentration of nickel and chrome
does not reach toxic levels. The high concentration of interchangeable
magnesium in soils last mentioned were not found as limiting factors
for plant distribution.
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Numerical Ordination and Indicator-Parameter |
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- With
numerical ordinations, the following environmental parameters for
plant distribution were recognized as determining variables: on the
altitudinal gradient the continuously changing climatic conditions
and the strong decrease of ‘global radiation’ as a result of cloudbank
formations in the
middle montane belt, the very low ‘pH-values’ of sandstone-soils,
the relief positions ‘high slopes’, ‘ridges’, ‘crests’ and steep valley
sides with valley bottoms. Although the variables ‘shallow soil cover’
and low ‘usable field capacity’ correlate with exposed ‘ridges’ and
‘crests’, these variables do not explain the variance in the data
sets as well as ‘altitude’, variation of ‘global radiation’ and ‘pH-value’
(resp. ‘sandstone-formation’). Vegetation units dominated by Carpinus
orientalis show a clear correlation to mean soil layers with extremely
high usable field capacities. In contradiction Quercus cerris
- units are more related to shallow soils on ‘high slopes’, ‘ridges’
and ‘crests’. Fagus orientalis sites located in the range of
limestone series correlate strongly with very well developed soils
(e.g. Bt-horizon) with extremely high ‘uFC’ and a very
low content of ‘dead water’ - respectively ‘unavailable water for
plants’.
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Hemeroby and Indicators |
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- Man-induced modifications
of habitat factors in the research area in the past lead to changes
in abundance and dominance of highly frequent species on the altitudinal
gradient. In general, the change of plant populations probably would
be the same under ahemerobic or oligohemerobic conditions. Nevertheless,
it must be supposed that with only very low human impact over a long
period of time and under the same existing climatic conditions e.g.
Quercus cerris would already dominate northwesterly exposed
colline foothills above Dörtyol. Stands with Fagus orientalis
on limestone would expand and Carpinus orientalis would replace
Quercus cerris on most of the middle montane sites.
- Indicators for degradation
of site conditions from the colline to middle montane belt are very
well distributed as a result of openings and understocked forests,
trial structure of slopes, soil deterioration and impoverishment (with
the negative effect on soil moisture). Apart from Mediterranean species,
Pteridium
aquilinum and Ruscus
aculeatus var. angustifolius
are very frequent. Pteridium and Ruscus are rare on
very shallow soils. The intensity of landscape cultivation can be
evaluated not only by the range of (often light demanding) indicator
plant types, but also by the degree of coverage and structural diversity
of different vegetation layers. Mainly the layers < 10 cm and 10-50
cm show remarkable hints for understocked forests resp. coppice wood
or open woodland and eutrophication.
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Lifeforms on the Altitudinal Gradient |
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- The spectrum of life
forms is dominated by hemicryptophytes in all vegetation units and
altitudinal belts. With regard to the high portion of phanerophytes,
similarities with the NW-Balkan Peninsula are obvious. Thero- and
hemicryptophytes are strongly represented in the middle montane area
with high species diversity as a result of very extensive cultivation.
Phanerophytes and hemicryptophytes are the leading life forms in the
mixed beech forest of the high mountain belt. Just as the abundance
of Mediterranean and Euro-Siberian geoelements changes continuously
with increasing altitude, the spectrum of life forms changes in the
same manner. The portion of therophytes decreases and thus of hemicrypthophytes
increases. Discontinuities are related significantly to cultivation
impacts.
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Cartography & Mapping |
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- Thematical Ecological
Maps (TEMaps) have been developed on the basis of topographical maps,
soil and vegetation investigations, field notices in enlarged sections
of topographical maps, photos from the landscape, aerial photographs
and the digital classification of satellite images. Correlations of
vegetation and soil units are of special interest for comparison purposes.
However, astonishingly few coincidences have been found. The best
correlations are recognizable between soil units of shady valleys,
deeply weathered soils on limestones and - on general - soils derived
from sandstone series. The distributional pattern of vegetation depending
on exposition is not correlated with the distribution of soils. The
lowest correlations have been found in the middle montane area and
the colline belt.
- Due to the scale of
digitalized satellite images, the interpretation of small vegetation
units is strongly restricted. Shade effects, different reflections,
numerous reflectivities of parent rocks and talus deposits on the
altitudinal gradient in relation to exposition and altitude can be
the cause for many classification mistakes. Reliable results are available
only with a series of multi-seasonal and multitemporal data sets.
Presumption for the evaluation of satellite-based field data is generally
the traditionally claimed knowledge (geology, soils and vegetation)
of the landscape where vegetation mapping has to be performed.
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Society & Economy |
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- The social and economic
situation in the research area and its neighborhood is characterized
by the extraordinary density and increase of population. Besides growing
industrialisation, not only the entire coastal belt is therefore under
cultivation, but in addition and with increasing tendencies, the hilly
landscapes and mountainous regions. Due to these circumstances, rapid
changes of the coastal landscapes and namely the westerly exposed
slopes of the Amanus Mtn. are observed. The most important impacts
are: expanding of grazing areas in montane areas (increasing restrictions
in intensive cultivated coastal landscapes for traditional animal
farming are the reason), uncontrolled and illegal wood consumption
(stand inventories and descriptions of the forest management regarding
structure and composition of stands do not agree with the reality)
and expanding of (summer-)settlements with infra-structural openings
(road construction, electricity and water supply).
- Recognizable results
of increasing anthropogenous impact on the research area are: openings
and understocked forests, open woodlands (mainly loss of trees and
shrubs), desiccation of soils and increasing surface run-off with
concentrated seasonal run-off processes (with the result of negative
effects on water supply for coastal areas and the soil water balance
of mountain slopes), erosion on high slopes, crests, ridges and mainly
on steep slopes with road constructions, increasing meso- to ß-hemerobic
sites (which will be occupied by Mediterranean species with a large
amplitude of site requirements and at least deterioration of site
conditions for rare and endangered Euro-Siberian geoelements). Decrease
of species diversity and loss of genetic resources of national and
international importance.
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Copyright
© Harald Kehl
Formerly TU-Berlin · Fak. VI · Inst. f. Ökologie,
Updated on
11 December, 2023
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