STUDY AREAS
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Figure 3-11. Location of the Andalusia region (studied area) within Spain, and the highlighted province (Seville) within Andalusia, which was studied in more detail in the topographic transects analysis.
3.2 ANDALUSIA, BIOPHYSICAL BASELINE The Andalusia region is roughly situated between coordinates 36° 00’ - 38° 44’ N
and 1° 30´ - 7° 45´ W, to the south it is bordered by the Atlantic Ocean and the
Mediterranean Sea, by Portugal to the west, and by the autonomous communities
of Extremadura and Castilla-La Mancha to the north and Murcia to the east
(Figure 3-11). Andalusia consists of eight provinces. Currently, about half of the
region is natural areas and between 40 and 45% is used for agriculture. Urban
areas and open water surfaces each cover approximately 3% of the area
(Figure 3-5; Bermejo et al., 2011). Most of natural vegetation is Mediterranean
forest which is dominated by trees such as oaks, pines and firs, with dense
riparian forests, and Mediterranean shrub land. Agriculture in Andalusia has
traditionally been based on cereals, olive trees and vineyards but in modern
decades, traditional crops have been replaced with various intensive and
extensive crops (e.g., , sunflower, rice, cotton and sugar beet).
3.2.1 CLIMATE Andalusia is one of the warmest parts of Europe, with an average temperature of
16 oC and monthly temperatures varying between January (6.4 oC in Granada) and
July and August (28.5 oC in Córdoba and Seville). Figure 3-12 shows the climate
zones.
SPAIN
Mediterra
nean sea
Po
rtu
ga l
France
Marrocos
Jaen
Sevilla
Cordoba
Granada
Huelva
Cadiz
Almeria
Malaga
2°0'0"W
2°0'0"W
3°0'0"W
3°0'0"W
4°0'0"W
4°0'0"W
5°0'0"W
5°0'0"W
6°0'0"W
6°0'0"W
7°0'0"W
7°0'0"W
39°
0'0
"N
39°0
'0"N
38°0
'0"N
38
°0'0
"N
37
°0'0
"N
37
°0'0
"N
36°
0'0
"N
36°
0'0
"N0 30 60 90 12015km
1:1,400,000
±
Portugal
Extremadura
Castilla-La Mancha
Murcia
Andalusia Mediterranean sea
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62
Figure 3-12. Climate type according to De Martonne (1926), Andalusia region.
In Andalusia, as classified by De Martonne (1926; Table 3-3), it shows that the
general climate of Andalusia is a Mediterranean climate type even though it varies
depending on the specific climatic parameters of the 62 weather stations. Almería
province (in the south east of Andalusia) has arid and semi-arid climate
conditions, while Málaga and Cádiz (in the south) have semi-humid, humid and
very-humid climate types. The data used for calculation of climate areas show
limited variation of average temperature, as recorded in weather stations (varying
between 14,2 and 17 oC). In contrast, there is a significant variation in annual
mean precipitation (varying between 275 and 1074 mm).
According to climatic calculations using the climate data base of MicroLEIS DSS
(CDBm), Huércal Overa station (AL02), Almería is the most arid location in the
study area, with an annual rainfall of 275 mm, a mean temperature of 17 oC, and
potential evapotranspiration of 882.9 mm which results in an average of 10 arid
Climate type
Arid
Semi-arid
Mediterranean
Semi-humid
Humid
Very humid
Jaen
Sevilla
Cordoba
Granada
Huelva
Cadiz
Almeria
Malaga
0 30 60 90 12015km
1:1,400,000
±
Portugal
Extremadura
Castilla-La Mancha
Murcia
Andalusia Mediterranean sea
AL02
MA05
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months (in which the potential evapotranspiration exceeds the actual
precipitation) per year. The most humid area, on the other hand, is Gaucín
(MA05) in Málaga, with an annual rainfall of 1170 mm, a mean temperature of
14.9 oC, and potential evapotranspiration of 771.7 mm, which results in, on
average, 5 arid months per year (Figure 3-13).
Table 3-3. Classification of climate types according to the aridity index by De Martonne (1926): I = P / (T+10) with I: index, P: annual rainfall (mm), and T: mean temperature (
oC).
Climate type Aridity index
Arid 0 - 10
Semi-arid 10 - 20
Mediterranean 20 - 24
Semi-humid 24 - 28
Humid 28 - 35
Very humid 35 - 55
Extremely humid ˃ 55
Figure 3-13. Graphical representation of climate conditions of weather stations MA05 (Gaucín, Málaga) and AL02 (Huércal Overa, Almería). (P) precipitation; (Tm) monthly mean temperature; (ET0) potential evapotranspiration; (ARi) arid months in which the actual precipitation is lower than the potential evapotranspiration. Source: Spanish Meteorological Agency (AEMET, 2011).
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64
3.2.2 GEOLOGY According to Vera, (1994), Andalusia is divided into three main geological units
(Figure 3-14). First, the northern part consists of Sierra Morena, a crystalline
massif which is very ancient (Paleozoic), that was part of the Armorica continent.
The second part is represented by the Neogene tectonic basin of the Guadalquivir
(formed from the Langhian until present day). The third geological feature (in the
south east) is the Baetic cordillera (Triassic-Lower Miocene), which is the
westernmost part of the European Alpine chain.
Figure 3-14. Classes of lithology synthesis in Andalusia.
0 30 60 90 12015km
±
Portugal
ExtremaduraCastilla-La Mancha
Murcia
Andalusia
Mediterranean sea
Guadalquivir basin
Sierra morena
Baetic cordillera
ClassesEstuary deposits (Quaternary)
Aeolian deposits (Quaternary)
Recent fluvial deposits (Quaternary)
Old fluvial deposits (Plio-Pleistocene)
Sandstones (Pliocene)
Basic igneous rocks
Limestone (Miocene-Pliocene Sup)
Marl rocks (Paleogene-Miocene)
Undifferentiated metamorphic rocksAcid igneous rocks
Undifferentiated igneous
Sedimentary igneous rocks (Precambrian-Paleozoic)
Limestone, dolomite, greywackes, sandstones and conglomerates (Precambrian-Paleozoic)
Argillite, marls, sandstones, turbidites,dolomite and limestone (Triassic-Juras-Cretaceous-Paleogene)
Sedimentary and metamorphic rocks (Precambrian-Paleozoic)
Sandstone,Argillaceous rocks and marl (Cretaceous-Paleogene-Miocene)
Slate, sandstones and quartzites (Paleozoic-Triassic)
Variegated clays,marl,sandstone,conglomerates,gypsum and limestone (Triassic)
Schists (Precambrian-Paleozoic-Triassic)
Limestone and carbonate eminently rocks (Jurassic-Cretaceous-Paleogene)Reservoirs,ponds,marine areas and bays (Current)
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This mountainous area is the result of a series of tectonic movements of the
African and Eurasian plates and continues to be an active seismic zone (Garcia-
Castellanos et al., 2002).
The geological map of Andalusia (Project SIMANCTEL, 2006) includes 20
lithological classes (Figure 3-14), distributed within the three large units at
regional scale. The Iberian Massif (Sierra Morena) is constituted by: marginal
recent fluvial deposits (Quaternary); ancient fluvial deposits in the northern part
(Plio-Pleistocene); limestone, dolomite, greywacke, shale, sandstone and
conglomerate (Precambrian-Paleozoic); sedimentary and metamorphic rocks
(Precambrian-Paleozoic); sedimentary and igneous rocks (Precambrian-Paleozoic);
acid igneous rocks; basic igneous rocks; undifferentiated igneous rocks; slate,
sandstone and quartzite (Paleozoic-Triassic); schists (Precambrian-Paleozoic-
Triassic); undifferentiated metamorphic rocks.
The Guadalquivir basin is primarily constituted by recent sedimentary rocks:
estuarine deposits (Quaternary); aeolian deposits (Quaternary); recent fluvial
deposits (Quaternary); old fluvial deposits (Plio-Pleistocene); sandstone
(Pliocene); limestone (upper Miocene-Pliocene).
The Betic Range is constituted by: recent fluvial deposits (Quaternary); ancient
fluvial deposits (Plio-Pleistocene); sandstone (Pliocene); limestone (upper
Miocene-Pliocene); marl rocks rocks (Paleogene-Miocene); sandstone,
argillaceous rocks and marls (flysch and turbidites) (Cretaceous-Paleogene-
Miocene); limestone and carbonate eminently rocks (Jurassic-Cretaceous-
Paleogene); variegated clays, marl, sandstone, siltstone, conglomerate, gypsum
and limestone (Triassic); argillite, marl, sandstone, turbidite, dolomite and
limestone (Mesozoic-Paleogene); limestone, dolomite, greywacke, shales,
sandstone and conglomerate (Precambrian-Paleozoic); sedimentary and
metamorphic rocks (Precambrian-Paleozoic); sedimentary and igneous rocks
(Precambrian-Paleozoic); acid igneous rocks; basic igneous rocks; undifferentiated
igneous rocks; slate, sandstone and quartzite (Paleozoic-Triassic); schists
(Precambrian-Paleozoic- Triassic); undifferentiated metamorphic rocks.
3.2.3 TOPOGRAPHY In general, Spain is a very mountainous country, with an average elevation of 660
meter above sea level (masl) (the second highest in Europe after Switzerland;
Benet, 2006). As a result of the geological history of Andalusia, topography is one
of the major factors shaping the natural environment and land use.
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66
Figure 3-15. Elevation map of Andalusia. (ICA, 1999).
According to the digital elevation model, the elevation values vary from 0
(coastline and Guadalquivir River basin) to 3478 masl (Baetic Range and Sierra
Morena; Figure 3-15).
Slope gradients affects degradation processes as soil erosion rate through many
morphological characteristics. Two examples of morphological characteristics are
gradient and slope length (Torri, 1996). As shown in Figure 3-16 the slope gradient
in Andalusia ranges from <3 to >50 %. The effect of slope aspect on insolation (sun
exposure), which may vary between south-facing sunny, and north-facing shaded,
slopes. Higher energy inputs in sunny slopes affects the rate of decomposition of
organic matter, the thawing rate of snow, potential evapotranspiration and the
soil salinity (mostly in arid regions).
0 30 60 90 12015km
1:1,400,000
±
Portugal
ExtremaduraCastilla-La Mancha
Murcia
Andalusia
Mediterranean sea
Elevation (m, MSL)
0 - 200
200 - 400
400 - 600
600 - 800
800 - 1000
1000 - 12000
1200 - 1400
1400 - 1600
1600 - 1800
1800 - 2000
2000 - 2200
2200 - 2400
2400 - 2600
2600 - 2800
2800 - 3000
3000 - 3200
3200 - 3478
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Figure 3-16. Slope map of Andalusia.
Figure 3-17. Slope aspect in Andalusia.
0 30 60 90 12015km
1:1,400,000
±
Portugal
ExtremaduraCastilla-La Mancha
Murcia
Andalusia
Mediterranean sea
Slope, %
< 3
3- 10
10 - 20
20 - 30
30 - 50
> 50
0 30 60 90 12015km
1:1,400,000
±
Portugal
ExtremaduraCastilla-La Mancha
Murcia
Andalusia
Mediterranean sea
Slope direction
Flat (-1)
Northeast (22.5 - 67.5)
East (67.5-112.5)
Southeast (112.5-157.5)
South (157.5-202.5)
Southwest (202.5-247.5)
West (247.5-292.5)
Northwest (292.5-337.5)
North (337.5-360, 0-22.5)
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68
Aspect also indirectly affects erosion processes due to decreased vegetation cover
in dry, sun-exposed, slopes (Zachar, 1982). Slope aspect in Andalusia is shown in
Figure 3-17.
3.2.4 GEOMORPHOLOGY Ten main morphogenesis types are found in Andalusia: fluvio-colluvial, tidal-
fluvial, aeolian, denudation, karst, structural, periglacial, volcanic, coastal and
submarine.
The Iberian massif is generated by the collision between Laurasia and Gondwana
plates since the Late Paleozoic. In the Mesozoic Era, this area was dominated by
intense erosion, which led to the development of extensive planation surfaces.
Indeed one of the most characteristic features is the presence of extensive
piedmont of alluvial deposits composed of siliceous clasts with a reddish
argillaceous matrix.
The most striking geomorphologic features in the Iberian Massif are related to the
underlying lithology and structure. Particularly, in Sierra Morena mountains, the
differential erosion of folded Paleozoic rocks with a contrasting resistance to
erosion (e.g. quartzite and slates), has produced a distinctive ‘Appalachian-type’
topography (Gutiérrez et al., 2013).
The Baetic Range represents a mountain belt with high peaks. This chain is
affected by considerable convergence (4mm/yr) and tectonic activity. The Baetic
may be divided in two principal zones, the inner and the outer zones. The inner
zone is dominated by a structurally complex and metamorphosed basement and
rocks forming an anticlinal stack. The outer zone is formed by allochthonous
south-verging structural units made up of Mesozoic and Cenozoic sedimentary
sequences detached from the Paleozoic basement. The Betics chain also includes
numerous postorogenic Neogene and Quaternary basins. Most of these basins are
related to the north-south compression vectors, currently affected by tectonic
inversion. In this area, the main geomorphic factor is tectonic activity, which
affected the landscape. The Eastern Betic Range shows examples of fault-
controlled mountain front and alluvial fan system. The development may be
affected by tectonic activity, climate variability and base level changes. In this
area, the evolution of the drainage network, largely guided by postorogenic
basins. The study of this basins is important for understand long-term changes in
fluvial systems. Limestone karst is well-developed, mostly in the Outer zone,
controlled by active faults, karren fields and cave system (Gutiérrez et al., 2013).
STUDY AREAS
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The Sorbas basin presents landforms related to Messinian gypsum dissolution, but
are also developed on Triassic evaporite.
Evidence of Quaternary glaciations is restricted to the Sierra Nevada. These
mountains represent the southernmost glaciated area in Europe, which probably
occurred before the global Last Glacial Maximun. The spatial distribution of large
landslides in the Betics is mainly controlled by litho-structural factors, active
tectonics and fluvial incision (Gutiérrez et al., 2013).
The morphological depressions control the path of the main fluvial system. The
most important depression in South Spain is the Guadalquivir basin. This basin
represents a foreland basin of Baetics chain. The East/Northeast, West/Northwest
Guadalquivir basin has been open to the sea during its entire evolution. The
southern half of the basin is dominated by olistostromes, whereas the northern
half is mainly underlain by autochthonous soft marl sediments. The upper and the
middle reach of the valley, currently show the rectilinear northern margin of the
basin, displays an extensive terrace sequence on the southern margin. In the
lower reach, the river splits into several anostomosed channels flowing through
marshland separated from the sea by a long spit bar with a large superimposed
dune field (Gutiérrez et al., 2013). The Iberian Peninsula shows a very extent and
diversity of the coastal environments. The main factors that control the
geomorphology and Quaternary geology of the Spanish coasts include: Eustatic
changes, Litho-structural factors (neotectonic deformation); Geographic location
between Europe and Africa continents (Straits of Gibraltar); Tidal range; the
prevailing winds respect the coastline and Human activity. Generally, the coasts
have been affected by uplift, which has produced marine terraces.
The Geomorphic features of the Atlantic coast in the Gulf of Cadiz are largely
controlled by the different geological units and the presence of active faults. In
the Guadalquivir basin, the low relief coast has extensive estuaries and marshes
associated with the lower reach of the main river, partially closed by a large dune
fields. The Atlantic coast developed in the Strait of Gibraltar has a strong
structural control and shows a good sequence of raised marine terraces and cliff,
interrupted by small bay and caves. The geomorphology of the coasts in the
Mediterranean is largely dominated by distribution of area affected by positive
and negative tectonics and micro tidal regime.
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70
Figure 3-18. Principal rivers and basins in Andalusia.
3.2.1 HYDROLOGY Figure 3-18 shows that in Andalusia there are four main basins, Guadiana in the
northwest, Guadalquivir in central Andalusia, Segura in the southeast, and Sur in
the south. The most important river is the Guadalquivir and its main tributaries:
Guadalimar, Guadiana Menor, and Genil.
3.2.2 SOILS De la Rosa et al (2009) stated that using soil type information in decision-making is
at the heart for sustainable use and management of agricultural land.
Typical soils of Andalusia compose an exceptionally diverse sample of the diversity
of Mediterranean soils (De la Rosa, 1984). According to FAO classification (FAO-
UNESCO-ISRIC, 1988), the main soil orders are Cambisols (33%), Regosols (20%),
Luvisols (13%) and Leptosols (11%) (CSIC-IARA, 1989). Figure 3-19 shows the most
typical soils of Andalusia and Mediterranean region and Figure 3-20 shows the
dominant soil sub-group and land use in the 62 natural regions of Andalusia.
Sur
Guadalquivir
Guadiana
Guadiana
Segura
Segura
Segura
Rio Genil
Rio Guadalquivir
Rio
Odie
l
Rio Guad
elete
Rio T
into
Ra de Huelva
Rio V
iar
Rio Almanzora
Rio
Gua
dalé
n
Rio Guadiato
Rio Nacimiento
Rio
de
Gua
dal
quiv
ir
Rio Barb
ate
Rio Bem
bezar
Rio Chanza
Rio Guadalimar
Rio Guadiana Menor
Rio
Gua
rizza
s0 30 60 90 12015
km
1:1,400,000
±
Portugal
ExtremaduraCastilla-La Mancha
Murcia
Andalusia
Mediterranean sea
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Figure 3-19. Typical soils of Andalusia, and the Mediterranean region in general (De la Rosa el al., 1984). Codes indicate location province (Al, Almería; CA, Cadiz; CO, Cordoba; GR, Granada; HU, Huelva; JA, Jaen; MA, Málaga; SE, Seville) and number in the SDBm database, followed by comarca (landscape unit).
CHAPTER 3
72
Figure 3-20. The dominant soil sub-group and land use in the 62 natural regions of Andalusia. Modified from De la Rosa et al. (1984).
3.3 EL-FAYOUM PROVINCE, BIOPHYSICAL BASELINE El-Fayoum province is located in the northern part of Egypt, approximately 90 km
south of Cairo, and includes six districts with a total area of 6086 km2,
approximately between coordinates 29° 02´-29° 35´ N and 30° 23´-31° 05´ E
(Figure 3-21). It offers a great potential for agriculture, thanks to the water supply
from the River Nile. The area selected for this study is the El-Fayoum depression,
which excludes the desert part of the province.
Land use
Agriculture zones Forest zones Pasture zones
THXV
LHXI
THXU
THXI
THXI
CHXI
LHXI
LHEM
THXATHXA
TRXA
TXTE
TXTE
THXV
CHXV
TXTE
TXTE
FDUI
TPXA
THXM
THXI
THXV
THXV
VPXA
AXFE
THXV
CHXI
THXI
TDUI
THXI
CHXI
EHXV
UHUM
TXFE
LXTE
VHAR
THXV XHCR
LRXA
TFAE
LHXI TFAE
TXTE
TXFE
LHEM
TXTE
AHXATXFE
TRXA
TRXA
TXTE
LHXI
THXAAPXA
HUAE
EHXVTRXA
EHXM
CRXA
CRXA
CRXA
TFAE
TXFE
CHXA
0 30 60 90 12015km
±
Portugal
Extremadura
Castilla-La Mancha
Murcia
Andalusia
Mediterranean sea
Soil sub-group (USDA, 2010)Aquic Haploxeralfs (AHXA)
Aquic Palexeralfs (APXA)
Calcic Haploxeralfs (CHXA)
Calcic Rhodoxeralfs (CRXA)
Lithic Rhodoxeralfs (LRXA)
Typic Haploxeralfs (THXA)
Typic Palexeralfs (TPXA)
Typic Rhodoxeralfs (TRXA)
Vertic Palexeralfs (VPXA)
Vertic Haplargids (VHAR)
Xeric Haplocambids (XHCR)
Aquic Xerofluvents (AXFE)
Haplic Udarents (HUAE)
Lithic Xerorthents (LXTE)
Typic Fluvaquents (TFAE)
Typic Xerofluvents (TXFE)
Typic Xerorthents (TXTE)
Calcic Haploxerepts (CHXI)
Typic Dystrudepts (TDUI)
Typic Haploxerepts (THXI)
Fluventic Dystrudepts (FDUI)
Lithic Haploxerepts (LHXI)
Entic Haploxerolls (EHXM)
Lithic Haprendolls (LHEM)
Typic Haploxerolls (THXM)
Udic Haplustolls (UHUM)
Typic Haploxerults (THXU)
Chromic Haploxererts (CHXV)
Entic Haploxererts (EHXV)
Typic Haploxererts (THXV)