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Research Journal of Environmental and Earth Sciences 4(3): 308-315, 2012
ISSN: 2041-0492
© Maxwell Scientific Organization,2012
Submitted: December 02, 2011
Accepted: January 04, 2012
Published: March 01, 2012
Diversity of Halophyte Desert Vegetation of the Different Saline Habitats in
the Valley of Oued Righ, Low Sahara Basin, Algeria
Halis Youcef, Benhaddya Mohammed Lamine, Bensaha Hocine, Mayouf Rabah,
Lahcini Ali and Belhamra Mohamed
Scientific and Technical Research Center for Arid Areas (CRSTRA), BP 1682 RP,
Biskra 07000, Algeria
Abstract: The aim of the present study was to investigate the floristic composition and diversity of the different
habitat types in the saline areas of the valley of Oued Righ, locating in the low Sahara basin of Algeria. Three
distinct saline habitats were examined: saline soil habitats, subsaline soil habitats, and waterlogged habitats.
A total of 67 stands along the study area were investigated using the quadrat method, and different vegetation
parameters, such as cover, frequency, density, and Importance Value Index (IVI), were recorded. Differences
of species diversity and richness between saline habitats were also compared. A total of 38 plant species
belonging to 29 genera and 13 families were identified from the three studied habitats. Chenopodiaceae was
the predominant family. The majority of the species were of Saharo-Arabian distribution. Chemaephytes had
the highest contribution to the life forms spectra. Species composition in the different habitat types showed
differences in species richness. Subsaline soil habitats were the most diverse, followed by saline soil habitats.
Waterlogged habitats had the lowest diversity. The floristic composition and the dominant species of each
habitat were presented. The potential role of the halophyte species was discussed. These findings may lead to
a better understanding of the functions, requirements, and sensitivities of these ecosystems.
Key words: Algeria, floristic diversity, halophyte vegetation, oued righ, Sahara desert, saline habitats
and moderately saline lakes, salty and brackish swamps,
streams and areas with high ground-water etc. High
salinity, in combination with high temperatures, exert a
strong influence over the distribution of plants in the arid
and semiarid areas (Khan et al., 2001; Grattan and Grieve,
1999).
Large inland salt flats (inland Sabkhat and Chotts) are
found in various parts of Oued Righ. Chott Merouane is
the largest of these and, after chott Melrhir in the region
of Souf, the largest on the Sahara of Algeria. Chott
Merouane is one of the internationally important wetlands
catalogued in Algeria. It was designated as a wetland
nature reserve under the international RAMSAR
convention in 2001. In addition, Oued Righ is the richest
part of Sahara desert of Algeria in aquatic ecosystems.
The presence of various wetlands in the region, e.g.,
canals, irrigation and drainage networks, salt lakes and
salt marshes create high suitable habitats for wildlife
species, compared to the surrounding areas. The main salt
lakes in Oued Righ are: Temacine Lake, Merjaja Lake,
Megarine Lake, Ain Ezerga Lake, and Ayata lake. These
lakes are of international conservation importance for
migratory birds. Among these lakes, which have a rather
rich flora and fauna, Ayata and Temacine Lakes are
declared as special environment protection areas and they
were declared as RAMSAR sites.
INTRODUCTION
The region of Oued Righ, also known as the valley of
Oued Righ, is located in the northeastern Sahara desert of
Algeria (low Sahara basin), occupying an area of about
600,000 km2. Climatically, this zone falls under hyperarid
conditions and belongs to the Saharo-Arabian
phytogeographical region. Along this valley, there are a
number of large oases sited in depressions where ground
water approaches the surface. The presence of these oases
with various water ways (irrigation and drainage
networks) increases the humidity and allow the growth of
several vegetation types which provide habitats for large
numbers of various organisms, from invertebrates to
birds. However, many of these oases and cultivated areas
suffer from water-logging and high salinity. The excess of
soluble salts in these environments have a large influence
on the ecosystem, plant growth and yield (Karimi et al.,
2009).
Salty habitats are the most abundant ecosystem type
along the valley of Oued Righ. Saline soils of various
nature and degree occupy more than 50% of the total area
of the region. These include: salt-affected soils, salt flats
(inland sabkhat and Chotts), saline and sandy soils, oases
salt marshes, high salty and wet soils at margins of saline
Corresponding Author: Mayouf Rabah, Scientific and Technical Research Centre for Arid Areas, Tel.: +213 33 73 42 14;
Fax: +213 33 74 18 15
308
Res. J. Environ. Earth Sci., 4(3): 308-315, 2012
Halophyte vegetation is a characteristic feature of
saline lands. Halophytes are the plants capable of growing
and surviving in the saline environments. A number of
different mechanisms are used by halophytes to achieve
osmotic adjustment, including inorganic ion
accumulation, synthesis or accumulation of organic
compounds and minimizing water loss (Ungar, 1991).
Halophyte communities are of great importance in the
valley of Oued Righ. They play crucial role in wind
prevention and environmental protection. They also offer
habitats for large numbers of various organisms. Many
halophytes are beneficial with respect to economic aspect.
They provide food products; building materials and fuel
wood etc (Squires and Ayoub, 1994; El Shaer, 2008).
However, the vegetation and plant diversity in the
different saline habitats in the region of Oued Righ are,
unfortunately, under severe threats due to environmental
conditions and human impacts, and thus, there is an
urgent need to document the vegetation associated with
these habitats before irreparable damage is caused to these
valuable ecosystems. Plant biodiversity is an important
renewable natural resource, which can be harnessed for
management and sustainable development. Studying the
patterns of plant diversity in salty soils could be very
helpful to better understand the functioning of these
environments (Abd El-Wahab et al., 2008).
Up to now, most of the studies on salt areas in the
great Sahara Desert are just descriptive documentation of
species and their classification (Quzel and Santa, 1963;
Ozenda, 1977; Chehma et al., 2005; Chehma, 2006 ). No
detailed examinations of the vegetation were carried out
to describe various types of plant communities in different
saline areas of Oued Righ. To offset this insufficiency of
floristic knowledge, it is essential to determine and
characterize the vegetation structure and species
composition. Therefore, the main objectives of this study
were to provide a contribution to the vascular flora,
analysis of the structure and life forms of the vegetation,
and quantitative description of different plant
communities from various saline areas along the valley of
Oued Righ. Within each saline area, three different
habitats were identified and studied; saline soil habitats,
subsaline soil habitats, and waterlogged habitats.
Fig. 1: Map of the Valley of Oued Righ with the location of the research localities. 1: Chott Merouane; 2: Chott N Sigha; 3: Oued
Khrouf; 4: Sidi Khlile; 5: Tindla; 6: Lake Ain Zerga; 7: Lake Ayata; 8: Lake Sidi Slimane; 9: Lake Megarine; 10: Lake
Tataouine; 11: Lake Merjaja; 12: Lake Temcine
309
March. The average annual rainfall is approximately 58
mm. The different research localities are shown in Fig. 1.
ATERIALS AND METHODS
Study area: The valley of Oued Righ is located in the
northeastern Sahara desert of Algeria (Low Sahara basin),
which occupies an area of about 600,000 km2. It extends
about 160 km from El Goug in the South to Oum EL
Thiour in the North with an average width ranging
between 30 and 40 km in a south-north direction (Fig. 1).
More exactly the study area lies between 32º53!50" to
34º10!00" north latitudes and between 5º47!50" to
6º10!00" East longitudes. The altitude of this zone varies
from 70 to -27 m above mean sea level. The climate along
this area is arid to hyperarid, characterized by low rainfall
and high rates of evapotranspiration. Daily mean
temperatures vary between 10ºC in the winter to 32ºC in
the summer with August being the hottest month. Rainfall
is generally low and tends to fall between November and
Floristic analysis: A total of 12 sites of saline lands were
surveyed along the valley of Oued Righ. The vegetation
studies were carried out according to the Quadrat method
by following the work of Braun-Blanquet (1932). A
homogenous area, where species abundances and spatial
distributions appeared uniform and where habitat
conditions were constant, was used for the vegetation
description. Three different microhabitats were identified
and studied: saline soil habitats, subsaline soil habitats,
and waterlogged habitats. Within each determined habitat,
two or three representative areas (quadrats) were
randomly selected for sampling. Sixty-seven quadrats
were taken from different microhabitats during the period
of optimal vegetation, i.e., in March and May 2010. The
Table 1: List of plant species recorded in the study area with their families, life forms and floristic regions (Chorotype). The life forms are Ch:
chaemaephytes; Ge: geophytes; He: helophytes; Hm: hemicryptophytes; P: Parasites; Ph: phanerophytes; Th: therophytes. The floristic
regions are COSM: Cosmopolitan; EN: Endemic to Sahara desert; ES: Euro-Sibarian; IT: Irano-Turanian; ME: Mediterranean; SA: SaharoArabian
Family
Plant species
Life forms
Chorotype
Astraceae
Aeluropus littoralis (Gouan) Parl.
Ge
ME
Brocchia cinerea Vis.
Th
SA
Launaea glomerata (Goss.) HooK.
Th
SA
Launaea resedifolia O.K.
Th
ME
Sonchus maritimus L.
Ge
COSM
Brassicaceae
Diplotaxis harra (Forsk.) Boiss.
Ch
ME+SA
Malcomia aegyptiaca Spr.
Hm
SA
Caryophyllaceae
Spergularia diandra (Cuss.) Heldr.
Th
ME+SA+IT
Spergularia salina J. & C. Presl.
Th
ES+IT+ME
Chenopodiaceae
Anabasis articulate Moq.
Ch
SA+IT
Atriplex halimus L.
Ch
ME+SA
Bassia muricata (L.) Asch.
Th
SA+IT
Cornulaca monacantha Del.
Ch
SA
Halocnemum strobilaceum (Pall.) M. Bieb.
Ch
ES+SA+ME+IT
Haloxylon articulatum Boiss.
Ch
SA+ME
Haloxylon schmittianum Pomel.
Ch
EN
Salsola tetragona Delile.
Ch
SA
Salsola tetrandra Forsk.
Ch
SA
Sueda fructicosa L.
Ch
SA
Suaeda mollis (Desf.) Del.
Th
SA
Traganum nudatum Del.
Ch
SA
Convolvulaceae
Cressa cretica L.
Th
ME+IT
Frankeniaceae
Frankenia pulverulenta L.
Th
ME+IT+ES
Juncaceae
Juncus maritimis Lam.
He
SA+IT
Orobanchaceae
Cistanche violaceae (Desf.) Beck.
P
IT+ME+SA
Plantaginaceae
Plantago ciliata Desf.
Th
SA
Plantago coronopu L.
Th
SA+IT
Plumbaginaceae
Limonium pruinosum (L.) Chaz.
Ch
SA
Limonium echioides L.
Hm
ME
Limoniastrum guyonianum Dur.
Ph
EN
Poaceae
Phragmites comminus Trin.
He
COSM
Cynodon dactylon (L.) Pers.
Ge
COSM
Tamaricacea
Tamarix gallica Webb.
Ph
SA
Tamarix articulata Vahl.
Ph
SA
Zygophyllaceae
Fagonia Glutinosa Delile.
Ch
SA
Fagonia latifolia Delile.
Ch
SA
Nitraria Retusa (Forssk.) Asch.
Ph
SA
Zygophyllum album L.
Ch
ME+SA
310
quadrat size was estimated by means of minimal area and
was determined as 400 m2 (20 m×20 m) for Saline and
subsaline Soils vegetation and 30 m2 (3 m×10 m) for the
waterlogged habitats. For each quadrat group representing
a habitat type, the quantitative account of vegetation such
as cover, density and frequency were calculated.
Importance Value Index (IVI) was obtained for each
species that was calculated by adding relative density,
relative frequency and relative cover percentages (BraunBlanquet, 1965). Species identification and floristic
categories were determined according to Quzel and Santa
(1963) and Ozenda (1977). The life forms were
determined according to Raunkiaer (1934).
Fig. 2: Spectrum of life forms for the halophyte species
recorded in the study area. Ch: chaemaephytes; Ge:
geophytes; He: helophytes; Hm: hemicryptophytes; P:
Parasites; Ph: phanerophytes; Th: therophytes
RESULTS
A total of 38 halophytic species within 29 genera and
13 families of flowering plants were recorded in the
various habitats of the valley (Table 1). Dicotyledons
comprised 92.1% of the total (35 species in 11 families),
while the remainder consisted of 3 monocotyledons
species (2 families). The family with the highest number
of species was Chenopodiaceae, with 12 species, followed
by Asteraceae (5 species) and Zygophyllaceae (4 species).
Regarding the life forms spectra (Fig. 2), chamaephytes is
the predominant life-form and constitute 39.5% of all
recorded species, followed by therophytes (29%),
phanerophytes (10.5%), geophytes (7.9%),
hemicryptophytes (5.3%), cryptophytes (5.3%), and
parasites (2.5%). The phytogeographical distribution
(chorotype) of the plant species is given in (Fig. 3),
showing that the majority of the species are of SaharoArabian distribution (42.1% mono-regionals+21% biregionals+15.8% pluri-regionals), followed by
Mediterranean species (7.9% mono-regionals+13.1% biregionals+21.1% pluri-regionals). Two species were
endemic to great Sahara Desert (Haloxylon schmittianum
and Limoniastrum guyonianum).
Quantitative investigations were carried out to
describe the various types of halophyte vegetation. In
fact, natural saline areas of the valley of Oued Righ can
be divided ecologically into three different microhabitats,
depending on the soil salinity and water availability:
saline soils, subsaline soils, and waterlogged habitat.
Species composition in the different habitats showed
differences in species richness. The highest species
richness was recorded from Subsaline habitat.
Waterlogged habitat possessed less number of species (17
species; 44.7%) as compared to the rest of habitats. For
the saline soil habitats, the general coverage rate was
between 25 to 45%. The vegetation of these habitats
consisted mainly of perennial semi-shrubby plants 1060cm in height. This vegetation was floristically
dominated with Halocnemum strobilaceum species which
had Absolute frequency (AF) of 100, Absolute cover
Spices frequency
50
Mono-regionals
Bi-regionals
Pluri-regionals
40
30
20
10
Others
COSM
SA+IT
SA+IT
SA+ME
E
IT
ME
SA
00
Chorotypes
Fig. 3: Phytogeographical distribution of the plant species of
the different saline habitats. SA: Saharo-Arabian; ME:
Mediterranean; IT: Irano-Turanian; E: Endemic to
Sahara desert; SA+ME: Saharo-Arabian-Mediterranean;
SA+IT: Saharo-Arabian-Irano-Turanian; ME+IT:
Mediterranean-Irano-Turanian; COSM: Cosmopolitan.
Others include Saharo-Arabian-Mediterranean-EuroSiberian, Saharo-Arabian-Mediterranean-IranoTuranian, and Saharo-Arabian-Mediterranean-IranoTuranian-Euro-Siberian
(AC) of 0.52 and Importance value index (IVI) of 112.2
among all the observed species (Table 2). The Coassociated characteristic species in this high salty areas
were Tamarix gallica, Aeluropus littoralis and Sueda
fructicosa with IVI of 28.8, 21.92 and 18.12, respectively.
The other associated species such as Zygophyllum album,
Phragmites comminus, Limoniastrum guyonianum,
Frankenia pulverulenta, and Juncus maritimis etc. had
ecologically a lower significant representation in this
vegetation. In the habitats of subsaline soil, the coverage
rate ranged between 35 to 50%. Annual herbaceous plants
311
Table 2:Absolute density, frequency and cover (numbers per 100 m2), their relative density, frequency, cover (%) and importance value index (IVI)
of the halophyte species of the three saline habitats. Species are ranked in order of decreasing importance value. (AD: Absolute density; AF:
Absolute frequency; AC: Absolute cover; RD: Relative density; RF: Relative frequency; RC: Relative cover; IVI: impotence value index).
Species
-------------------------------------------------------------------------------------------------------------------------Saline soil habitats
AD
AF
AC
RD
RF
RC
IVI
1.280
100
0.520
44.5
13.5
54.2
112.2
0.094
66
0.160
3.27
8.93
16.6
28.80
Aeluropus littoralis (Gouan) Parl.
0.380
46
0.024
13.2
6.22
2.50
21.92
Sueda fructicosa L.
0.300
26
0.040
10.45
3.51
4.16
18.12
0.080
60
0.050
2.78
8.11
5.20
16.09
0.210
40
0.004
7.31
5.41
0.41
13.13
0.020
46
0.033
0.69
6.22
3.43
10.34
0.090
33
0.020
3.13
4.46
2.08
9.67
0.070
33
0.010
2.43
4.46
1.04
7.93
0.030
33
0.020
1.04
4.46
2.08
7.58
0.010
26
0.022
0.34
3.51
2.29
6.14
0.070
20
0.002
2.43
2.70
0.20
5.33
0.015
20
0.020
0.52
2.70
2.08
5.30
Anabasis articulate Moq.
0.012
20
0.020
0.41
2.70
2.10
5.21
Traganum nudatum De
l.0.02
26
0.003
0.69
3.51
0.30
4.50
0.070
13
0.001
2.43
1.75
0.10
4.28
Atriplex halimus L.
0.010
26
0.002
0.34
3.51
0.20
4.02
Cressa cretica L.
0.010
20
0.002
0.34
2.70
0.20
3.24
0.010
20
0.002
0.34
2.70
0.20
3.24
0.010
20
0.002
0.34
2.70
0.20
3.24
0.035
13
0.001
1.21
1.75
0.10
3.06
0.030
13
0.001
1.04
1.75
0.10
2.89
0.010
13
0.002
0.34
1.75
0.20
2.29
0.010
6.0
0.001
0.34
0.81
0.10
1.25
Subsaline soil habitats
0.820
86.7
0.250
22.84
5.83
32.5
61.17
Sueda fructicosa L.
0.540
940
0.150
15.04
0.32
19.23
34.59
0.305
730
0.067
8.49
4.90
8.58
21.97
0.310
800
0.050
8.63
5.37
6.41
20.41
Traganum nudatum Del.
0.254
800
0.035
7.07
5.37
4.48
16.92
0.084
66.6
0.035
2.39
4.47
4.48
11.34
Brocchia cinerea Vis.
0.095
80.0
0.008
2.64
5.37
1.02
9.03
0.080
80.0
0.090
2.22
5.37
1.15
8.74
0.250
20.0
0.003
6.69
1.34
0.38
8.41
Malcomia aegyptiaca Spr.
0.078
60.0
0.015
2.17
4.03
1.92
8.12
Aeluropus littoralis
0.230
6.6
0.010
6.40
0.44
1.28
8.12
Bassia muricata (L.) Asch.
0.096
60.0
0.006
2.67
4.03
0.76
7.46
0.035
60.0
0.006
0.97
4.03
0.76
5.76
0.027
46.6
0.004
0.75
3.13
0.51
4.39
Cornulaca monacantha Del.
0.018
46.7
0.004
0.50
3.14
0.51
4.15
Launaea resedifolia O.K.
0.014
46.7
0.004
0.38
3.14
0.51
4.03
Launaea glomerata (Goss.) HooK.
0.028
40.0
0.004
0.77
2.68
0.51
3.96
0.070
20.0
0.002
1.94
1.34
0.25
3.53
Plantago ciliata Desf.
0.022
33.3
0.003
0.61
2.23
0.38
3.22
Anabasis articulate Moq
0.012
33.4
0.003
0.33
2.24
0.38
2.95
0.008
33.3
0.003
0.22
2.23
0.38
2.83
Atriplex halimus L.
0.005
33.4
0.003
0.13
2.24
0.38
2.75
0.013
26.6
0.002
0.36
1.78
0.25
2.39
0.013
26.6
0.002
0.36
1.78
0.25
2.39
Plantago coronopu L.
0.008
26.6
0.002
0.22
1.78
0.25
2.25
Haloxylon articulatum Boiss.
0.007
26.6
0.002
0.19
1.78
0.25
2.22
0.017
20.6
0.002
0.47
1.38
0.25
2.10
Diplotaxis harra (Forsk.) Boiss.
0.002
26.7
0.002
0.05
1.79
0.25
2.09
0.015
20.0
0.002
0.41
1.34
0.25
2.00
Fagonia latifolia Delile.
0.005
20.0
0.001
0.13
1.34
0.12
1.59
Cistanche violaceae (Desf.) Beck.
0.007
20.0
0.002
0.19
1.34
0.25
1.78
Haloxylon schmittianum Pomel.
0.006
13.3
0.001
0.16
0.89
0.12
1.17
0.003
13.3
0.001
0.08
0.89
0.12
1.09
0.002
13.4
0.001
0.05
0.90
0.12
1.07
0.001
13.3
0.001
0.002
0.89
0.12
1.01
Waterlogged habitats
7.420
100
0.71
49.5
14.5
51.1
119.1
5.710
93
0.55
38.1
13.5
39.5
91.10
0.865
74
0.06
5.77
10.3
4.31
20.41
Aeluropus littoralis
0.625
62
0.01
4.16
9.10
0.71
13.97
0.070
66
0.02
0.46
9.59
1.43
11.48
312
Table 2: (Countinue)
Sueda fructicosa L.
Cressa cretica L.
Atriplex halimus L.
0.090
0.097
0.040
0.037
0.012
0.006
0.005
0.010
0.002
0.002
0.001
0.002
40
40
40
33
33
26
20
20
13
13
60
60
0.010
0.004
0.004
0.003
0.003
0.002
0.002
0.001
0.001
0.001
0.001
0.001
were mainly found in this vegetation type. The dominant
species were L. guyonianum and S. fructicosa which had
AF of 86.7 and 94, AC of 0.25 and 0.15 and IVI of 61.17
and 34.59, respectively. The co-dominant characteristic
species were H. strobilaceum, Z. album, Traganum
nudatum, and Nitraria Retusa with IVI of 21.97, 20.41,
16.92, and 11.34, respectively. Many other species were
associated within these vegetation type such as Brocchia
cinerea, Salsola tetragona, Juncus maritimis, Malcomia
aegyptiaca, Aeluropus
littorali, Bassia muricata,
Tamarix gallica, Salsola tetrandra and Cornulaca
monacantha etc with IVI ranged between 9.03 to 1.01
during the period of study (Table 2). The waterlogged
areas (aquatic macrophytes) were characterized by a
dense vegetation cover (75 to 85%). Phragmites
comminus and Juncus maritimis were the dominant
species (Table 2). They attained the highest values of AF
(100, 93), AC (0.71, 0.55) and IVI (119.1, 91.1) among
the recorded species. The associated characteristic species
were H. strobilaceum, A. littoralis, T. gallica, Z. album,
S. fructicosa, Sonchus maritimus and Limonium echioides
with IVI of 20.41, 13.97, 11.48, 7.12, 6.73, 6.35 and 5.25,
respectively. Other associated species were rarely found
among the dominant plants such as Cressa cretica,
L. guyonianum, Spergularia salina, Frankenia
pulverulenta, Suaeda mollis, Atriplex halimus, Tamarix
articulate, Spergularia diandra.
5.80
5.81
5.81
4.79
4.79
3.77
2.90
2.90
1.88
1.88
0.87
0.80
10.7
0.28
0.28
0.21
0.21
0.14
0.14
0.07
0.07
0.07
0.07
0.07
17.12
6.73
6.35
5.25
5.08
3.95
3.07
3.01
1.96
1.96
0.95
0.88
addition, few ephemerals are also observed growing in
these habitats like Brocchia cinerea, Bassia muricata,
Launaea glomerata, Launaea resedifolia, and Malcomia
aegyptiaca. These ephemerals come up during the rainy
season, complete their life cycle before the advent of
summer.
Phytogeographical relations have a significant
influence on species diversity as they largely determine
the stock of species available in the past and present for
inhabiting the area (Abd El-Wahab et al., 2008). Analysis
of the floristic data revealed that the Saharo-Arabian
elements are more common than the other floristic
elements in the research area. This is due to the fact that
the study area is located in the Algerian Sahara which is
a part of the Saharo-Arabian phytogeographical region
(Zohary, 1973). Furthermore, information regarding the
life form of plant species may help in assessing the
response of vegetation to variations in environmental
factors (Ayyad and EI-Ghareeb, 1982). In the present
study, chamaephytes is the predominant life-form. The
high percentage of chamaephytes may be related to their
ability to resist drought and salinity (El-Bana et al., 2002).
Several studies on the correlation between the soil
characteristics and the vegetation composition had
discussed the significant relationship between the soil
physicochemical characteristics and the species
composition (Youssef et al., 2009). The variation in
density, frequency and abundance between the species
may be attributed to habitat differences and species
characteristics for adaptation (Youssef and Al-Fredan,
2008). Overall, salinity, pH, moisture and available
nitrogen are the major soil factors responsible for
variations in the pattern of halophytic vegetation. Thus,
halophytic vegetation could be used as an indicator for
soil salinity, water content and nutrient content in saline
areas (Li et al., 2008). The results of this study confirm
that the distribution of halophytic vegetation types is most
strongly correlated with soil salinity and moisture. The
vegetation of saline soils which covers the heavily saline
areas are characterized by very open halophyte
vegetation, mainly with the extreme halophyte
Halocnemum strobilaceum. The low species diversity of
this vegetation type is related to the high salt
concentration. The vegetation of subsaline soils is well-
DISCUSSION
This study is presented to describe the biodiversity of
natural Saline Habitats of the valley of Oued Righ. Three
distinct microhabitats were recognized based on the soil
characteristics as follows:
C
C
C
0.600
0.640
0.260
0.250
0.080
0.040
0.030
0.067
0.013
0.013
0.006
0.013
Saline soil habitats
Subsaline soil habitats
Waterlogged habitats
with the exception of the submerged aquatic macrophytes,
which characterized by a relatively dense and uniform
vegetation cover, halophyte vegetation of Oued Righ
region is sparse consisting mainly of dwarf shrubs and
perennial herbs capable of salinity and drought resistance.
Trees are few and scattered. Tamarix articulata is the
tallest of tree with maximum height attained 4-6m. In
313
Ayyad, M.A. and R.E. EI-Ghareeb, 1982. Salt marsh
vegetation of the western Meditteranean desert of
Egypt. Vegetatio, 49: 3-19.
Braun-Blanquet, J., 1932. Plant Sociology: The study of
Plant Communities., Translated. In: Fuller, G.D. and
H.S. Conard (Eds.), Authorized English Translation
of Pflanzensoziologie McGraw-Hill, New York.
Braun-Blanquet, J., 1965. Plant Sociology: The Study of
Plant Communities. Hafner Publ. Comp., New York.
Chehma, A., M.R. Djebar, F. Hadjaiji and L. Rouabeh,
2005. Étude floristique spatio-temporelle des
parcours sahariens du Sud-Est algérien. Sécheresse,
16(4): 275-285.
Chehma, A., 2006. Catalogue des plantes spontanées du
Sahara septentrional algérien. Ed: Dar Elhouda Ain
M’lila, Alger.
El-Bana, M.I., A.A. Khedr and P. Van Hecke and
J. Bogaert, 2002. Vegetation composition of a
threatened hypersaline lake (Lake Bardawil), North
Sinai. Plant Ecol., 163: 63-75.
El-Bana, M.I., I. Nijs and A.A. Khedr, 2003. The
importance of phytogenic mounds (nebkhas) for
restoration of arid degraded rangelands in Northern
Sinai. Restoration Ecol., 11: 317-324.
El Shaer, H., 2008. Potential Rate of Sabkhas in Egypt:
An Overview. In: Ashraf, M., M. Ozturk and
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Springer, Netherlands, 44: 221-228.
Grattan, S.R. and C.M. Grieve, 1999. Salinity-mineral
nutrition relation in horticultural crops. Sci. HorticAmesterdam, 78: 127-157.
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2009. Effects of long-term salinity on growth and
performance of two pistachio (Pistacia L.)
rootstocks. Aust. J. Basic Appl. Sci., 3: 1630-1639.
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salinity and temperature on the germination of
Kochia scoparia. Wetland Ecol. Manage., 9: 483-489.
Li, W.Q., L. Xiao-Jing, M. Ajmal Khan and B. Gul, 2008.
Relationship between soil characteristics and
halophytic vegetation in coastal region of north
china. Pak. J. Bot., 40: 1081-1090.
Ozenda, P., 1977. Flore du Sahara. CNRS, Paris.
Quzel, S. and S. Santa, 1963. Nouvelle Flore de l’Algerie
et des Regions Desertique Méridionales. CNRS,
Paris.
Raunkiaer, C., 1934. The Life forms of Plants and
Statistical Plant Geography. Clarendon Press,
Oxford.
Remon, E., J.L. Bouchardon, B. Cornier, B. Guy,
J.C. Leclerc and O. Faure, 2005. Soil characteristics,
heavy metal availability and vegetation recovery at a
former metallurgical landfill: Implications in risk
assessment and site restoration. Environ. Pollut., 137:
316-323.
developed, more diverse, and the most important
vegetation type of the natural saline areas. The dominant
species of this vegetation type which develops on soils
with less salt content are Limoniastrum guyonianum and
Sueda fructicosa. In the woterlogged habitats, the
dominant species are monocot perennials belonging to the
genera Phragmites and Juncus. Phragmites comminus
forms a vast, dense and uniform reed swamp. Reeds tend
to form a dense canopy which makes the germination and
growth of other species more difficult. This often leads to
reduce the species diversity (Shaltout and El-Shiekh,
1993). On the other hand, Reed swamps are the most
important habitats for a variety of wildlife, especially for
migratory birds (Serag et al., 1999).
Several authors have pointed out the importance of
halophyte species (Aronson, 1989; Squires and Ayoub,
1994; El Shaer, 2008). Although halophyte communities
in desert regions are not as high in biological diversity as
those in other areas, they play an important role in the
ecological and evolutionary dynamics of arid ecosystems
because they are biologically important for both
ecosystem structure and process (El-Bana et al., 2003).
In addition to their potential use as pastures, building
materials, medicinal plants, fuel wood, fertilizers, and
even sequestration of CO2 (El Shaer, 2008), Natural
spontaneous halophytes can be very effective in
reforestation and ecological recovery of saline areas.
These indigenous species are well adapted to
environmental conditions and capable to colonize highly
saline soils. In this context, for an effective
phytostabilisation strategies and sustainable land
management, it is important to use native plants for
phytoremediation because these plants are often better in
terms of survival, growth and reproduction than plants
introduced from other environment (Remon et al., 2005).
Phytomelioration by plantings on saline soils leads to a
more rapid closure of the vegetation cover and helps to
minimize the widespread negative effects of salt
desertification (Wuncherer et al., 2005). Therefore,
studying natural halophytes and the complex physiology
and ecology of the indigenous species and populations is
useful in increasing our understanding of the processes
and dynamics of saline ecosystems.
REFERENCES
Abd El-Wahab, R.H., M.S. Zaghloul, W.M. Kamel and
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Serag, M.S., A.A. Khedr, M.A. Zahran and A.J. Willis,
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Ungar, I.A., 1991. Ecophysiology of Vascular
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315

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