Floristic Composition of the Halophilic and Salt-Resistant Plant Population in Hammam-Boughrara (Oran-Algeria)
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Vol.2, No.2, 96-108 (2012) Open Journal of Ecology http://dx.doi.org/10.4236/oje.2012.22012 Floristic composition of the halophilic and salt-resistant plant population in Hammam-Boughrara (Oran-Algeria) Amel Taleb-Bendiab Sari-Ali*, Noury Benabadji, Mohamed Bouazza Department of Biology and Environment, Faculty of Natural Sciences and Life and Earth Sciences and the Universe, Tlemcen Uni- versity, Tlemcen, Algeria; *Corresponding Author: [email protected] Received 10 February 2012; revised 11 March 2012; accepted 10 April 2012 ABSTRACT studied by Simonneau [1], Dubuis and Simonneau [2,3] and Quézel and Simonneau [4], and its distribution re- This phyto-ecological study is on halophilic and lates to the soil salinity. The dominant plants are annual salt-resistant vegetation of Oran region. The semi- or perennial Salsolacea, forming either pure populations arid and sometimes arid climate has been defined and confirmed from a bioclimatic point of view. or associations, comparable to those described in the The pedological approach used shows a soil with south of France [5]. sandy to silty-sandy texture, favoring regression In the Hammam-Boughrara region, vast areas of both Tafna wadi shores, unsuitable for cultivation, are covered of the vegetation and a halophilic vegetation set + up. In this study, we analyze the floristic com- with halophytes. These soils, saturated with Na ions, are position of the northern region of Hammam classified among Solonchak soils [6]. Their appearance is Boughrara using multiple floristic surveys con- due to the phreatic water which deposits its salts on the ducted at three stations along the Tafna wadi. surface during evaporation [2,7]. Dominated by Mediterranean and Saharo-Sin- Knowledge of the natural vegetation, as a reflection of dian elements, the relatively poor flora (88 spe- environmental conditions, should allow a diagnosis of the cies in total) is biologically characterized by a clear first face plant in these ecosystems. dominance of therophytes (>33%) and chama- The works in the region remain somewhat fragmented. ephytes (>19%) to the detriment of phanero- We intend contribute floristic surveys that may be useful. phytes. The interpretation of the Oran halophilic populations is possible and effective in light of pre-forest formations Keywords: Phyto-Ecology; Salt-Resistant derived from, because of the strong anthropic pressure Vegetation; Halophilic Vegetation; Botanical exerted in the region. The area was also affected by Characterization; Bioclimate; Hammam Boughrara; drought from 1970 to 2000. Oran (Algeria) Through the various works done on this region [8,9], we have tried to identify the halophytes phytoecology aspects in the Northwest of Algeria (North of Hammam- 1. INTRODUCTION Boughrara). Can these aspects give us some suggestions The Maghreb has one of the most remarkable floras of for improving the disrupted flora capital? Do halophilic the Mediterranean basin. This may explain its climatic, populations expanse exclusively on the North banks of Tafna wadi? In an attempt to answer to these questions, geographic and geological diversity. Algeria in general we will deal in this paper successively through: and Oran in particular, is an area characterized by sig- Description of the physical environment; nificant plant diversity. Bioclimatic and edaphologic characters; For a long time, the flora and landscape of this region Floristic analysis. have been coveted and reshaped by the cultivation and grazing. The area is located solely in a semi-arid and arid 2. SITES AND METHODS bioclimate, with a temperate winter; the area is also sub- ject to problems related to continentality in western Al- 2.1. Location and Choice of Sites of Study (Figure 1) geria. The vegetation of the Oranian saline soils has been The study area is located in western Algeria and be- Copyright © 2012 SciRes. OPEN ACCESS A. Taleb-Bendiab Sari-Ali et al. / Open Journal of Ecology 2 (2012) 96-108 97 longs administratively to the wilaya of Tlemcen. It is 1.5 mm in July). This shows important variability be- naturally confined by the Traras Mountains on the north- tween months and places. west and the Tlemcen Mountains on the south. The Ham- The climate is semi-continental with a temperature range mam Boughrara municipality (study area) is limited ad- of about 27˚C. January is the coldest month (9.5˚C), and ministratively: August the hottest (29.2˚C) [11]. To the west by the municipalities of Maghnia and The pluviothermic Emberger quotient (Q2) [12] per- Djabala. mits the halophilic populations to establish in the lower To the south by the municipalities of Remchi and semi-arid and higher arid bioclimates with cool to tem- Sabra; perate winter variation. To the east by the municipalities of Hennaya and Tlemcen; 2.3. Soils of the Region And to the north by those of Zenata and Remchi. Soil studies, in North Africa in general and in this par- The choice of stations considered to be representative ticular region, were carried out by Simonneau [13], Ru- was made to reflect the greatest plant diversity of the study ellan [14], Pouget [15], Alcaraz [16], Aimé [17] and area and was directed by the presence of salt tolerant Benabadji et al. [18]. populations. Three sites were selected through a stratified The analytical results obtained on some soil samples sampling: Zenata, Remchi and Hammam Boughrara in the three sites show: (Table 1). A sandy texture in Hammam Boughrara (72% sand) These sites differ from each other by geographic loca- and silty-sandy texture (17% silt, 68% sand) in Rem- tion, topography, soil, anthropogenic factors and vegetal chi and Zenata. diversity. A total lime content between 2.52% and 18.80% in the region of Remchi. Hammam Boughrara soils have 2.2. Bioclimatic Situation higher CaCO3 content (above 25%). Belonging to the Mediterranean bioclimate, the northern The pH is basic in all the sites. It also records a value region of Hammam Boughrara is characterized by dry greater than 7 in all the samples. periods that can last 6 to 7 months. The bioclimate of the Salinity (electrical conductivity) varies from slightly region has been studied by Ghezlaoui [8,10] and Bem- salty to salty. The minimum thresholds are reached in moussat [11]. The area receives winter Mediterranean Zenata region (0.7 and 0.8 mS/cm), the upper limits drizzling rains which last longer than those in the summer. are obtained in Hammam Boughrara with 1.21 mS/cm. March and April rains are heavy and frequent, whereas Organic matter is relatively low for all stations (0.104% January and February rainfalls are lighter, but more fre- to 2.21%. quent. The color according to the Munsell code ranges from Annual rainfall varies between 280 mm and 300 mm 5YR 5/6, 7.5 YR 6/6 and 10YR 6/4 for all the sta- (with a maximum of 49 mm in March and a minimum of tions. 0 740 km Figure 1. Geographical location of study sites. Copyright © 2012 SciRes. OPEN ACCESS 98 A. Taleb-Bendiab Sari-Ali et al. / Open Journal of Ecology 2 (2012) 96-108 3. METHODOLOGY is dominated by Atriplex halimus, Salsola vermiculata, Suaeda fruticosa, Lygeum spartum and Arthrophytum Floristic Surveys scoparium. It is characteristic of Atriplico halimi- The vegetation of the study station indicates a pre- Suaedetum fruticosae ass. nov. in Aimé [17] and Salsolo- forest and halophilic physiognomy, except on some moun- Peganion alliance. The rate of recovery varies from one tain slopes located further north (Traras Mountains). In place to another. In depressions, these populations reach this area, rainfalls may reach 400 mm annually. It also 30% and become rare on the wadi beds. Malva sylvestris, contains degraded remnant forests, formed by Pinus Ziziphus lotus, Pallenis spinosa and companion species halepensis, Juniperus oxycedrus and Pistacia atlantica. are poorly represented in the surveys. Floristic surveys were conducted in spring periods, in Remchi station, Tafna wadi (Table 2 in appendix) spaces occupied by the Chenopodiaceous, which spread At first glance, in this clump, an asymmetry emerges, over the borders of Tafna wadi and near cultivations. resulting in a wooded, slightly inclined station and an- The surface records must be sufficient to obtain almost other with steep cleared slopes. all the species present, in the floristically homogeneous Surveys conducted along the banks of Tafna wadi show station, corresponding to the minimum area [19]. a diversified landscape infiltrated by pre-forest popula- According to Quézel et al. [20] areas are from 100 to tions (Teucrium polium, Ampelodesma mauritanicum, 400 m2 for forest communities, from 50 to 100 m2 for the Cistus albidus and Thymus ciliatus. Classes of Thero- scrubland formations and 20 to 50 m2 for herbaceous Brachypodietea [27] and Stellarietea mediae [28] are vegetation. For this survey we deliberately chose a 100 m2 well represented with the following species: Muricaria area (minimum area). prostrata, Aegilops triuncialis, Astragalus pentaglottis, During the survey, each identified species was affected Salvia verbenaca, Calendula arvensis, Plantago ovata by two indices; the first reflects the abundance-domi- etc. These species are mostly annual therophytes said nance and the second sociability. The presence and the nitratophiles. The use of fertilizers eliminates the most number of individuals were also noted, using the Braun sensitive species and promotes the development of the Blanquet method [21]. nitratophilic ones. In this region, greenhouse crops are The determination of biological types of the 88 species taking considerable hold. We distinguished these species, recorded was based on the Raunkiaer method [22]. All life mixed in with those belonging to the Salsolatea ver- forms were considered, regardless of the different subdi- miculatae class, the Atriplico halimi-Suaedetum frutico- visions for the size variation, morphology and arrange- sae ass. nov. in Aimé [17] association and the Salsolo- ment of the various organs.