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N. BOUCHENEB, S.S. BENHOUHOU 72 rocky substrate with boulders and crevices, for an altitude varying between 1380 and 1600 m. This association is characterised physiognomically by Rhus tripartita (Ucria) Grande and Olea europaea subsp. laperrinei (Table 1). On boulders, talus scree and crevices Olea europaea subsp. laperrinei is dominant. Species with an average frequency are all chasmophiles belonging to the Aervo-Fagonion Quézel 1965 (Aerva javanica (Burm. F.) Juss. ex Schult., Aizoon canariense L., Anabasis articulata (Forssk.) Moq., Fagonia bruguieri DC., F. longispina Batt., Forsskaolea tenacissima L., Helianthemum ruficomum (Viv.) Spreng.) and to the Acacio- Panicion (Acacia ehrenbergiana Hayne, Heliotropium bacciferum Forssk., Pulicaria undulata (L.) C.A. Mey. Trichodesma africanum (L.) R. Br.). This association is close to the Olea europaea subsp. laperrinei-Crambe kralikii Coss. association described by Quézel (1965) at much higher altitudes (1800 to 2400 m), which is related to the Lavanduletea antineae Quézel 1965. The absence of characteristic species belonging to the Lavanduletea antineae Quézel 1965 such as Lavandula antineae, Ballota hirsuta Benth., Erigeron trilobus (Decne.) Boiss., Globularia alypum L., Hyparrhenia hirta (L.) Stapf and Crambe kralikii, all high altitude species that first appear at 1800 m, leads us to consider another syntaxonomical hierarchy. When considering the floristic list, our association is best related to the Aervo-Fagonion, the Aervo-Fagonietalia and the Asterisceto-Forsskaoletea Quézel 1965. The unique assemblage of chasmophiles, confined to rocky terrain for altitudes ranging between 1400 and 1600 m and described for the first time in the north and north-eastern regions of Tamanrasset is sufficiently distinctive to require the definition of a new association – one floristically characterised by Rhus tripartita and Olea europaea subsp. laperrinei. The Cassia aschrek and Panicum turgidum community This association corresponds to the floristic group E2 identified by the correspondence analysis (Figure 4). It is represented by sixteen relevés taken from wadi beds and nearby terraces as well as from outwash zones. Soil substrates varied from sandy-gravelly to sandy-rocky textures. The altitude at which the relevés were taken varied between 1000 and 1500 m. This association was observed in wadi Taddadine, Ouezzene in the Ahléheg massif, wadi Tit in the Ti-n-Tourdi massif, wadi Tafirt in the Tahelgha massif and wadi Tehart, in the Alemeda massif (Figure 3). According to the physiognomically dominant plants, this association corresponds to the Acacia-Panicum desertic savannah first described by Maire (1940). Vegetation is characterised by the dominance of trees and shrubs among which the most important ones are Acacia ehrenbergiana, Acacia tortilis subsp. raddiana (Savi) Brenan and Maerua crassifolia Forssk. (Table 2). Detailed analyses of the floristic composition of this association showed that the characteristic species belonging to the Acacio-Panicion alliance, particularly Acacia ehrenbergiana, Acacia tortilis subsp. raddiana and Zilla spinosa (L.) Prantl, have high frequency scores. Species characteristic of the Pergulario-Pulicarietea Quézel 1965 are also well represented with frequencies as high as IV. Characteristic species of our association are the same as those proposed by Quézel (1965) to define the Cassia aschrek (Senna italica Mill.) and Panicum turgidum Forssk. community. Likewise characteristic species of the Salvia chudaei Batt. & Trab. sub-association are: Salvia chudaei, Artemisia campestris L., Deverra scoparia Coss. & Durieu subsp. scoparia and Cymbopogon schoenanthus (L.) Spreng. Considering the very close similarity of the characteristic species for the different units of the phytosociological framework given for the Acacia-Panicum desertic savannah, the vegetation type documented in Table 2 corresponds to the association of Cassia aschrek-Panicum turgidum Quézel 1965 and the Salvia chudaei sub-association. Field observations showed that Deverra scoparia subsp. scoparia has a much higher frequency than Salvia chudaei, which strongly supports proposing Deverra scoparia subsp. scoparia to characterise the sub-association rather than Salvia chudaei. The ecological optimum of Deverra scoparia subsp. scoparia is around 1300 m and has also been observed in the Tassili at similar altitudes (Leredde 1957; Benhouhou et al. 2003a). ecologia mediterranea – Vol. 38 (2) – 2012
Table 2 – The Cassia aschrek-Panicum turgidum association. ecologia mediterranea – Vol. 38 (2) – 2012 Plant communities in the Tamanrasset region, Ahaggar, Algeria Quadrat number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Area (m²) 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 Total cover (%) 40 30 40 20 25 30 20 15 35 10 20 40 20 20 15 40 Altitude (m) 1330 1120 1500 1510 1510 1240 1410 1330 1480 1400 1380 1530 1380 1460 1340 1500 Number of Taxa 23 10 18 25 14 10 19 6 17 18 23 27 11 14 13 13 Caracteristics of the association CP Senna italica (Cassia aschrek) + + + + + . + . + + . + . + + 3 V Panicum turgidum . + + + . . + + + + + + + + . . IV Caracteristics of the sub association of Salvia chudaei Quézel 1965 Deverra scoparia subsp. scoparia 2 + 1 1 2 1 1 + 2 1 1 + + + + + V Artemisia campestris + 2 2 1 + 2 1 + . . . . . . . . III Salvia chudaei . . . . . . + . + + . . . + . . II Caracteristics of the Acacio-Panicion Quézel 1965 Zilla spinosa + + . + + + + + . + + + + + + . V Acacia tortilis subsp. raddiana 3 . 3 . . 2 2 + . + + . + + . + IV Acacia ehrenbergiana . . . + . . 1 . 2 2 2 . + + 1 . III Maerua crassifolia . . + . . . . . + . . . . + . . II Ziziphus lotus + . . . 3 . . . . . . . . . . . I Caracteristics of the Pergulario-Pulicarietea Quézel 1965 Pulicaria crispa 1 2 + + + + + + . . + . + + . + IV Trichodesma africanum . . + + + . + . + + + + + + . . IV Pulicaria undulata + + . + . + . . . . + + + . + . III Heliotropium bacciferum . . . + . . + . . . + + + . + . III Echium humile + . . + . + + . . . + + . . . . III Morettia canescens . . . + . + . . . . + + . . . . II Citrullus colocynthis + . . . . . . . . . + . . . + . II Centaurea pungens . . . + . . . . . . . . . . . + I Pennisetum divisum . . . . . . . . . . . + . . + . I Pergularia tomentosa . . . . + . . . . + . . . . . . I Transgressives of the Asterisceto-Forsskaoletea Quézel 1965 Aerva javanica + + . . . + . . + + + + . + . . III Anabasis articulata . . + + . . . . + + + 3 . . . . III Fagonia bruguieri + . . + . . . . . . . + + . + . III Forsskaolea tenacissima + . . . . . . . . . + . . . + . II Lotus roudairei + . . . . . . . . . . + . . . . I Psammophils Aizoon canariense + . + + + . + . + . + 2 . . + + IV Cynodon dactylon + + + . + + + . . + + . + . + 1 IV Cleome africanum + . . + + . . . . . + + . . . . III Tribulus terrestris + . + + . . + . . . + . . . . . III Matthiola livida + + + . . . + . + + . . . . . . III Paronychia arabica . . . + + . . . . . + + . . . + III Cucumis pustulatus . . + . . . + . + + . . . . . . II Mollugo cerviana + . + . . . + . . . . . . . + . II Asphodelus tenuifolius . . . + . . . . . . . + . . . + II Hippocrepis multisiliquosa . . . + . . . . . . . + . . . + II Matricaria pubescens + . . . . . . . . . . + . . . 2 II Euphorbia granulata Chasmophils + . . + . . . . . . . + . . . . II Cymbopogon schoenanthus . . . . . . . . + + + + . + . . III Reseda villosa . . . + + . . . . . + + . . . + III Rhus tripartita . . + . . . . . 1 + . . . + . . II Ephedra altissima . . + . + . . . + + . . . . . . II Periploca laevigata . . . . . . . . + + . . . + . . II Atractylis aristata + . . . . . . . . . . + . . . . I Astragalus mareoticus . . . + . . . . . . . + . . . . I Helianthemum hirtum . . . + . . . . . . . + . . . . I Stipagrostis obtusa . . . . . . . . . . + + . . . . I Salvia aegyptiaca . . + . . . + . . . . . . . . . I Asteriscus graveolens . . . . . . . . + . . . . . . + I Additional species: Acacia laeta + (14), Acacia scorpioides 2 (4), Bassia muricata + (11), Calotropis procera + (8), Chrozophora brocchiana + (13), Cocculus pendulus + (11), Commicarpus stellatus + (7), Desmostachya bipinnata + (8), Fagonia arabica + (12), Fagonia longispina + (11), Farsetia aegyptiaca + (12), Helianthemum lipii + (10), Indigofera articulata + (14), Lavandula coronopifolia + (14), Nerium oleander + (13), Phragmites australis + (13), Solanum nigrum + (1), Scirpus holoschoenus + (6), Solenostemma oleifolium + (14), Tamarix gallica + (11), Tephrosia leptostachya + (9), Ziziphus mauritianus + (10). 73
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ecologia mediterranea Vol. 38 (2) -
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ecologia mediterranea Revue interna
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Pr Thierry DUTOIT Éditeur en chef
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SÉLIMA BERCHI, AMEL AOUATI, KAMEL
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Page 19 and 20: CHIRAZ CHAFFEI HAOUARI, AFEF HAJJAJ
Page 25 and 26: CATERINA MAGRINI, MICHELE CENTO, EM
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Page 29 and 30: Les communautés bryophytiques du l
Page 31 and 32: Du point de vue de la structure du
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Page 35 and 36: Leptodictyo riparii-Fissidentetum c
Page 37 and 38: ait être assimilé en l’état à
Page 39 and 40: lent sur ces placages limoneux. Ain
Page 41 and 42: Meyran O., 1914. Catalogue des mous
Page 43 and 44: T. S. KSIKSI, N. O. ALSHAYGI 44 200
Page 45 and 46: T. S. KSIKSI, N. O. ALSHAYGI 46 Pig
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Page 51 and 52: Existing areas and past changes of
Page 53 and 54: Material and methods Area studied T
Page 55 and 56: zier 2004) wetland inventories. The
Page 57 and 58: Results Surface and number of exist
Page 59 and 60: Discussion Mediterranean wetlands:
Page 61 and 62: treated differently in each country
Page 63 and 64: DGF (Direction générale des forê
Page 65 and 66: Plant communities in the Tamanrasse
Page 67 and 68: elong to two major geomorphological
Page 69: The Rhus tripartita and Olea europa
Page 73 and 74: from sandy-silty, sandy to sandy-gr
Page 75 and 76: complex ecological situation and th
Page 77 and 78: Tamarix aphylla (Rudich & Danin 197
Page 79 and 80: Towards the establishment of a natu
Page 81 and 82: Introduction The structural complex
Page 83 and 84: Methods Species richness The field
Page 85 and 86: kurnet-es-sauda Eig.; Allium chlora
Page 87 and 88: tidissima, and J. excelsa) and the
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Page 91 and 92: Myers N., Mittermeier R.A., Mitterm
Page 93 and 94: Micromeria graeca (L.) Benth. Micro
Page 95 and 96: enlargement of this bioclimatic env
Page 97 and 98: à grande échelle au sein du proje
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