Ecologia Mediterranea

complex ecological situation and the limited
number of studies on those wadis. However,
we think it is possible to relate them to the
Pergulario-Pulicarietea (Quézel 1965) due to
the presence of several characteristic species
of the Acacia-Panicum desertic savannah. The
sandy nature of these wadis makes it impossible
to relate them to the Acacieto-Panicion
Quézel 1954. We thus propose a new alliance
to be defined in future field investigation in
order to describe this complex ecological situation.
The Tamarix gallica and
Desmostachya bipinnata community
This association corresponds to the floristic
group E3 identified by the correspondence
Table 6 – The Tamarix gallica-Desmostachya bipinnata association.
ecologia mediterranea – Vol. 38 (2) – 2012
Plant communities in the Tamanrasset region, Ahaggar, Algeria
analysis (Figure 4). It is represented by fourteen
relevés taken from wadi beds and nearby
terraces on sandy soils. The sampling was
done in wadi Tin Amzi south of Tamanrasset,
at altitudes between 950 and 1280 m (Figure
3). This plant unit is a shrub community
evolving on sandy grounds, with the water
table close to the surface, and is physiognomically
dominated by Tamarix gallica
(Table 6). It relates to the Tamarix gallica-
Desmostachya bipinnata association
described by Quézel (1965). The association
described in this study is impoverished, due
to the particularly dry period during the year
of sampling as well as showing a more disturbed
aspect as expressed through the abundance
of Calotropis procera, which has a frequency
of IV, and is well known to increase
in wadis where grazing pressure is high.
Quadrat number 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Altitude (m) 1150 1040 960 960 960 970 1150 1285 1120 1040 1010 1025 1680 950
Cover (%) 40 40 35 35 20 20 25 30 30 20 25 25 60 40
Number of Taxa 13 9 4 5 3 7 11 10 13 12 13 3 11 5
Caracteristics of the association CP
Tamarix gallica 3 3 3 3 2 2 2 2 2 2 2 2 + . V
Calotropis procera . . + 1 + 1 1 + + + 1 . . 2 IV
Desmostachya bipinnata . + . . . . + . . . . + . . II
Caracteristics of the Pergularieto-Pulicarietea Quézel 1965
Acacia tortilis subsp. raddiana 1 + 2 + . + + + + . . . + + IV
Panicum turgidum . . . . . . . . + + . 1 . . II
Acacia scorpioides . . . . . + . . . . . . . 3 II
Acacia ehrenbergiana . + . . . + . . . . . . . II
Cassia italica + . . . . . . + . . . . . . I
Pergularia tomentosa . . . . . . . + . . . . . . I
Ziziphus lotus
Psammophils
. . . . . . . . . . . . + . I
Artemisia campestris 2 . . . . . 1 + 2 . . . + . III
Cleome arabica + . . . . . + . . + + . . . III
Salvadora persica . . 1 + . + . . . . . . . + III
Atriplex halimus . 2 . . . . . . + . . . 2 . II
Artemisia judaica + . . . . . + . + . . . . . II
Tamarix aphylla . . . . . + . . + . + . . . II
Colocynthis vulgaris + . . . . . . . . . + . + . II
Salsola baryosma . + . . . . . . . 1 . . . . II
Cistanche phelypaea . + . . . . . . . + . . . . II
Euphorbia granulata + . . . . . . . . . + . . . II
Cynodon dactylon
Chasmophils
+ . . . . . + . . . . . . . II
Pulicaria crispa + . . + . . + + 1 + + . 1 . III
Zilla spinosa + . . . . . + 1 + + + . 2 . III
Pulicaria undulata + . . . + . + + + + + . . . III
Fagonia bruguieri . + . . . . . . + + 1 . + + III
Pituranthos scoparius + . . . . . . + . . . . 1 . II
Morettia canescens . . . . . . . . + . + . . . II
Atractylis aristata . . . . . . . . . + + . . . II
Moricandia arvensis . . . . . . . . . + + . . . II
Anabasis articulata . + . . . . . . . . . . + . II
Additional species: Aerva persica + (7), Boerhavia repens + (1), Helianthemum lippii + (13), Heliotropium bacciferum + (9), Olea europaea subsp.
laperrinei + (13), Paronychia capitata + (11), Scirpus holoschoenus + (1), Salvia chudaei + (13).
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