Ecologia Mediterranea

from sandy-silty, sandy to sandy-gravelly substrates.
Altitude ranges between 800 and
1200 m. The plant community which occupies
this ecological niche belongs to the Acacia-Panicum
desertic savannah where the
dominant species are Acacia tortilis subsp.
raddiana and Leptadenia pyrotechnica
(Forssk.) Decne. with two facies: Chrozophora
brocchiana (Vis.) Schweinf. and Balanites
aegyptiaca (L.) Delile (Table 4).
From the floristic composition, it is quite
straightforward to relate the identified association
to the Pergulario-Pulicarietea Quézel
1965 and the Acacio-Panicion alliance. With
regard to the association itself, it compares to
the Leptadenia pyrotechnica-Chrozophora
brocchiana association described by Quézel
(1965). Analysis of Table 4 highlights a Bal-
Table 4 – The Leptadenia pyrotechnica-Chrozophora brocchiana association.
ecologia mediterranea – Vol. 38 (2) – 2012
Plant communities in the Tamanrasset region, Ahaggar, Algeria
anites aegyptiaca facies recorded in the
Timghrahine, Emedender and Tabanessift
wadis south-west of Tamanrasset (Figure 3)
and not observed by Quézel (1965). This
species replaces Chrozophora brocchiana
when the water table is deeper and soil texture
becomes sandier. Quézel (1965) provides
relevés from the Tibesti and Borkou regions
only, while our relevés have been taken south
of Tamanrasset. This confirms the northern
geographical extension of the association in
the Ahaggar. With regard to the naming of this
association, and because of the high frequency
of Acacia tortilis subsp. raddiana, we
propose to rename it as Acacia tortilis subsp.
raddiana-Leptadenia pyrotechnica association.
It illustrates far better the physiognomy
of this association in the field.
Quadrat number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Area (m²) 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200
Total cover (%) 20 15 20 20 15 15 35 15 40 30 20 30 35 35 35 30 25 25 15
Altitude (m) 950 950 950 980 890 900 1080 910 930 1144 1140 1000 830 900 920 1000 1230 1150 920
Number of Taxa 10 8 10 11 7 13 11 7 8 7 7 8 9 11 7 8 13 10 13
Caracteristics of the association
Acacia tortilis
CP
subsp. raddiana 2 2 + + + + + 1 2 + + + 3 + 2 1 + + + V
Leptadenia pyrotechnica + + + + + 1 1 1 2 + 1 1 + + 2 + + 1 + V
Chrozophora brocchiana 2 2 1 1 + + + + . . . . . . . . . . . III
Balanites aegyptiaca . . . . . . . . 3 3 2 2 1 3 3 2 2 2 2 IV
Caracteristics of the Acacio-Panicion Quézel 1965
Panicum turgidum + + . + 2 + + + . + + . + + . 1 + + + V
Zilla spinosa . . + 1 + . 2 . + + + + + + + + 1 + + V
Acacia ehrenbergiana + + + + 2 + 3 + . . . . + + . . + . 1 IV
Ziziphus lotus
Senna italica
. . + . + 1 + + . . + + . 1 . + . + IV
(Cassia aschrek) . + . . + . . + . . + . . . . + + + III
Maerua crassifolia . . + . . . . . . . . + + . . . . . II
Faidherbia albida . . . . . + . . . . . . . . . . . . I
Caracteristics of the Pergulario-Pulicarietea Quézel 1965
Pulicaria crispa + + + + . + . . + . . . 2 2 + . + + + IV
Pergularia tomentosa + + . . . + . . . + . . . + . + + . + III
Morettia canescens . . + + . . . . . . + . + . . . . . . II
Pulicaria undulata . 1 . . . . . . . . . + . . . + . . I
Trichodesma africanum . . . . + . . . . . . . . . . . . I
Heliotropium bacciferum . . . . . . . . . . . . . . . . . + I
Transgressives of the Asterisceto-Forsskaoletea Quézel 1965
Aerva javanica 1 1 + . . 1 + + + . + + + + + + + + + V
Fagonia bruguieri
Psammophils
. . . + . . + . . + . . . + . . . . . III
Artemisia campestris . . . . . . . . . . . + . . . . . + . I
Calotropis procera 1 1 . . . . . . . . . . . . . + . . . I
Paronychia arabica . . . . . . . . . . . . . . . . . . + I
Matthiola livida . . . . . . . . . . . . . . . . + . . I
Artemisia judaica . . . . + + . . . . . . . . . . . . . I
Stipagrostis pungens
Chasmophils
+ + . . . . . . . . . . . . . . . . . I
Stipagrostis ciliata . . . . . . + . . . . . . . . . . . . I
Stipagrostis obtusa . . . . . + . . . . . . . . . . . . . I
Atractylis aristata . . . . . . . . . . . . . . . . . + . I
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