Ecologia Mediterranea
Ecologia Mediterranea
Ecologia Mediterranea
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N. BOUCHENEB, S.S. BENHOUHOU<br />
The Acacia tortilis subsp raddiana and<br />
Salvadora persica community<br />
This association corresponds to the floristic<br />
group E5 identified by the correspondence<br />
analysis (Figure 4). It is represented by nineteen<br />
relevés taken from large wadi beds and<br />
nearby terraces. The soil has a sandy compact<br />
to gravelly-sandy substrate and altitude ranges<br />
between 930 and 1200 m. The association<br />
was observed in wadi Tehart and in wadi<br />
Ti-n-Amzi (Figure 3). The plant community<br />
encountered in these wadis is part of the Acacia-Panicum<br />
desertic savannah where Salvadora<br />
persica L. is dominant (Table 3).<br />
A detailed analysis of the floristic content of<br />
the relevés makes it clear that this association<br />
is related to the Acacio-Panicion and the Pergulario-Pulicarietea<br />
Quézel 1965 (Table 3).<br />
However, this association does not compare<br />
to any of the associations described by former<br />
workers in the Ahaggar for the Acacia-Panicum<br />
desertic savannah. When comparing the<br />
Cassia aschrek-Panicum turgidum association<br />
with the Acacia tortilis subsp. raddiana-Salvadora<br />
persica community, they show differ-<br />
Table 3 – The Acacia tortilis subsp. raddiana-Salvadora persica association.<br />
74<br />
ent edaphic profile and consequently show a<br />
different species assemblage. The community<br />
described in those particular wadis is characterised<br />
by the original and unique assemblage<br />
of Acacia tortilis subsp. raddiana and Salvadora<br />
persica. The combination of altitudinal<br />
(between 930 and 1250 m), edaphic characteristics<br />
(sandy-gravelly substrate) and wadi<br />
geomorphology (large wadi beds) are the<br />
main physical and environmental factors contributing<br />
to the development of such a distinctive<br />
association. It is therefore proposed<br />
as a new association identified in the Ti-n-<br />
Amzi and Tehart wadis.<br />
The Leptadenia pyrotechnica and<br />
Chrozophora brocchiana community<br />
This association corresponds to the floristic<br />
group E6 identified by the correspondence<br />
analysis (Figure 4). It is represented by nineteen<br />
relevés taken from wadi beds, their tributaries<br />
and outwash zones of the Amaghalghal<br />
and Anefeg wadis, the In-Aha-Guieh<br />
wadi from the Touf Admer massif. Soil varies<br />
Quadrat number 1 2 3 4 5 6 7 8 9 10 11 12 13 14<br />
Area (m²) 200 200 200 200 200 200 200 200 200 200 200 200 200 200<br />
Total cover (%) 20 30 30 30 30 20 30 35 20 20 20 25 15 20<br />
Altitude (m) 980 980 980 930 950 1000 950 1000 1075 1090 1150 1200 1080 910<br />
Number of Taxa 8 6 13 8 9 8 9 8 6 7 9 12 6 9<br />
Caracteristics of the association CP<br />
Acacia tortilis subsp. raddiana 1 2 1 2 2 + 2 3 2 2 2 2 + + V<br />
Salvadora persica 2 2 2 1 1 1 1 1 1 1 1 + + . V<br />
Caracteristics of the Acacio-Panicion Quézel 1965<br />
Zilla spinosa + 1 3 . + . + 1 + 2 + 2 1 1 V<br />
Panicum turgidum + + + + + + + . + . . + + . IV<br />
Acacia ehrenbergiana + . + . + 2 + . . . + + . . III<br />
Senna italica (Cassia aschrek) . . . + . . . + + + . . . . III<br />
Balanites aegyptiaca . . . . . . . 1 . . . + + + III<br />
Maerua crassifolia . . + . . . . . . . + . . . II<br />
Ziziphus lotus . . . . . + . . . . . . . . I<br />
Caracteristics of the Pergulario-Pulicarietea Quézel 1965<br />
Pulicaria crispa . + 1 + . 1 + . . + + + + + IV<br />
Leptadenia pyrotechnica + . . . + + 1 2 . . + 1 . 2 IV<br />
Pergularia tomentosa . . . + . . . . . + + + . + III<br />
Morettia canescens . . + . . . . . + . . . . . II<br />
Heliotropium bacciferum<br />
Psammophils<br />
+ . . . . . . . . . . . . . I<br />
Calotropis procera . . + + + + + + . . + 1 . + IV<br />
Artemisia judaica . . + . . . . . . . . + . . II<br />
Tamarix aphylla . . . . . . . . . . . . . + I<br />
Farsetia ramosissima . . . . + . . . . . . . . . I<br />
Chrozophora brocchiana<br />
Chasmophils<br />
. . 1 . . . . . . . . . . . I<br />
Aerva javanica + + + + + . + + . . . + . + IV<br />
Farsetia aegyptiaca . . + . . . . . . . . . . . I<br />
Deverra scoparia subsp. scoparia . . . . . . . . . + . . . . I<br />
ecologia mediterranea – Vol. 38 (2) – 2012