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Fig. 29. Bushy vegetation characteristic of the Great Erg; on the right, Ephedra
alata spp. alenda (gymnosperm); on the left, Calligonum sp. (Polygonaceae). Note
the wind-blown detritus around the base of the bushes.
and of the Saoura valley integrate in the same relationship. The following
individual relationships can be distinguished.
1. A hyperhalophilic association of Halocnemum strobilaceum localized the dried sebkhas in the summer
2. Two hyperhalophilic associations (the association of Arthocnemum indicum and the association of Salicornia arabica-Phragmites
communis) linked to consistently damp soils
3. Two halogypsophilic associations (the association of Salsola
sieben var. zygophylla-Zygophyllum cornutum and the association
Zygophyllum geslini-Tragnum nudatwn)
4. The association Suaeda vermiculata-Salsola foetida linked to
sand with lime and gypsum
On the other hand, the halophilic and halogypsophilic groups of the
oceanic and occidental Sahara are not very well known. We note, however,
the presence of a group of Limoniastrum ifniense and Nitraria retusa in
the beds of the wadis.
The halophilic vegetation of the littoral oceanic and of the sebkhas of