Abstract
Lebanon has witnessed an extensive urban development that resulted in the unmanaged exploitation of quarries which in turn has led to the degradation of natural ecosystems. This work attempts to characterize the vegetation and its dynamics on these degraded ecosystems. The phyto ecological results show that the composition of plant communities depends on the regional (rainfall/ vegetation level) as well as local (location, topographic situation, substrate) factors. On embankements, ecological processes reveal tolerance model followed by facilitation processes, whereas on cliffs the rapid turn over of speices might be the consequences of stresfull conditions on site. On platforms, the succession is very slow an probably follows facilitation model. This approach distinguishes different categories of species (major, rare, generalistic and indicator). these groupes represent an important basis for the choice of suitable species for restoration. The restoration streategy on quarry faces (cliffs) should be carefully planned as those sites respresent interresting habitats for endemic and rare species. Restoring platforms require heavy engineering investments for substrate modification. Restoring quarry embankements consists on short cutting the first stages dominated by annuals in order to promote a lasting vegetation cover by adding perrenial herbaceous or chamaephytes that will ensure lasting protection against soil erosion. Plants such as Salvia triloba, Ptilostemon chamaepeuce, Putoria calabrica, Stachys distans, Phagnalon rupestre, ou Hypparhenia hirta appear to be particularily suited for this task