Les ripisylves du nord de l’Algérie : essai de synthèse synsystématique à l’échelle de la Méditerranée occidentale

Abstract

The riparian forests in north Algeria : attempting to draw up a synsystematic synthesis in the western Mediterranean area. In Northern Africa, in recent decades, damage due to population increase, urbanisation and river management has resulted in a sharp decline in both area and quality of the forests in general, and riparian forests in particular. A regional study of the North Algerian riparian forests has been undertaken. Numerical analysis of the data revealed 3 main types of riparian forest communities, the plain alders of eastern Algeria, a biome unique to North Africa, riveraine forests of white poplar, the most important in their distribution and amount of surface cover, and high-altitude riparian forests, of which several new types have been described. This contribution aims mainly at comparing riparian forests from North Africa, which up till now had been poorly known and were not taken into account in a global system, with their homologue in the north-western Mediterranean sector. It submits a synsystematic diagram that does not only offer a new approach for all theses formations at the scale of the Western Mediterranean, but also shows the uniqueness of the riparian communities in the Maghreb (Clematido cirrhosae-Populion albae all. nov.) compared to the northerly Populion albae Br.-Bl. 1931.