Vikariierende Heidebuschwälder und ihre Kontaktgesellschaften in Makaronesien und Zentralafrika
Lösch, R.; Fischer, E.
Vicarious Ericaceous shrub communities on the Macaronesian islands and in continental Africa (Kahuzi-Biega-National Park) are described. On Mt. Kahuzi five plant communities from the Ericaceous belt can be distinguished. Several dominant species do occur in both areas (e.g. Erica arborea) or are represented by closely related taxa (e.g. Myrica faya/M. salicifolia, Hypericum canariense/H. revolutum and Vaccinium maderense/ V. stanley). The distribution of these vicarious taxa is discussed. Beside the disjunct Macaronesian elements some plants with South African distribution (Helichrysum, Disa) reach the Central African Ericaceous shrub communities. A third group to be mentioned is the lowland tropical element (e.g. Schefflera) containing several taxa that reach the montane forest belt and the afroalpine zone. A natural relationship and a joint origin of the Ericaceous vegetation in Macaronesia and Central Africa is assumed because of the floristic and ecological affinities. The South African elements probably did not reach the north-western margin of the African continent. The common species presumably had a larger and ± closed distribution in Northern Africa during late tertiary and they were repressed by climatic changes to relic montane areas.