THE BIOGEOGRAPHICAL AFFINITIES OF THE SEAWEED FLORA OF NATAL, SOUTH-AFRICA, AS TYPIFIED BY ISIPINGO BEACH - A MULTIVARIATE APPROACH

Isipingo Beach is one of the few South African east coast localities w ith a history of biogeographical study and is located centrally along the Natal coast. It was considered as representative of the 'sub-tropi cal east coast' by Stephenson and his co-workers in the 1930's and 194 0's. No biogeographical studies have been undertaken on the South Afri can east coast since. This paper describes a preliminary investigation of the floristic affinities of the seaweed flora of Natal (as represe nted by Isipingo Beach) and the rest of southern Africa.Correspondence and classification analyses indicate that whilst the Isipingo flora i s intermediate between the Natal north and south coasts, it has a clos er affinity to the flora of the Natal north coast and tropical areas t o the north. Species distribution patterns are discussed in relation t o recent work on the south and west coasts of South Africa and Inhaca Island, Mozambique. The biogeographical affinities of the Isipingo flo ra with the more distant warm temperate and tropical phytogeographic r egions of the world are also analyzed using multivariate techniques an d briefly discussed in relation to recent work on the southern African biogeographical regions.