作者: PETER GOLDBLATT
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摘要: Comprising a land area of ca 90000 km2, less than 4% the total for Southern African subcontinent, Cape Floristic Province is one world's richest areas in terms botanical diversity its size. An estimated 8650 species vascular plants occur this area, about 65% which are endemic. This 42% all southern Africa. The number packed into so small an remarkable temperate zone, and compares closely with totals comparable size wet tropics. Region consists mosaic sandstone shale substrates that give rise to soils quite different types, addition local limestone add edaphic diversity. Climates across region extremely variable, predominant orographic rainfall pattern ranges from 2000mm locally 100mm, often steep gradients, result mountainous landscape. resulting compounded by sharp gradients precipitation creates unusual habitats. A feature some low nutrient levels many on such have seed dispersal capabilities, factor important explaining high endemism. Species richness hypothesized resulted presence complex diverse habitats ecological against background relatively stable climate geology after mediterranean was established there sometime beginning Pliocene. or mode speciation may been more under these conditions allopatric speciation.