Mount Kilimanjaro - Unique Vegetation

Unique Vegetation

Being an Afromontane sky island, Kilimanjaro has an enormous biodiversity while low in endemic species. However endemics include the giant groundsels in the bunchgrass tussock grasslands, and other flora adapted to living in alpine plant conditions.

Kilimanjaro has a large variety of forest types over an altitudinal range of 3,000 m (9,843 ft) containing over 1,200 vascular plant species. Montane Ocotea forests occur on the wet southern slope. Cassipourea and Juniperus forests grow on the dry northern slope. Subalpine Erica forests at 4,100 m (13,451 ft) represent the highest elevation cloud forests in Africa. In contrast to this enormous biodiversity, the degree of endemism is low. However, forest relicts in the deepest valleys of the cultivated lower areas suggest that a rich forest flora inhabited Mt Kilimanjaro in the past, with restricted-range species otherwise only known from the Eastern Arc mountains. The low degree of endemism on Kilimanjaro may result from destruction of lower elevation forest rather than the relatively young age of the mountain.

Another feature of the forests of Kilimanjaro is the absence of a bamboo zone, which occurs on all other tall mountains in East Africa with a similarly high rainfall. Sinarundinaria alpina stands are favoured by elephants and African Buffalos elsewhere. On Kilimanjaro these megaherbivores occur on the northern slopes, where it is too dry for a large bamboo zone to develop. They are excluded from the wet southern slope forests by topography and humans, who have cultivated the foothills for at least 2000  years.

This interplay of biotic and abiotic factors could explain not only the lack of a bamboo zone on Kilimanjaro but also offers possible explanations for the patterns of diversity and endemism. If true, Kilimanjaro's forests would serve as a striking example of the large and long-lasting influence of both animals and humans on the African landscape.