Cumulative DatasetThe Southern Africa tree dataset covers 354 1-degree grid cells out of the total 2169 of sub-Saharan Africa. 1353 taxa are mapped, creating a total cover of 35265 records.
Tree Species Diversity is centred in the Natal Province of South Africa on the Mozambique/South Africa/Swaziland border. It appears to radiates southwards from here towards the Cape Province, and northwards through the Transvaal into eastern Zimbabwe. This pattern is shared by Endemism, except it is centred in east Zimbabwe.
The top 2 major hotspots are in Natal, with 5 of the remaining 8 hotspots clustered in the same locality. The remaining 3 hotspots are situated in eastern Zimbabwe on the Zimbabwe/Mozambique border.
The source of the Southern Africa Tree distribution data is:
Palgrave, K. C. (1977) Trees of Southern Africa. C. Struik Publishers. Cape Town, South Africa.
Aside from the obvious ‘trees’ – large specimens with comparatively large boles, borderline trees have been included in the study according to the following criteria::
“The evidence of any reputable collector who has recorded a specimen as a ‘tree,’ even once.”
This works on the assumption that is is wiser to include a few non-tree species than omit valid ones.