In a fuller account of the regions to be published elsewhere I refer briefly to 

 the major features of vegetation, productivity actual and potential, and the nature of 

 the threat already evident as the outcome of man's action. 



(1) The Namib and the Great Nama Land Deserts 



(i) The Namib 

 (ii) The Great Nama Land Desert. 



(2) The Sub- Deserts of the Karroo and the Kalahari 



(i) The Karroo 

 (ii) The Sub- Desert Kalahari. 



(3) Certain Dry Tropical /Sub- Tropical Regions of Southern and Eastern Africa 



(i) Arid Regions 



(a) Arid portions of the North- Central Cape Province, South- Western and 

 Western Orange Free State and Extreme Western Transvaal. 



(b) The Arid Kalahari 



(c) The Arid Limpopo Region 



(d) Arid Portions of North- Eastern Tanganyika and South East Kenya to- 

 gether with Arid country linking with the 'Somali' Region to the North 



(e) The Arid 'Somali' Region, 

 (ii) Sub- Arid Regions 



(a) The sub- arid Bushveld of the Transvaal 



(b) Sub- arid regions in Northern Bechuanaland and Sotithern Rhodesia 



(c) Sub- arid portions of Central Tanganyika 



(i) Tribal Agriculture 



(ii) East African Groundnuts Scheme: Kongwa Region, 

 (iii) Semi- Sub- Arid Regions. 



IV Some Ecological Phenomena and Problems. 



In the fuller record to be published elsewhere I deal briefly with the following 

 ecological phenomena and problems:- 



(1) Habitat Factors 



(i) Radiation 

 (ii) Humidity 

 (iii) Evaporation 

 (iv) Dew 

 (v) Rainfall 

 (vi) Edaphic factors. 



(2) Biological and Ecological Phenomena 



(i) Succession and development 



(ii) Community and climax 



(iii) Physiological and aut- ecological investigations 

 (iv) Physiology and reactions of animals 



(v) The role of fire. 



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