the Okavango Delta, and the Nata River, which originates in western Zimbabwe to flow into the eastern end of the Makgadikgadi Pan. Ecology Despite its aridity, the Kalahari Basin supports a variety of fauna and flora on soils known as Kalahari sands. The native flora includes acacia trees, African Rosewood and a large number of herbs and grasses. Some of the areas within the Kalahari are seasonal wetlands, such as the Makgadikgadi Pans of Botswana. This area, for example, supports numerous halophilic species and, in the rainy season tens of thousands of flamingos visit these pans. Water resource management The source of the Okavango Delta's waters in Angola and Namibia remain unaffected by any upstream dams or significant water abstraction and the three riparian states have established a protocol under the Permanent Okavango River Basin Water Commission (OKACOM) for the sustainable management of the entire river system. See also Nxai Pan Nata River Tsodilo Hills Lake Makgadikgadi - the paleo lake , the largest in Africa, which once occupied the basin until 10 thousand years ago. References C. Michael Hogan (2008) Makgadikgadi, Megalithic Portal, ed. A.Burnham Martin Leipold (2008) Plants of the Kalahari A.J.E. Els and K.M. Rowntree "Water Resources in the Savanna Regions of Botswana" Thieme, Michelle L. (2005). Freshwater Ecoregions of Africa and Madagascar: A Conservation Assessment. Island Press, Washington DC. Line notes Depressions (geology) Kalahari Desert