Of dunes, depressions and dry valleys: The arid landscapes of the Kalahari Desert

The combination of vegetated orange–red dunes , seasonal pans and dry valleys in the Kalahari creates a landscape with outstanding scientific and aesthetic value. This chapter describes the geomorphological features of the Kalahari Desert within South Africa and adjacent areas of Botswana and Namibia, with a special emphasis on aspects that make the landscape unique. The Kalahari is an arid to semi-arid region underlain by Cretaceous to recent Kalahari Group sediments , including a surface blanket of unconsolidated Kalahari sands . The landscape is dominated by three sets of landforms: (a) dry valley systems, including the Auob , Nossob , Kuruman and Molopo river s; (b) partially vegetated linear dunes , which stretch in a broad zone from Upington on the Orange River into Botswana and Namibia; and (c) seasonally flooded pan s. The importance of the long-term geological history of the Kalahari for understanding the present landscape is also discussed.