A river delta in the Kalahari Desert – Okavango, Botswana |
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The Okavango Delta is a large low gradient alluvial fan or ‘Inland Delta’ located in north-western Botswana. The area includes permanent swamps which cover approximately 600,000 ha along with up to 1.2m ha of seasonally flooded grassland. The inscribed World Heritage property encompasses an area of 2,023,590 ha with a buffer zone of 2,286,630 ha. The Okavango Delta is one of a very few large inland delta systems without an outlet to the sea, known as an endorheic delta, its waters drain instead into the desert sands of the Kalahari Basin. It is Africa’s third largest alluvial fan and the continent’s largest endorheic delta. Furthermore it is in a near pristine state being a largely untransformed wetland system. The biota has uniquely adapted their growth and reproductive behaviour, particularly the flooded grassland biota, to be timed with the arrival of floodwater in the dry, winter season of Botswana.
Permanent crystal clear waters and dissolved nutrients transform the otherwise dry Kalahari Desert habitat into a scenic landscape of exceptional and rare beauty, and sustain an ecosystem of remarkable habitat and species diversity, thereby maintaining its ecological resilience and amazing natural phenomena. The annual flood-tide, which pulses through the wetland system every year, revitalizes ecosystems and is a critical life-force during the peak of the Botswana’s dry season (June/July). The Okavango Delta World Heritage property displays an extraordinary juxtaposition of a vibrant wetland in an arid landscape and the miraculous transformation of huge sandy, dry and brown depressions by winter season floods triggers spectacular wildlife displays: large herds of African Elephant, Buffalo, Red Lechwe, Zebra and other large animals splashing, playing, and drinking the clear waters of the Okavango having survived the dry autumn season or their weeks’ long migration across the Kalahari Desert. (Source: UNESCO WHC) Freshwater Ecoregion of the World : #569 Okavango Major Habitat Type: tropical and subtropical floodplain rivers and wetlands complexes |
Produced in 2014, including some images from 1988. Red dots indicate personal favorites. | |||
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