Etosha pan

The Etosha pan is a large endorheic salt pan, forming part of the Kalahari Basin in the north of Namibia. The 120-kilometre-long (75-mile-long) dry lakebed and its surroundings are protected as Etosha National Park, one of Namibia's largest wildlife parks. The pan is mostly dry but after a heavy rain it will acquire a thin layer of water, which is heavily salted by the mineral deposits on the surface of the pan, which most of the year is dry mud coated with salt.

Contents

Location and description

The area exhibits a characteristic white and greenish surface, which spreads over hundreds of kilometres. The pan developed through tectonic plate activity over 10 million years. About 16,000 years ago, when ice sheets were melting across the Northern Hemisphere land masses, a wet climate phase in southern Africa filled Etosha Lake. Today the Etosha Pan is mostly dry clay mud split into hexagonal shapes as it dries and cracks and seldom seen with even a thin sheet of water covering it. It is assumed that today's Kunene River fed the lake at that time but over time plate movements caused a change in river direction causing the lake to run dry and leave a salt pan. Now the Ekuma River is the sole source of water. Typically, little river water or sediment reaches the dry lake because water seeps into the riverbed along its 250-kilometre (160 mi) course, reducing discharge along the way.

The surrounding area is dense mopane woodland which is occupied by herds of elephants on the south side of the lake. Mopane trees are common throughout south-central Africa, and host the mopane worm, which is the larval form of the moth Gonimbrasia belina and an important source of protein for rural communities. The area was first explored by the Europeans Charles John Andersson and Francis Galton in 1851. The American commercial traveller McKeirnan visited the area in 1876.

Flora

The salt desert supports very little plant life except for the blue-green algae that gives the Etosha its characteristic colouring and grasses like Sporobolus spicatus which quickly grow in the wet mud following a rain. Away from the lake there is grassland that supports grazing animals.

Fauna

This harsh dry land with little vegetation and salty water if any at all supports little wildlife all year round but is used by a large number of migratory birds. The hypersaline pan supports brine shrimp and a number of extremophile micro-organisms tolerant of the high saline conditions.(C.Michael Hogan. 2010.) In particularly rainy years the Etosha pan becomes a lake approximately 10 cm in depth and becomes a breeding ground for flamingos, which arrive in their thousands, and Great White Pelican (Pelecanus onocrotalus). The surrounding savanna is home to a number of mammals that will visit the pan and surrounding waterholes when there is water, these include quite large numbers of zebra (Equus burchelli), Blue Wildebeest (Connocheatus taurinus), and springbok (Antidorcas marsupialis) as well as white rhinoceros, elephants, hunting dogs, lions, leopards, and antelopes.

Threats and protection

The Etosha pan is completely within the national park and is designated as a Ramsar wetland of international importance and a World Wildlife Fund ecoregion (Etosha Pan halophytics).

Sundries

The Etosha area was used as a backdrop during the filming of "star wars the 4th'

References