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The Makgadikgadi Pan (Tswana pronunciation (:maqʰadiˈqʰaːdi)), a salt pan situated in the middle of the dry savanna of north-eastern Botswana, is one of the largest salt flats in the world. The pan is all that remains of the formerly enormous Lake Makgadikgadi, which once covered an area larger than Switzerland, but dried up several thousand years ago. ==Location and description== Lying southeast of the Okavango Delta and surrounded by the Kalahari Desert, Makgadikgadi is technically not a single pan but many pans with sandy desert in between, the largest being the Sua (Sowa), Nwetwe and Nxai Pans. The largest individual pan is about . In comparison, Salar de Uyuni in Bolivia is a single salt flat of , rarely has much water, and is generally claimed to be the world's largest salt pan. A dry salty clay crust most of the year, the pans are seasonally covered with water and grass, and are then a refuge for birds and animals in this very arid part of the world. The climate is hot and dry but with regular annual rains. The main water source is the Nata River, called Amanzanyama in Zimbabwe, where it rises at Sandown about from Bulawayo. A smaller amount of water is supplied by the Boteti River from the Okavango delta. These salt pans cover in the Kalahari Basin and form the bed of the ancient Lake Makgadikgadi, which evaporated many millennia ago. Archaeological recovery in the Makgadikgadi has revealed the presence of prehistoric man through abundant finds of stone tools; some of these tools have been dated sufficiently early to establish their origin as earlier than the era of ''Homo sapiens''.〔C. Michael Hogan (2008) ''Makgadikgadi'', The Megalithic Portal, ed. A. Burnham ()〕 Pastoralists herded grazing livestock here when water was more plentiful earlier in the Holocene.〔Chris McIntyre (2008) ''Botswana: Okavango Delta, Chobe, Northern Kalahari'', Bradt publishers, 502 pages ISBN 1-84162-166-8〕 The lowest place in the basin is Sua Pan with an elevation of 2,920 feet.〔Helgren, David M. (1984) "Historical Geomorphology and Geoarchaeology in the Southwestern Makgadikgadi Basin, Botswana" ''Annals of the Association of American Geographers'' 74(2): pp. 298-307, page 299〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Makgadikgadi Pan」の詳細全文を読む スポンサード リンク
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