Lake Rukwa

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Lake Rukwa
Lake Rukwa.png
Lake Rukwa, as seen from space.
Lake Rukwa Basin OSM.png
Locationsouthwestern Tanzania
Coordinates8°00′S 32°25′E / 8.000°S 32.417°E / -8.000; 32.417Coordinates: 8°00′S 32°25′E / 8.000°S 32.417°E / -8.000; 32.417
Typealkaline
Catchment area88,000 km2 (34,000 sq mi)[1]
Basin countriesTanzania
Surface elevation800 metres (2,600 ft)

Lake Rukwa is an endorheic lake in the Rukwa Valley of southwestern Tanzania.

Geography[edit]

The alkaline Lake Rukwa lies midway between Lake Tanganyika and Lake Malawi at an elevation of about 800 metres (2,600 ft), in a parallel branch of the rift system. Almost half of the lake lies in Uwanda Game Reserve.[2]

Hydrology[edit]

The lake has seen large fluctuations in its size over the years, due to varying inflow of streams. Currently it is about 180 kilometres (110 mi) long and averages about 32 kilometres (20 mi) wide, making it about 5,760 square kilometres (2,220 sq mi) in size.[3] In 1929 it was only about 48 kilometres (30 mi) long, but in 1939 it was about 128 kilometres (80 mi) long and 40 kilometres (25 mi) wide.[4] During the early rifting of this part of Africa, the basin of Lake Rukwa may at times have been part of a much larger basin which also included the basins of Lake Tanganyika with Lake Malawi; ancient shorelines suggest a final date of overflow into Lake Tanganyika of 33,000BP.[5] For overflow to occur again, the lake's elevation would need to exceed 900 meters. Overflow into Lake Malawi is not possible now, since the pass between the two basin stands at over 2000 meters elevation.[6] (Neither Lake Tanganyika nor Lake Malawi can overflow into Lake Rukwa since they already overflow into the Atlantic and Indian Oceans respectively.)

There is an accumulation of selected heavy metals of Zinc, Mercury, Copper, Lead, Chromium and Nickel in sediment, water and muscle tissues of Clarias gariepinus (African catfish) and Oreochromis esculentus (Singida tilapia) fish was done in Lake Rukwa.[7]

Helium discovery[edit]

In 2016, an estimated 1.53 billion cubic meters (54.2 billion standard cubic feet) volume of helium gas was discovered in Lake Rukwa worth $3.5 billion.[8]

See also[edit]

References[edit]

  1. ^ Lake Rukwa Bathymetry Survey Final Report 2014
  2. ^ "Rukwa Uwanda Game Reserve". Utalii Travel and Safari. Retrieved 29 October 2010.
  3. ^ Google Earth accessed 6 February 2007
  4. ^ Encyclopædia Britannica Online/Lake Rukwa
  5. ^ Lévêque, Christian (1997). Biodiversity Dynamics and Conservation: The Freshwater Fish of Tropical Africa. Cambridge University Press. p. 110.
  6. ^ Google Maps
  7. ^ Mapenzi, Levinus Leonard; Shimba, Moses Joel; Moto, Edward Angelo; Maghembe, Reuben Silas; Mmochi, Aviti John (January 2020). "Heavy metals bio-accumulation in tilapia and catfish species in Lake Rukwa ecosystem Tanzania". Journal of Geochemical Exploration. 208: 106413. doi:10.1016/j.gexplo.2019.106413. ISSN 0375-6742.
  8. ^ "Helium 'could earn Tanzania $3.5bn'". www.thecitizen.co.tz. July 8, 2016.