Lake Rukwa is an
endorheic
An endorheic basin (; also spelled endoreic basin or endorreic basin) is a drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but drainage converges instead into lakes ...
lake located the
Rukwa Valley
The Rukwa Valley is a valley located in Rukwa Region, Songwe Region and Katavi Region in southwestern Tanzania. The valley is a part of the Great Rift Valley. Sparsely populated because of its harsh environment, its grassland biodiversity includ ...
of
Rukwa Region
Rukwa Region (''Mkoa wa Rukwa'' in Swahili) is one of Tanzania's 31 administrative regions with a postcode number 55000. The regional capital is the municipality of Sumbawanga. According to the 2012 national census, the region had a population ...
,
Songwe Region
Songwe Region (''Mkoa wa Songwe'' in Swahili) is a region of Tanzania created on 29 January 2016 from the western half of Mbeya Region. Its capital is Vwawa.
Geography
Songwe Region borders the countries of Zambia and Malawi to the south: Tund ...
and
Katavi Region
Katavi Region (''Mkoa wa Katavi'' in Swahili) is one of Tanzania's 31 administrative regions. The region covers an area of . The region is comparable in size to the combined land area of the nation state of Estonia. Kagera Region is bordered to ...
in southwestern
Tanzania
Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands and ...
. The lake is the third largest inland body of water in the country.
Geography
The alkaline Lake Rukwa lies midway between
Lake Tanganyika
Lake Tanganyika () is an African Great Lake. It is the second-oldest freshwater lake in the world, the second-largest by volume, and the second-deepest, in all cases after Lake Baikal in Siberia. It is the world's longest freshwater lake. ...
and
Lake Malawi
Lake Malawi, also known as Lake Nyasa in Tanzania and Lago Niassa in Mozambique, is an African Great Lake and the southernmost lake in the East African Rift system, located between Malawi, Mozambique and Tanzania.
It is the fifth largest fre ...
at an elevation of about , in a parallel branch of the rift system. Almost half of the lake lies in
Uwanda Game Reserve
Uwanda Game Reserve, also known as Uwanda Rukwa Game Reserve, is a reserve of the Rukwa Valley of southwestern Tanzania. It is an extension of Katavi National Park and covers an area of 4100 square kilometres. It includes almost half of Lake Rukwa ...
.
Hydrology
The lake has seen large fluctuations in its size over the years, due to varying inflow of streams. Currently it is about long and averages about wide, making it about in size. In 1929 it was only about long, but in 1939 it was about long and wide.
[Encyclopædia Britannica Online/Lake Rukwa](_blank)
/ref> 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. 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. (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.
Helium discovery
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.
See also
*Rift Valley lakes
The Rift Valley lakes are a series of lakes in the East African Rift valley that runs through eastern Africa from Ethiopia in the north to Malawi in the south, and includes the African Great Lakes in the south. These include some of the world's ...
References
Lakes of Tanzania
Saline lakes of the Great Rift Valley
Geography of Katavi Region
Geography of Rukwa Region
Geography of Songwe Region
Freshwater ecoregions of Africa
Important Bird Areas of Tanzania
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