Rukwasee
| Rukwasee | |
|---|---|
|
|
| Rukwasee, seen from space | |
| Geographical location | Southwest Tanzania |
| Tributaries | Rungwa , Songwe , Muze, Momba, Luiche, Katuma |
| Drain | No drain |
| Location close to the shore | Rungwa , Sumbawanga |
| Data | |
| Coordinates | 8 ° 0 ′ S , 32 ° 21 ′ E |
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| Altitude above sea level | 800 m |
| surface | 5 760 km² |
| length | 180 km |
| width | 32 km |
| Maximum depth | 5 m |
| Middle deep | 3 m |
| Catchment area | 85,000 km² |
The Rukwasee (formerly also Rikwasee , English Lake Rukwa ) is an outflowless salt lake in southwestern Tanzania . The area around the lake is almost uninhabited, but many commuters come here to fish. The lake is partly in the area of the Uwanda Game Reserve .
Geography, extent and ecology
Located halfway between Lake Tanganyika and Lake Nyassa at an altitude of 800 meters above sea level, it is located in a depression that lies parallel to the Great Rift Valley . Over the years, the lake has seen major changes in size, caused by varying amounts of inflow from watercourses. It is currently about 180 kilometers long and an average of about 32 kilometers wide, which makes 5760 square kilometers. In 1939 the dimensions of the lake were 128 kilometers by 40 kilometers; In 1929, however, it was only 48 km long. Sometimes it is completely dried out. Since about 2007 its average water level has dropped from 9.5 to 3.4 meters. Important tributaries include the Rungwa River (from the north), the Lupa, Chambua and Songwe Rivers (from the south) and the Momba River (from the west).
Although the lake is fed by 17 constant and seasonal streams, its water volume decreases year by year. Built dams and the development of irrigation systems in the villages of its catchment area reduce the amount and duration of the water inflow and thereby impair the availability of water in the lake. Due to the increasing agricultural use of the bank zones along the rivers and the clearing of nearby forests, soil erosion occurs and thus considerable amounts of suspended matter in the form of silt and agricultural waste enter the lake via the rivers .
geology
Previously used sedimentary salt deposits on the lake are located in salt pans on its west coast. Around 1936, the Belgian geologist and mining engineer Jean de La Vallée Poussin found deposits of gold, lead and copper ores in the adjacent area to the west of the lake that stretch as far as Mpanda . Industrial mining began here in 1947 with Uruwira Minerals Ltd. Until today (2017) there has been artisanal gold mining in the neighboring mountains using the amalgam process , whereby mercury components get into the lake via the watercourses flowing in it.
history
For European research, the lake was discovered by John Hanning Speke , the next traditional European visitor was the Scottish explorer Joseph Thomson , who saw the Rukwasee from a short distance in 1880.
nature
The Lake Rukwa in the Uwanda game park embedded, live in the shallow waters crocodiles, hippos and 59 different species of fish, including the Tigersalmler ( Hydrocynus vittatus ), two Brycinus species, the cichlids redbreast tilapia , Pseudocrenilabrus philander and tilapia sparrmanii , three Oreochromis - Species, the catfish Auchenoglanis occidentalis , Heterobranchus longifilis and Schilbe mystus , five whiskered catfish ( Synodontis ), three catfish species of the genus Chiloglanis , eight barbel from the genus Enteromius , the pikeperch ( Polypterus ornatipinnis ), and the East African lungfish ( Protonus amphibius ).
literature
- Lothar Seegers: The fishes of the Lake Rukwa drainage . Annals. Zoological wetenschappen = Annales. Sciences zoologiques. Vol. 278. Koninklijk Museum voor Midden-Afrika , Tervuren 1996. ISBN 9075894031
swell
- ↑ a b Ashley Brown, Robin Abell, Tim Davenport: Lake Rukwa . at www.feow.org (English).
- ↑ a b c Subhojit Goswami: As Tanzania's Lake Rukwa continues to dry up, NGOs focus on sensitizing locals . Posted on June 14, 2017 at www.downtoearth.org.in (English).
- ↑ Google Earth, February 6, 2007
- ↑ Britannica.com: Lake Rukwa ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. .
- ^ René A. Pelletier: Mineral Resources of South-Central Africa . Oxford University Press , Cape Town / London / New York / Toronto 1964, pp. 255, 258.
- ↑ Lake Rukwa | lake, Tanzania. Encyclopaedia Britannica, accessed February 28, 2020 .
- ^ Joseph Thomson - Encyclopedia. Retrieved February 28, 2020 .
- ↑ Quantitative Aquatics, Inc. (Webmaster): Species in Lake Rukwa . at www.fishbase.se (English and other languages).
- ↑ JISC: bibliographic evidence .
