Sudd
The Sudd , from the Arabic Sadd /سد / ‚Barrier; also: dam ', is a swamp and floodplain formed by the Nile in South Sudan , which is one of the largest swamp areas in the world.
location
It is approximately 390 km long in the north-south extension, 240 km in the east-west extension and covers an area of around 30,000 km², the size of which varies greatly and can be up to 130,000 km² in the rainy season. The marshland lies in the triangle of the cities of Bor , Wau and Bentiu . Along the Bahr al-Dschabal (Nil) the Sudd of boron extends to the no-see .
Bor is about 427 m above sea level. d. M., the Bentiu 390 km away as the crow flies 398 m above sea level. d. M. The gradient is therefore only around 0.07 m / km.
In this section, the Nile is not tied to a specific river bed, but spreads out into a large swamp area with various branches of the river. Depending on the water level and the amount of rain, large areas of grass are sometimes flooded, which means that the entire region is sometimes barely passable. The size of the floodplain fluctuates in the course of the year and from year to year and is closely linked to the flow rate from the equatorial lakes; it has fluctuated between 20,000 and 30,000 km² since 1964.
flora
The Sudd is considered the most fertile zone in the country. Papyrus , reeds , water hyacinths and many different marsh plants grow in the area . Even remnants of tropical rainforests with mahogany trees can be found around the Sudd.
Hydrology
The sudd is primarily influenced by the amount of water draining from Lake Victoria . The swamp grassland receives an annual average of 700 to 1000 mm of precipitation. One can speak of two seasons, from 4½ to 6½ wet, rainy months in summer, the rest of the year is relatively dry.
Since the water in the Sudd flows extremely slowly due to the very low gradient of the river and is distributed over a large area, 53.2 percent of the Nile water is lost through evapotranspiration , i.e. through direct evaporation and evaporation through plants. The Sudanese government in Khartoum therefore had plans to drain the water from the Sudd through the 300 km long Jonglei Canal and use it to irrigate agricultural areas. However, due to the civil war in the south of the country, construction work stopped in 1983. A possible continuation of the project is discussed controversially. The north of Sudan would benefit from the diversion, as more water would then be carried northwards. The Sudd would, however, dry out, but further agricultural areas in the north or in the Sudd area could be cultivated.
navigability
The Sudd was difficult to navigate for a long time, as the constantly changing arms of the river can hardly be surveyed and are often clogged by floating islands made of papyrus, reeds and water hyacinths. In the years 1899 to 1903, a shipping channel through the Sudd was cleared, which enabled regulated shipping. The fairway also increased the outflow from the Sudd into the White Nile by around 200 m³ / s, which was a welcome addition to the enormous water structures in progress at this time ( Aswan dam , Asyut dam etc.). However, the fairway had to be constantly maintained. The connection was interrupted by the civil war in South Sudan .
Settlement
As a result of the civil war in South Sudan from 2013 to 2018 , the population of (Old) Fangak , which is difficult to access in the Sudd, rose from 5,000 to approx. 50,000 during these war years due to refugees who were brought in.
literature
- Josef Nyáry , photos: Milan Horacek: Sudan: The Moloch from Sudd In: Geo-Magazin. Hamburg 1979.7, pp. 66-90. Informative experience report: "Sudan is experimenting with Africa's largest swamp area. A canal ( Jonglei Canal ) is supposed to take the water from it and feed it to the Nile. But the shepherds of the Shilluk , Dinka and Nuer have to pay for this giant channel , whose way of life has dramatically changed becomes." ISSN 0342-8311
- Current hydrological research programs on the Sudd
- Georg Petersen: The hydrology of the Sudd: hydrologic investigation and evaluation of water balances in the Sudd swamps of southern Sudan ( Die Hydrologie des Sudd: hydrological investigations and evaluation of the water balance in the Sudd swamps of South Sudan ). Dissertation, Kiel 2008. ( Metadata with link to the complete dissertation. PDF file; 5921 KB)
- William Willcocks, James Ireland Craig: Egyptian Irrigation Volume I ; Egyptian Irrigation Volume II. 3rd edition. Spon, London / New York 1913.
Web links
Individual evidence
- ↑ South Sudan. Federal Foreign Office, August 2017, accessed on 14 October 2017 .
- ↑ a b The Impenetrable Wetlands of Sudd in South Sudan. Amusing Planet, 2017, accessed October 14, 2017 .
- ↑ South Sudan. The country information portal, May 2017, accessed on October 14, 2017 .
- ^ Yannick von Eisenhart Rothe: South Sudan's internal refugees: Security in the swamp . In: Spiegel Online . July 24, 2019 ( spiegel.de [accessed July 24, 2019]).
Coordinates: 8 ° 0 ′ 0 ″ N , 31 ° 0 ′ 0 ″ E