Lake Victoria is sixty eight,800 rectangular kilometres (26,560 mi²) in size, making it the continent's largest lake, the biggest tropical lake inside the world, and the second biggest fresh water lake in the international in phrases of floor place. Being noticeably shallow for its length, with a most depth of 84 m (276 feet) and a median intensity of 40 m (131 toes), Lake Victoria ranks because the 7th biggest freshwater lake by way of quantity, containing 2,750 cubic kilometres (2.2 million acre-toes) of water. It is the source of the longest branch of the Nile River, the White Nile, and has a catchment location of 184,000 rectangular kilometres (71,040 mi²). The lake lies within an accelerated plateau inside the western part of Africa's Great Rift Valley and is problem to territorial administration by means of Tanzania, Uganda and Kenya. The lake has a coastline of three,440 km (2138 miles), and has more than 3,000 islands, many of which can be inhabited. These encompass the Ssese Islands in Uganda, a massive group of islands inside the northwest of the Lake which might be becoming a famous destination for vacationers.
Geology
Lake Victoria is distinctly younger; its current basin fashioned only four hundred,000 years ago, whilst westward-flowing rivers have been dammed with the aid of an upthrown crustal block. The lake's vanity, constrained river inflow, and big floor area relative to its volume make it vulnerable to weather modifications; cores taken from its bottom display that Lake Victoria has dried up absolutely 3 times since it fashioned. These drying cycles are probably related to past ice ages, which might be times while precipitation declined globally. The lake last dried out 17,three hundred years in the past, and crammed once more starting 14,700 years ago; the exquisite adaptive radiation of its native cichlids has taken area within the short time period when you consider that then.
Exploration records
The first recorded information approximately Lake Victoria comes from Arab traders plying the inland routes on the lookout for gold, ivory, different precious commodities and slaves. An first-rate map called the Al Adrisi map dated from the 1160s, genuinely depicts an accurate representation of Lake Victoria, and attributes it as being the supply of the Nile.
The lake become first sighted by means of Europeans in 1858 when the British explorer John Hanning Speke reached its southern shore while on his journey with Richard Francis Burton to discover imperative Africa and find the super Lakes. Believing he had located the source of the Nile on seeing this tremendous expanse of open water for the primary time, Speke named the lake after the then Queen of the UK. Burton, who have been improving from infection at the time and resting further south at the shores of Lake Tanganyika, became outraged that Speke claimed to have proved his discovery to had been the actual source of the Nile whilst Burton appeared this as nevertheless unsettled. A very public quarrel ensued, which no longer handiest sparked a terrific deal of excessive debate in the clinical network of the day, however an awful lot interest with the aid of different explorers keen to either verify or refute Speke's discovery.
The widely known British explorer and missionary David Livingstone failed in his try to confirm Speke's discovery, rather pushing too far west and getting into the Congo River gadget instead. It was ultimately the American explorer Henry Morton Stanley who confirmed the reality of Speke's discovery, circumnavigating the Lake and reporting the brilliant outflow at Rippon Falls at the Lake's northern shore. It became on this adventure that Stanley become said to have greeted the British explorer with the well-known phrases Dr. Livingstone, I presume?, upon coming across the Scotsman sick and despondent in his camp at the beaches of Lake Tanganyika.
Ecology and social influences
Lake Victoria plays a vital position in helping the tens of millions of human beings residing round its beaches, in one of the maximum densely populated regions on this planet.
The surroundings of Lake Victoria and its environment had been badly affected by human influence. In 1954, the Nile perch ( Lates niloticus) turned into first delivered into the lake's ecosystem in an try to enhance fishery yields of inside the lake. Introduction efforts intensified in the course of the very early 1960's. The species was found in small numbers till the early to mid 1980's, whilst it underwent a large population expansion and came to dominate the fish community and ecology of the sector's biggest tropical lake. Also added become Nile tilapia (Oreochromis niloticus), now an vital food fish for neighborhood intake. The Nile perch proved ecologically and socioeconomically devastating. Together with pollution born of deforestation and overpopulation (of each human beings and domestic animals), the Nile perch has introduced approximately a huge transformation within the lake environment and to the disappearance of loads of endemic haplochromine cichlid species. Many of these are now presumed to be extinct.
Also vanished from Lake Victoria is one in all two local species of tilapia (another form of cichlid fish), known as the ngege, Oreochromis esculentus. The ngege is advanced in taste and texture to Nile tilapia, however it does now not develop as speedy or as huge and produces fewer young. Ngege and a few representatives of haplochromine diversity live to tell the tale in minute swamp ponds and lakes that dot the Lake Victoria Basin. The initial good returns on Nile perch catches, at their peak delivering export revenues of numerous hundred million greenbacks a 12 months, have diminished dramatically because of bad enforcement of fisheries policies. The proceeds from Nile perch income remain an vital monetary engine within the region, but the resulting wealth could be very poorly distributed and the overall stability sheet at the Nile perch introduction to Lake Victoria is well into the purple regardless of the massive price of the perch landings as an export commodity.
The 3 countries bordering Lake Victoria- Uganda, Kenya and Tanzania- have agreed in precept to the idea of a tax on Nile perch exports, proceeds to be carried out to diverse measures to gain nearby communities and maintain the fishery. However, this tax has not been put into pressure, enforcement of fisheries and environmental legal guidelines generally are lax, and the Nile perch fishery remains in essence a mining operation. Currently, the Nile perch is being overfished. Populations of a few endemic cichlid species have multiplied once more, specially or three species of zooplankton-ingesting, herring-like cichlids (Yssichromis) that faculty with an considerable native minnow recognized regionally as dagaa (Tanzania), omena (Kenya), or mukene (Uganda). In 1996 The World Bank funded a assignment to restore and preserve the ecology of Lake Victoria and its fisheries, known as LVEMP (Lake Victoria Environmental Management Project).
Meanwhile, the EU invested some other massive sum in fisheries infrastructure and monitoring. Few of the wonderful intentions of those tasks had been actualized despite massive fees, but the ability for matters to be set aright continues to be notable and through it all of the ecology of Lake Victoria, in its new incarnation, has established amazingly resilient. One useful product of those foreign useful resource programs has been the education of a brand new era of east African aquatic ecologists, conservation specialists, and fisheries scientists. There has also been a renaissance in the fishery studies institutes of the lake. Unfortunately, few of the new professionals locate jobs, and fewer still discover jobs that permit them to apply what they've discovered to fixing, in place of perpetuating, the deep problems that still beset the connection among human beings and the lake.
An annual migration of blue wildebeest and other bovids arrives at Lake Victoria to discover dry season forage. That is one of the biggest bovid migrations on the African continent.
An eco-hassle with a happier outcome became the fight towards the massive increase of water hyacinth (Eichhornia crassipes), a local of the tropical Americas, which bureaucracy thick mats of plant inflicting difficulties to transportation, fishing, hydroelectic electricity technology and ingesting water deliver. By 1995, 90% of the Ugandan shoreline was blanketed by the plant. With mechanical and chemical control of the hassle seeming not likely, the mottled water hyacinth weevil ( Neochetina eichhorniae) was bred and launched with excellent results.
Nalubaale dam
The most effective outflow for Lake Victoria is at Jinja, Uganda in which it forms the Victoria Nile. The water firstly tired over a natural rock weir. In 1954 British colonial engineers blasted out the weir and replaced it with the Owens Falls dam, now renamed the Nalubaale dam, turning the entire lake into a massive hydroelectric reservoir. A fashionable for mimicking the old fee of outflow called the "agreed curve" was mounted, placing the maximum drift price at 300 to 1700 cubic meters in keeping with 2d (392 - 2224 yd³/sec) depending at the lake's water level.
In 2002 Uganda finished a 2d hydroelectric complicated inside the vicinity. By 2006 the water tiers in Lake Victoria had reached an 80-12 months low, and Daniel Kull, a hydrologist with the UN's International Strategy for Disaster Reduction in Nairobi, Kenya, calculated that Uganda became exceeding the agreed curve by using 55% .
At 3500 cubic meters in step with 2nd (4578 yd³), greater than double the most agreed curve, it'd take a 12 months to drain one hundred ten.4 cubic km (89,500 acre-feet) from the lake. That is about 4% of the lake's quantity.
Transportation
Since the 1900s Lake Victoria ferries were an important method of transport among Uganda, Tanzania and Kenya. The important ports on the lake are Kisumu, Mwanza, Bukoba, Entebbe, Port Bell and Jinja. The steamer MV Bukoba sank inside the lake on May 21, 1996, killing nearly 1,000 people in one in every of Africa's worst maritime disasters.
References by Wikipedia
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