Lake Turkana, also known as the Jade Sea, is a vast and unique body of water located in the Kenyan Rift Valley. It is the world’s largest permanent desert lake, the world’s largest alkaline lake, and the fourth-largest salt lake in the world. The lake is home to a diverse array of flora and fauna, including Nile crocodiles and hundreds of species of birds. It is also an important area for studying human evolution, with numerous hominid fossils being discovered in the region. In recognition of its importance, Lake Turkana was designated as a UNESCO World Heritage Site in 1997.
The history and geology of Lake Turkana are fascinating and complex, with a rich human and natural history that has shaped the region into what it is today. The lake has been known by many names over the years, including Lake Rudolf, named after Crown Prince Rudolf of Austria, and Basso Narok, meaning “Black Lake” in the Samburu language. The surrounding area is predominantly volcanic, with outcrops and rocky shores found on the eastern and southern shores of the lake and dunes, spits, and flats on the western and northern shores.
Despite its remote location and harsh climate, the region around Lake Turkana has long been inhabited by various cultures. The lake is home to several indigenous tribes, including the Turkana, Rendille, Gabbra, Daasanach, Hamar Koke, Karo, Nyagatom, Mursi, Surma, and Molo. Each of these cultures has unique traditions and ways of life, and the lake has played a central role in their history and culture.
In this article, we will explore Lake Turkana’s fascinating history and geology, delving into its geologic formation, human history, and the rich diversity of life it supports. From its ancient connections to the Nile River to its modern-day role as a source of hydroelectric power, Lake Turkana is truly remarkable and fascinating.
History of Lake Turkana
Lake Turkana, located in the Kenyan Rift Valley, has a long and fascinating history that dates back millions of years. The lake is home to a diverse array of flora and fauna and has been an important source of water and resources for the local communities for centuries.
The lake was originally named Lake Rudolf by Count Sámuel Teleki de Szék and Lieutenant Ludwig Ritter Von Höhnel in 1888 in honor of Crown Prince Rudolf of Austria. The lake was renamed Lake Turkana in 1975 by Kenyan President Mzee Jomo Kenyatta, after the Turkana people, the dominant tribe in the region.
The lake’s geology is equally fascinating, with the lake being a part of the East African Rift System. The rift began to form millions of years ago as the East African plate separated from the rest of Africa. The rift is also accompanied by a graben, or trough, in which lake water can collect. The basement rocks of the region were dated back to 522 and 510 million years ago, and the oldest volcanic activity in the region occurred in the Nabwal Hills northeast of Turkana around 34.8 million years ago.
Over time, the lake has undergone significant fluctuations in water level, with periods of high water levels followed by drops of more than 40 meters in just 200 years. These changes have had a significant impact on the lake’s ecosystem, as well as the surrounding communities that rely on the lake for water and resources.
Despite its harsh and remote location, Lake Turkana has played a vital role in human history and the study of human evolution. The lake region is believed to have been an evolutionary nest of hominins. Many thousands of fossils have been excavated from the area, including those of early hominids such as Homo habilis and Homo erectus.
Today, Lake Turkana is threatened by the construction of the Gilgel Gibe III Dam in Ethiopia, which has the potential to significantly reduce the lake’s water levels and impact the local communities and ecosystems. Despite these challenges, the lake remains a unique and important natural wonder that continues to captivate and intrigue those who visit.
Geology of Lake Turkana
Lake Turkana is located in the East African Rift Valley, a weak point in the Earth’s crust caused by the separation of two tectonic plates. The rift began when East Africa moved away from the rest of Africa to the northeast. The graben, or trough, where Lake Turkana is located is 320 km wide in the north and 170 km in the south.
The oldest volcanic activity in the region occurred in the Nabwal Hills north of Turkana and dates to 34.8 million years ago in the late Eocene period. Extensive basalt extrusions over the Turkana-Omo Basin occurred between 4.18 and 3.99 million years ago, forming the Gombe Group Basalts. These basalts are divided into the Mursi Basalts and the Gombi Basalts and form the rocky mountains and badlands around the lake.
Fluctuations in lake level and volcanic ash spewings have resulted in a layering of the ground cover over the basal rocks. These layers can be precisely dated through chemical analysis of the tuff. As the region is believed to have been an important location for hominin evolution, these dates are important for understanding the diachronic array of fossils found in the area, both hominoid and non-hominoid. Ancient shorelines, or terraces, can also be seen in the Turkana Basin, with the highest being 100 meters above the current surface of the lake, which occurred about 9,500 years ago.
The Lake Turkana drainage basin draws its waters mainly from the Kenya Highlands and Ethiopian Highlands. The lake has a unique feature as it is the only lake that retains the waters originating from two separate catchment areas of the Nile. The lake is also classified as a desert lake, with the surrounding region classified as desert and xeric shrubland. The Chalbi Desert is located east of the lake.
Biological Diversity of Lake Turkana
Lake Turkana is home to a diverse array of plant and animal life, with many species found nowhere else in the world. The lake is an aquatic biome, and the surrounding region is classified as desert and xeric shrubland. The major biomes of the lake include the lake itself and the surrounding Chalbi Desert.
The lake is home to various plankton, including cyanobacteria and microalgae, copepods, cladocerans, and protozoans. Lake Turkana is also home to about 50 fish species, including 12 endemics. Non-endemic species include Nile tilapia, mango tilapia, bichirs, elephantfish, African Arowana, African knife fish, and Nile perch.
The region surrounding Lake Turkana is home to hundreds of species of birds, including little stints, wood sandpipers, and common sandpipers. The lake is also home to a large population of Nile crocodiles and large water turtles, particularly on Central Island. The Turkana mud turtle is endemic to the lake.
Over the dry grasslands of the region, one can find a variety of grazing mammals and predators, including Grevy’s zebra, Burchell’s zebra, beisa oryx, Grant’s gazelle, topi, and reticulated giraffe. These animals are hunted by predators such as lions and cheetahs. Elephants and black rhinoceroses are no longer found in the region but were once present. Smaller mammals, such as the cushioned gerbil, can also be found in the area.
In summary, the biological diversity of Lake Turkana is diverse and varied, with many species of plants and animals found nowhere else in the world. From the rich plankton populations of the lake to the diverse array of mammal and bird species found in the surrounding region, Lake Turkana is a true treasure of biological diversity.
Threats to Lake Turkana
Lake Turkana is home to rich and diverse flora and fauna. It is known for its large population of Nile crocodiles and various fish species and its varied bird population. The surrounding region is classified as a desert and xeric shrubland, with dry grasslands appearing during moister times and dwarf shrubs such as Duosperma eremophilum and Indigofera Spinosa appearing during drier times. The lake is also home to the Turkana mud turtle, which is endemic.
Despite its rich biological diversity, Lake Turkana is facing several threats. One major threat is the construction of the Gilgel Gibe III Dam in Ethiopia, which will dam the Omo River, the main source of water for the lake. This can significantly decrease the lake’s water level, which could negatively impact the lake’s ecosystems and the communities that depend on it. Another threat is overfishing, which has already negatively impacted the lake’s fish populations. Climate change is also a concern, as rising temperatures and changing rainfall patterns could impact the lake’s ecosystems.
Protecting and preserving Lake Turkana and its unique and diverse ecosystems is important for future generations. This will require addressing these threats and implementing conservation efforts to ensure the lake’s long-term health.
Conclusion
In conclusion, Lake Turkana is a unique and fascinating place with a rich history and geology. From its ancient origins as part of the Nile River system to its current status as the world’s largest permanent desert lake, it has played a significant role in the natural and human history of the region.
Its biological diversity, including its large populations of Nile crocodiles and various fish species, make it an important ecosystem that must be protected. However, it is currently facing several threats, including the construction of the Gilgel Gibe III Dam and overfishing, which could have negative impacts on the lake and the communities that depend on it. It is important to address these threats and implement conservation efforts to ensure the long-term health and sustainability of Lake Turkana and its ecosystems.
