salt In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as r ...

alkaline In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The ...

Ngorongoro District Ngorongoro District (''Wilaya ya Ngorongoro'', in Swahili language, Swahili) is one of seven Districts of Tanzania, districts in western Arusha Region of Tanzania. The district is bordered to the north by Kenya, to the east by Monduli District, t ...

Arusha Region Arusha Region () is one of Tanzania's 31 administrative Regions of Tanzania, regions and is located in the northeast of the country. The region's capital and largest city is the city of Arusha. The region is bordered by Kajiado County and Narok C ...

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

Kenya Kenya, officially the Republic of Kenya, is a country located in East Africa. With an estimated population of more than 52.4 million as of mid-2024, Kenya is the 27th-most-populous country in the world and the 7th most populous in Africa. ...

East African Rift The East African Rift (EAR) or East African Rift System (EARS) is an active continental rift zone in East Africa. The EAR began developing around the onset of the Miocene, 22–25 million years ago. It was formerly considered to be part of a l ...

Ramsar Site A Ramsar site is a wetland site designated to be of international importance under the Ramsar Convention,8 ha (O) *** Permanent 8 ha (P) *** Seasonal Intermittent < 8 ha(Ts) **

lesser flamingo The lesser flamingo (''Phoeniconaias minor'') is a species of flamingo occurring in sub-Saharan Africa and western India. Birds are occasionally reported from further north, but these are generally considered vagrants. Characteristics The lesse ...

es, although this habitat is not protected and is under threat from planned development projects.

Description

This lake is fed principally by the Southern Ewaso Ng'iro River, which rises in central

Kenya Kenya, officially the Republic of Kenya, is a country located in East Africa. With an estimated population of more than 52.4 million as of mid-2024, Kenya is the 27th-most-populous country in the world and the 7th most populous in Africa. ...

, and by mineral-rich hot springs. It is quite shallow, less than deep, and varies in width depending on its water level. The lake is a maximum of long and wide. The surrounding area receives irregular seasonal rainfall, mainly between December and May totalling per year. Temperatures at the lake are frequently above . High levels of evaporation have left behind natron (

sodium carbonate Sodium carbonate (also known as washing soda, soda ash, sal soda, and soda crystals) is the inorganic compound with the formula and its various hydrates. All forms are white, odourless, water-soluble salts that yield alkaline solutions in water ...

decahydrate) and

trona Trona (trisodium hydrogendicarbonate dihydrate, also sodium sesquicarbonate dihydrate, Na2CO3·NaHCO3·2H2O) is a non- marine evaporite mineral. It is mined as the primary source of sodium carbonate in the United States, where it has replaced ...

(sodium sesquicarbonate dihydrate). The alkalinity of the lake can reach a pH of greater than 12. The surrounding bedrock is composed of alkaline, sodium-dominated

trachyte Trachyte () is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and aphanite, aphanitic (fine-grained), with minor amounts of mafic minerals, and is formed by the rapid cooling of lava (or shallow intrus ...

lavas that were laid down during the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

period. The lavas have significant amounts of

carbonate A carbonate is a salt of carbonic acid, (), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate group ...

but very low

calcium Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to it ...

and

magnesium Magnesium is a chemical element; it has Symbol (chemistry), symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 ...

levels. This has allowed the lake to concentrate into a caustic alkaline brine. The chemical properties of the water are known to calcify the bodies of any living thing that died in the lake.

Flora

The colour of the lake is characteristic of those where very high

evaporation Evaporation is a type of vaporization that occurs on the Interface (chemistry), surface of a liquid as it changes into the gas phase. A high concentration of the evaporating substance in the surrounding gas significantly slows down evapora ...

rates occur. As water evaporates during the dry season, salinity levels increase to the point that salt-loving

microorganism A microorganism, or microbe, is an organism of microscopic scale, microscopic size, which may exist in its unicellular organism, single-celled form or as a Colony (biology)#Microbial colonies, colony of cells. The possible existence of unseen ...

s begin to thrive. Such

halophile A halophile (from the Greek word for 'salt-loving') is an extremophile that thrives in high salt In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more ...

organisms include some

cyanobacteria Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis. The name "cyanobacteria" () refers to their bluish green (cyan) color, which forms the basis of cyanobacteri ...

that make their own food with

photosynthesis Photosynthesis ( ) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabo ...

as plants do. The red accessory photosynthesizing pigment in the cyanobacteria produces the deep reds of the open water of the lake and the orange colours of the shallow parts of the lake. The

alkali In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The a ...

salt crust on the surface of the lake is also often coloured red or pink by the

halophilic A halophile (from the Greek word for 'salt-loving') is an extremophile that thrives in high salt concentrations. In chemical terms, halophile refers to a Lewis acidic species that has some ability to extract halides from other chemical species. ...

microorganism A microorganism, or microbe, is an organism of microscopic scale, microscopic size, which may exist in its unicellular organism, single-celled form or as a Colony (biology)#Microbial colonies, colony of cells. The possible existence of unseen ...

s that live there.

Salt marsh A salt marsh, saltmarsh or salting, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. I ...

es and freshwater wetlands around the edges of the lake do support a variety of plants.

Fauna

Most animals find the lake's high temperature (up to ) and its high and variable salt content inhospitable. Nonetheless, Lake Natron is home to some

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

algae Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular ...

,

invertebrates Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordate subphylum ...

, and

birds Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

. In the slightly less salty water around its margins, some fish can also survive. The lake is the only regular breeding area in East Africa for the 2.5 million

lesser flamingo The lesser flamingo (''Phoeniconaias minor'') is a species of flamingo occurring in sub-Saharan Africa and western India. Birds are occasionally reported from further north, but these are generally considered vagrants. Characteristics The lesse ...

es, whose status of "near threatened" results from their dependence on this one location. When

salinity Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensio ...

increases, so do

cyanobacteria Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis. The name "cyanobacteria" () refers to their bluish green (cyan) color, which forms the basis of cyanobacteri ...

, and the lake can also support more nests. These flamingoes, the single large flock in East Africa, gather along nearby saline lakes to feed on '' Spirulina'' (a blue-green algae with red pigments). Lake Natron is a safe breeding location because its caustic environment is a barrier against predators trying to reach their nests on seasonally forming

evaporite An evaporite () is a water- soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as oce ...

islands. Greater flamingoes also breed on the mud flats. The lake has inspired the nature documentary '' The Crimson Wing: Mystery of the Flamingos'' by

Disneynature Disneynature is an independent film studio that specializes in the production of nature documentary films for Walt Disney Studios, a division of Disney Entertainment, which is owned by The Walt Disney Company. Disneynature was founded on April ...

, for its close relationship with the

Lesser flamingo The lesser flamingo (''Phoeniconaias minor'') is a species of flamingo occurring in sub-Saharan Africa and western India. Birds are occasionally reported from further north, but these are generally considered vagrants. Characteristics The lesse ...

es as their only regular breeding area. Two endemic fish species, the alkaline tilapias '' Alcolapia latilabris'' and '' A. ndalalani'', also thrive in the waters at the edges of the hot spring inlets. '' A. alcalica'' is also present in the lake, but is not endemic.

Threats and preservation

The area around the

salt lake A salt lake or saline lake is a landlocked body of water that has a concentration of salts (typically sodium chloride) and other dissolved minerals significantly higher than most lakes (often defined as at least three grams of salt per liter). I ...

is not inhabited but there is some herding and some seasonal cultivation. Threats to the salinity balance from increased siltation influxes will come from more projected logging in Natron watersheds and a planned

hydroelectric Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other Renewable energ ...

power plant A power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the electricity generation, generation of electric power. Power stations are generally connected to an electr ...

on the Ewaso Ng'iro across the border in

Kenya Kenya, officially the Republic of Kenya, is a country located in East Africa. With an estimated population of more than 52.4 million as of mid-2024, Kenya is the 27th-most-populous country in the world and the 7th most populous in Africa. ...

. Although development plans include constructions of a dike at the north end of the lake to contain the freshwater, the threat of dilution to this breeding ground may still be serious. There is no formal protection. A new threat to Lake Natron is the proposed development of a

soda ash Sodium carbonate (also known as washing soda, soda ash, sal soda, and soda crystals) is the inorganic compound with the formula and its various hydrates. All forms are white, odourless, water-soluble salts that yield alkaline solutions in water ...

plant on its shores. The plant would pump water from the lake and extract the sodium carbonate to convert to washing powder for export. Accompanying the plant would be housing for over 1000 workers, and a coal-fired power station to provide energy for the plant complex. In addition, there is a possibility the developers may introduce a hybrid

brine shrimp ''Artemia'' is a genus of aquatic crustaceans also known as brine shrimp or ''Sea-Monkeys, sea monkeys''. It is the only genus in the Family (biology), family Artemiidae. The first historical record of the existence of ''Artemia'' dates back to t ...

to increase the efficiency of extraction. According to Chris Magin, the RSPB's international officer for Africa, "The chance of the lesser flamingoes continuing to breed in the face of such mayhem are next to zero. This development will leave lesser flamingoes in East Africa facing extinction". Seventy-five percent of the world's lesser flamingoes are born on Lake Natron. Currently a group of more than fifty East African conservation and environmental institutions are running a worldwide campaign to stop the planned construction of the soda ash factory by Tata Chemicals Ltd of Mumbai, India, and National Development Corporation of Tanzania. The group working under the umbrella name Lake Natron Consultative Group is being co-ordinated by Ken Mwathe, Conservation Programme Manager at

BirdLife International BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding i ...

's Africa Secretariat. As per communication in June 2008, Tata Chemicals shall not proceed with the Natron Project and further re-examination of this project will be subject to the Ramsar Wetlands plan, which is currently under preparation. Because of its unique biodiversity, Tanzania named the Lake Natron Basin to the

Ramsar List of Wetlands of International Importance Ramsar sites are protected under by the Ramsar Convention, an international treaty for the conservation movement, conservation and sustainable use of wetlands, recognizing the fundamental ecological functions of wetlands and their economic, cultura ...

on 4 July 2001. The lake is also the

World Wildlife Fund The World Wide Fund for Nature (WWF) is a Swiss-based international non-governmental organization founded in 1961 that works in the field of wilderness preservation and the reduction of human impact on the environment. It was formerly named the ...

East African halophytics

ecoregion An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and quantity of environmental resources. Ecoregions cover relatively large areas of land or water, and c ...

.

Visiting the area

There are a number of campgrounds near the lake, which is also the base for climbing Ol Doinyo Lengai. Lake Natron has tourist attraction potentials that are important for

ecotourism Ecotourism is a form of nature-oriented tourism intended to contribute to the Ecological conservation, conservation of the natural environment, generally defined as being minimally impactful, and including providing both contributions to conserv ...

development. However, lack of a general management plan, inadequate funding at the operational level, lack of mechanisms to secure a fair distribution of ecotourism benefits, and poorly developed tourism infrastructural facilities to support diverse segments of tourists were identified as the main challenges associated with the management of ecotourism in the area. The lake can also be accessed from Shompole Conservancy

Kenya Kenya, officially the Republic of Kenya, is a country located in East Africa. With an estimated population of more than 52.4 million as of mid-2024, Kenya is the 27th-most-populous country in the world and the 7th most populous in Africa. ...

.

References

External links

*
Think Pink – Save Africa's FlamingosNBC article about Nick Brandt's photos of petrified animals at Natron lake
* * {{DEFAULTSORT:Natron, Lake Lakes of Tanzania Ramsar sites in Tanzania Saline lakes of the Great Rift Valley Geography of Arusha Region Southern Eastern Rift Important Bird Areas of Tanzania

Description

Flora

Fauna

Threats and preservation

Visiting the area

See also

References

External links