Wouri estuary
Encyclopedia
The Wouri estuary, or Cameroon estuary is a large tidal estuary in Cameroon
where several rivers come together, emptying into the Bight of Biafra. Douala
, the largest city in Cameroon, is at the mouth of the Wouri River
where it enters the estuary. The estuary contains extensive mangrove
forests, which are being damaged by pollution and population pressures.
and empties into the Bight of Biafra. It is fed by the Mungo
, Wouri
and Dibamba
rivers.
The estuary lies in the Douala Basin, a low-lying depression about 30 metres (98.4 ft) on average about sea level, with many creeks, sand bars and lagoons.
The Plio-Pleistocene
Wouri alluvial aquifer, a multi-layer system with alternating sequences of marine sands and estuarine mud and silt lies below the estuary and surrounding region and is an important source of well water. The upper aquifer in this system is an unconfined sandy horizon that is hydraulically connected to the brackish waters of the estuary and to the coastal wetlands.
The spring tides at the mouth of the estuary are 2.8 metres (9.2 ft).
Rainfall is from 4000 millimetres (157.5 in) to 5000 millimetres (196.9 in) annually.
Salinity is very low, particularly during the rainy season. Surface salinity of 0.4% is common around Douala throughout the year.
The Mungo river splits into numerous small channels that empty into the estuary complex.
The tidal wave in the bay travels as far as 40 kilometres (24.9 mi) up the Mungo. In this section of the river, large flats and sand banks are exposed at low tide.
The Wouri is affected by the tides for 45 kilometres (28 mi) above Douala, with blocks of tidal forest along its shores throughout this stretch.
To the west of the estuary, the slopes of Mount Cameroon are covered with banana plantations. To the northeast, the mangroves are backed by freshwater tidal swamps 5 kilometres (3.1 mi) wide.
One block of freshwater swamp between Muyuka and Dibombari covers 7500 hectares (18,532.9 acre).
There are still some patches of permanent swamp forest on the Dibamba river, but many others have been cleared and drained for oil palm plantation. The river's fauna
are not well protected; particularly endangered is the African Manatee (Trichechus senegalensis).
.
The mudflats and mangrove forests are home to many waterbirds, and are breeding grounds for fish, shrimp and other wildlife.
They can be classified as wetlands of international importance according to criteria under the Ramsar convention.
The estuary is home to the Cameroon ghost shrimp, which periodically irrupts into dense swarms.
At these times, people catch huge quantities, eating the females or drying them for later use, and making a fish oil from the males.
The country takes its name from the shrimp. Portuguese explorers named the estuary Rio dos Camarãos (shrimp river), and this name evolved into the modern "Cameroon".
There are 188000 hectares (464,557.7 acre) in total of mangrove forest in the estuary.
A large block of mangroves 20 kilometres (12.4 mi) deep on the north shore extends 35 kilometres (21.7 mi) up-estuary. The mangrove forest is broken by Bodeaka Bay and Moukouchou Bay, which form wide waterways through the swamp.
On the south shore of the estuary, mangroves extend from Douala to Point Soulelaba, the end of the spit that separates the estuary from the sea. These mangroves are divided by the Dibamba River and by Monaka Bay and Island.
About 15000 hectares (37,065.8 acre) of the mangrove forest is within the Mouanko Reserve, which extends from the south shore of the estuary to the Sanaga River mouth.
The mangrove Rhizophora racemosa
, which makes up over 90% of mangroves in Cameroon, reaches a height of 40 metres (131.2 ft) in the Wouri estuary.
Nypa fruticans
, an exotic species imported to Nigeria
from from South-East Asia, has been spreading quickly, encouraged by the local people.
The mangrove forests are an important source of wood for making furniture and fences, for smoking fish and for fuel. The leaves of Nypa fruticans are used for thatching
house walls and roofs.
The mangroves act as a buffer zone, protecting the coast against the worst effects of storms.
However, there are no effective controls on mangrove logging, and the Wouri estuary has undergone substantial deforestation.
The estuary has traditionally been home to a number of different ethnic groups including the Duala people
around the mouth of the Wouri river, the Limba people
in the southeast and around the mouth of the Sanaga River
, the Mungo people
in the north and west of the estuary and the Isubu people in the southwest.
These people originally lived through agriculture and fishing.
The first Portuguese
explorer, Fernando Po
, arrived in the estuary in 1472.
He was soon followed by traders from Portugal and other European countries.
The people of the estuary became trading intermediaries, carrying European goods to the inland regions by canoe and bringing back ivory, slaves and palm products.
Ivory was obtained from the Bamenda Grassfields, to the north.
The slave trade began in the 18th century, and was an important economic activity by 1750.
Slaves captured in the Chamba wars were brought from the Grassfields via the Mungo River
, and slaves from the Nun-Mbam country to the northeast were brought via the Wouri. The Dutch
were the main purchasers of slaves in the estuary in the mid-18th century.
By the 1830s, the slave trade was in terminal decline due to reduced demand from the United States
and punitive action by the British
based on the island of Fernando Po
.
By the mid 19th century, palm oil and palm kernels had become the main trade goods.
The Duala were the leading traders. They prevented European access to the interior and built efficient trade networks.
The Duala used marriage ties with the people of the interior to establish trust, with the children of the marriages acting as their agents.
At the request of King Bell
and King Akwa of the Duala, the estuary was annexed by Germany
in 1884, becoming the nucleus of the colony of Kamerun
.
The Germans slowly extended their control over the estuary and the vast hinterland of Kamerun over a period of 25 years.
At the start of the First World War in 1914, a British expedition from Nigeria
won control of the colony. In 1916, Kamerun was divided, with the British
taking the lands to the west of the Mungo and the French
taking the lands to the east.
In the 1920s, the French improved infrastructure, dredging the estuary to improve access to the port of Douala and rebuilding railways that connected the city to the interior.
After the Second World War, the French built a road/rail bridge across the Wouri river, linking Douala and Bonaberi, deepened the shipping canals in the estuary, converted Bonaberi into a banana port and expanded the capacity of Douala port to 900,000 tons, making it the third largest port on the West African coast.
The people of the estuary were reunited in 1961 when the modern state of Cameroon was created from the former French Colony and the southern portion of the British colony.
The early settlements of the Duala people at the mouth of the Wouri river - Belltown, Akwatown, Bonapriso, Deido and Bonaberi - have been absorbed by Douala
, a city of over three million people that now contains many different ethnic groups, typically each concentrated in their own neighborhoods.
Infrastructure such as roads, water supplies, sewage and electricity is poor and in some areas non-existent. Most of the inhabitants work for low wages in informal commercial and industrial enterprises.
The port of Douala is limited in its capacity due to its location on the river Wouri, which carries heavy loads of sediment and needs constant dredging.
Outside the city, the settlements in the estuary region are villages accessible only by water.
Sources of pollution include electroplating and oil refinery industries, pest control in cocoa, coffee and banana plantations, and waste organic oils from land transport, process industries and power generation.
The bulk of human-generated sewage is also released into the estuary without treatment.
The government infrastructure for controlling pollution is dispersed, weak and ineffective, and there is severe shortage of funding.
Agriculture is the mainstay of the Cameroon economy. Pesticides are not regulated, and also contribute to pollution. Pesticides that have long been banned elsewhere are still in use, or are being held in leaky storage facilities.
The growing population is increasing production of export crops such as coffee, cocoa, bananas, palm oil and cotton, using imported pesticides and fertilizers. Typically fertilizers contain urea, ammonia, and phosphorus. Pesticides applied are mostly DDT
and other derivatives of organohalogens.
About 95% of Cameroon's industries are based in or around Douala.
Their liquid waste is released into the estuary with little or no treatment.
Douala's Bassa industrial zone ends in the estuarine creek formation of the Dibamba River, discharging pollutants. The wetlands are quickly being colonized by invasive species, and a great number of phytoplankton
have been identified, some of which are caused by the pollution.
The Bonaberi suburb of Douala, with a rapidly growing population of over 500,000, illustrates the urban environmental problems.
More than 75% of Bonaberi is 2 metres (6.6 ft) above sea level on average.
With limited land, poor people have encroached into wetlands.
As of 2002, the dense mangrove swamp forest, which included luxuriant growths of palms, was undergoing extinction due to urbanization.
The houses and industrial buildings on the cleared land are poorly built, without adequate drainage.
Pools of stagnant water are breeding grounds for disease.
Human and industrial waste end up in the channels of the Wouri, reducing its rate of flow.
River floods and sea incursions may cause rises of water level from 2 metres (6.6 ft) to 5 metres (16.4 ft) within a few minutes, destroying buildings and washing raw sewage into the wells. Waterborne diseases such as typhus
and dysentery
are common causes of death.
Fishery is economically of great importance to Cameroon, with about 40,000 tonnes caught each year, of which one third is exported.
In 1994, US$60 million worth of fish was exported to Europe, three quarters of which came from 12 industrial-scale fishing companies.
About 40% of the workforce in coastal Cameroon are full-time unregistered fishers.
Fish contributes about 44% of the protein in the local population's diet.
The mangroves of the estuary are spawning grounds for many types of commercial fish, but they are not protected.
The area covered by mangroves continues to shrink and the fish population has been declining steadily.
Levels of persistent organic pollutants in the fish are rising.
A 1991 study showed excessive levels of DDTs and PCBs in fish, shrimp and oysters in the area around Douala.
High pollution loads of heavy metals such as mercury, lead and cadmium are also a concern.
The Matanda block in the northern half of the estuary and the surrounding region has estimated reserves of between 60 and 300 million barrels.
Exploratory work by Gulf Oil
several decades ago indicated that production of 4 million barrels a year could be feasible.
In April 2008, a subsidiary of Swiss
firm Glencore International AG and Afex Global Limited signed a deal with the Cameroon state oil company for a $38 million exploration project in the 1187 square kilometres (458.3 sq mi) zone, which was approved by Badel Ndanga Ndinga, Minister of Industries, Mines and Technological Development.
|title=Cameroon
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|accessdate=2011-02-24}}
|url=http://www.entrepreneurnewsonline.com/2008/04/glencore-afex-s.html
|date=April 11, 2008
|title=Glencore, Afex sign exploration deal with Cameroon
|work=The Entrepreneur
|accessdate=2011-02-27}}
|url=http://nlbif.eti.uva.nl/bis/lobsters.php?menuentry=soorten&id=73
|title=Callianassa turnerana
|first=Lipke B. |last=Holthuis |authorlink=Lipke Holthuis
|work=Netherlands Biodiversity Information Facility
|accessdate=2011-02-27}}
|url=http://www.waltersmunde.com/papers/PESTICIDEUSEINCAMEROON.pdf
|first=Walters |last=Munde
|title=Pesticide Use in Cameroon
|accessdate=2011-02-27}}
Cameroon
Cameroon, officially the Republic of Cameroon , is a country in west Central Africa. It is bordered by Nigeria to the west; Chad to the northeast; the Central African Republic to the east; and Equatorial Guinea, Gabon, and the Republic of the Congo to the south. Cameroon's coastline lies on the...
where several rivers come together, emptying into the Bight of Biafra. Douala
Douala
Douala is the largest city in Cameroon and the capital of Cameroon's Littoral Province. Home to Cameroon's largest port and its major international airport, Douala International Airport, it is the commercial capital of the country...
, the largest city in Cameroon, is at the mouth of the Wouri River
Wouri River
The Wouri is a river in Cameroon. The river is formed at the confluence of the rivers Nkam and Makombé, northeast of the city of Yabassi. The Wouri then flows about southeast to the Wouri estuary at Douala, the chief port and industrial city in the southwestern part of Cameroon on the Gulf of...
where it enters the estuary. The estuary contains extensive mangrove
Mangrove
Mangroves are various kinds of trees up to medium height and shrubs that grow in saline coastal sediment habitats in the tropics and subtropics – mainly between latitudes N and S...
forests, which are being damaged by pollution and population pressures.
Hydrology
The estuary lies to the east of Mount CameroonMount Cameroon
Mount Cameroon is an active volcano in Cameroon near the Gulf of Guinea. Mount Cameroon is also known as Cameroon Mountain or Fako or by its native name Mongo ma Ndemi ....
and empties into the Bight of Biafra. It is fed by the Mungo
Mungo River, Cameroon
The Mungo River is a large river in Cameroon that drains the mountains in the southern portion of the Cameroon line of active and extinct volcanoes.-Course:The Mungo river has a catchment area of ....
, Wouri
Wouri River
The Wouri is a river in Cameroon. The river is formed at the confluence of the rivers Nkam and Makombé, northeast of the city of Yabassi. The Wouri then flows about southeast to the Wouri estuary at Douala, the chief port and industrial city in the southwestern part of Cameroon on the Gulf of...
and Dibamba
Dibamba River
The Dibamba River is in the Littoral Region of southern Cameroon, emptying into the Cameroon estuary near the city of Doula.-Location:The Dibamba river has a length of and a catchment area of...
rivers.
The estuary lies in the Douala Basin, a low-lying depression about 30 metres (98.4 ft) on average about sea level, with many creeks, sand bars and lagoons.
The Plio-Pleistocene
Plio-Pleistocene
The term Plio-Pleistocene refers to the geological period more recent than circa 5 million years ago, incorporating both the formally defined epochs of the Pliocene and the Pleistocene...
Wouri alluvial aquifer, a multi-layer system with alternating sequences of marine sands and estuarine mud and silt lies below the estuary and surrounding region and is an important source of well water. The upper aquifer in this system is an unconfined sandy horizon that is hydraulically connected to the brackish waters of the estuary and to the coastal wetlands.
The spring tides at the mouth of the estuary are 2.8 metres (9.2 ft).
Rainfall is from 4000 millimetres (157.5 in) to 5000 millimetres (196.9 in) annually.
Salinity is very low, particularly during the rainy season. Surface salinity of 0.4% is common around Douala throughout the year.
The Mungo river splits into numerous small channels that empty into the estuary complex.
The tidal wave in the bay travels as far as 40 kilometres (24.9 mi) up the Mungo. In this section of the river, large flats and sand banks are exposed at low tide.
The Wouri is affected by the tides for 45 kilometres (28 mi) above Douala, with blocks of tidal forest along its shores throughout this stretch.
To the west of the estuary, the slopes of Mount Cameroon are covered with banana plantations. To the northeast, the mangroves are backed by freshwater tidal swamps 5 kilometres (3.1 mi) wide.
One block of freshwater swamp between Muyuka and Dibombari covers 7500 hectares (18,532.9 acre).
There are still some patches of permanent swamp forest on the Dibamba river, but many others have been cleared and drained for oil palm plantation. The river's fauna
Fauna
Fauna or faunæ is all of the animal life of any particular region or time. The corresponding term for plants is flora.Zoologists and paleontologists use fauna to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess shale fauna"...
are not well protected; particularly endangered is the African Manatee (Trichechus senegalensis).
Fauna and flora
The estuary is a global marine biodiversity hotspotBiodiversity hotspot
A biodiversity hotspot is a biogeographic region with a significant reservoir of biodiversity that is under threat from humans.The concept of biodiversity hotspots was originated by Norman Myers in two articles in “The Environmentalist” , revised after thorough analysis by Myers and others in...
.
The mudflats and mangrove forests are home to many waterbirds, and are breeding grounds for fish, shrimp and other wildlife.
They can be classified as wetlands of international importance according to criteria under the Ramsar convention.
The estuary is home to the Cameroon ghost shrimp, which periodically irrupts into dense swarms.
At these times, people catch huge quantities, eating the females or drying them for later use, and making a fish oil from the males.
The country takes its name from the shrimp. Portuguese explorers named the estuary Rio dos Camarãos (shrimp river), and this name evolved into the modern "Cameroon".
There are 188000 hectares (464,557.7 acre) in total of mangrove forest in the estuary.
A large block of mangroves 20 kilometres (12.4 mi) deep on the north shore extends 35 kilometres (21.7 mi) up-estuary. The mangrove forest is broken by Bodeaka Bay and Moukouchou Bay, which form wide waterways through the swamp.
On the south shore of the estuary, mangroves extend from Douala to Point Soulelaba, the end of the spit that separates the estuary from the sea. These mangroves are divided by the Dibamba River and by Monaka Bay and Island.
About 15000 hectares (37,065.8 acre) of the mangrove forest is within the Mouanko Reserve, which extends from the south shore of the estuary to the Sanaga River mouth.
The mangrove Rhizophora racemosa
Rhizophora
Rhizophora is a genus of tropical mangrove trees, sometimes collectively called true mangroves. The most notable species is the Red Mangrove but some other species and a few natural hybrids are known. Rhizophora species generally live in intertidal zones which are indundated daily by the ocean...
, which makes up over 90% of mangroves in Cameroon, reaches a height of 40 metres (131.2 ft) in the Wouri estuary.
Nypa fruticans
Nypa fruticans
Nypa fruticans, known as the attap palm , nipa palm , and mangrove palm or buah atap , buah nipah , dừa nước , Ging Pol in Sinhala in Sri Lanka and gol pata , dani . It is the only palm considered a mangrove in the Mangroves Biome...
, an exotic species imported to Nigeria
Nigeria
Nigeria , officially the Federal Republic of Nigeria, is a federal constitutional republic comprising 36 states and its Federal Capital Territory, Abuja. The country is located in West Africa and shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in...
from from South-East Asia, has been spreading quickly, encouraged by the local people.
The mangrove forests are an important source of wood for making furniture and fences, for smoking fish and for fuel. The leaves of Nypa fruticans are used for thatching
Thatching
Thatching is the craft of building a roof with dry vegetation such as straw, water reed, sedge , rushes, or heather, layering the vegetation so as to shed water away from the inner roof. It is a very old roofing method and has been used in both tropical and temperate climates...
house walls and roofs.
The mangroves act as a buffer zone, protecting the coast against the worst effects of storms.
However, there are no effective controls on mangrove logging, and the Wouri estuary has undergone substantial deforestation.
History
Duala people
The Duala are an ethnic group of Cameroon. They primarily inhabit the littoral region to the coast and form a portion of the Sawa, or Cameroonian coastal peoples...
around the mouth of the Wouri river, the Limba people
Limba people (Cameroon)
The Limba are an ethnic group of the Republic of Cameroon. They belong to the Sawa peoples, those of the Cameroonian coast.-History and geography:...
in the southeast and around the mouth of the Sanaga River
Sanaga River
The Sanaga River is a river of South Province, Cameroon, Centre Province, Cameroon, and West Province, Cameroon. Its length is 890 kilometers.The Sanaga River forms a boundary between two tropical moist forest ecoregions...
, the Mungo people
Mungo people
The Mungo is an ethnic group of the Republic of Cameroon. Along with the other coastal peoples, they belong to the Sawa ethnic groups. The Mungo have historically been dominated by the Duala people, and the two groups share similar cultures, histories, and claims of origin.-History and...
in the north and west of the estuary and the Isubu people in the southwest.
These people originally lived through agriculture and fishing.
The first Portuguese
Portuguese people
The Portuguese are a nation and ethnic group native to the country of Portugal, in the west of the Iberian peninsula of south-west Europe. Their language is Portuguese, and Roman Catholicism is the predominant religion....
explorer, Fernando Po
Fernão do Pó
Fernão do Pó , also Fernão Pó, Fernando Pó, Fernando Poo was a Portuguese navigator and explorer of the West African coast. He discovered the islands in the Gulf of Guinea around 1472, one of which until the mid 1900s bore a version of his name, Fernando Pó or Fernando Poo. The island is...
, arrived in the estuary in 1472.
He was soon followed by traders from Portugal and other European countries.
The people of the estuary became trading intermediaries, carrying European goods to the inland regions by canoe and bringing back ivory, slaves and palm products.
Ivory was obtained from the Bamenda Grassfields, to the north.
The slave trade began in the 18th century, and was an important economic activity by 1750.
Slaves captured in the Chamba wars were brought from the Grassfields via the Mungo River
Mungo River
The Mungo River is a river of the West Coast Region of New Zealand's South Island. The major source of the Hokitika River, it flows generally west from the Southern Alps, becoming the Hokitika River at the point where it turns north as it flows through a gap in the Diedrich Range...
, and slaves from the Nun-Mbam country to the northeast were brought via the Wouri. The Dutch
Dutch people
The Dutch people are an ethnic group native to the Netherlands. They share a common culture and speak the Dutch language. Dutch people and their descendants are found in migrant communities worldwide, notably in Suriname, Chile, Brazil, Canada, Australia, South Africa, New Zealand, and the United...
were the main purchasers of slaves in the estuary in the mid-18th century.
By the 1830s, the slave trade was in terminal decline due to reduced demand from the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and punitive action by the British
British Empire
The British Empire comprised the dominions, colonies, protectorates, mandates and other territories ruled or administered by the United Kingdom. It originated with the overseas colonies and trading posts established by England in the late 16th and early 17th centuries. At its height, it was the...
based on the island of Fernando Po
Bioko
Bioko is an island 32 km off the west coast of Africa, specifically Cameroon, in the Gulf of Guinea. It is the northernmost part of Equatorial Guinea with a population of 124,000 and an area of . It is volcanic with its highest peak the Pico Basile at .-Geography:Bioko has a total area of...
.
By the mid 19th century, palm oil and palm kernels had become the main trade goods.
The Duala were the leading traders. They prevented European access to the interior and built efficient trade networks.
The Duala used marriage ties with the people of the interior to establish trust, with the children of the marriages acting as their agents.
At the request of King Bell
King Bell
King Bell may refer to several Cameroonian rulers:*Henri Lobe Bell*Ndumbe Lobe Bell*Manga Ndumbe Bell *Rudolf Duala Manga Bell *Richard Ndumbe Manga Bell*Alexandre Douala Manga Bell...
and King Akwa of the Duala, the estuary was annexed by Germany
German Empire
The German Empire refers to Germany during the "Second Reich" period from the unification of Germany and proclamation of Wilhelm I as German Emperor on 18 January 1871, to 1918, when it became a federal republic after defeat in World War I and the abdication of the Emperor, Wilhelm II.The German...
in 1884, becoming the nucleus of the colony of Kamerun
Kamerun
German Cameroon was a West African colony of the German Empire from 1884 to 1916 in the region of today's Republic of Cameroon.-History:-1800s:...
.
The Germans slowly extended their control over the estuary and the vast hinterland of Kamerun over a period of 25 years.
At the start of the First World War in 1914, a British expedition from Nigeria
Nigeria
Nigeria , officially the Federal Republic of Nigeria, is a federal constitutional republic comprising 36 states and its Federal Capital Territory, Abuja. The country is located in West Africa and shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in...
won control of the colony. In 1916, Kamerun was divided, with the British
British Empire
The British Empire comprised the dominions, colonies, protectorates, mandates and other territories ruled or administered by the United Kingdom. It originated with the overseas colonies and trading posts established by England in the late 16th and early 17th centuries. At its height, it was the...
taking the lands to the west of the Mungo and the French
French colonial empire
The French colonial empire was the set of territories outside Europe that were under French rule primarily from the 17th century to the late 1960s. In the 19th and 20th centuries, the colonial empire of France was the second-largest in the world behind the British Empire. The French colonial empire...
taking the lands to the east.
In the 1920s, the French improved infrastructure, dredging the estuary to improve access to the port of Douala and rebuilding railways that connected the city to the interior.
After the Second World War, the French built a road/rail bridge across the Wouri river, linking Douala and Bonaberi, deepened the shipping canals in the estuary, converted Bonaberi into a banana port and expanded the capacity of Douala port to 900,000 tons, making it the third largest port on the West African coast.
The people of the estuary were reunited in 1961 when the modern state of Cameroon was created from the former French Colony and the southern portion of the British colony.
The early settlements of the Duala people at the mouth of the Wouri river - Belltown, Akwatown, Bonapriso, Deido and Bonaberi - have been absorbed by Douala
Douala
Douala is the largest city in Cameroon and the capital of Cameroon's Littoral Province. Home to Cameroon's largest port and its major international airport, Douala International Airport, it is the commercial capital of the country...
, a city of over three million people that now contains many different ethnic groups, typically each concentrated in their own neighborhoods.
Infrastructure such as roads, water supplies, sewage and electricity is poor and in some areas non-existent. Most of the inhabitants work for low wages in informal commercial and industrial enterprises.
The port of Douala is limited in its capacity due to its location on the river Wouri, which carries heavy loads of sediment and needs constant dredging.
Outside the city, the settlements in the estuary region are villages accessible only by water.
Environmental issues
The ecology of the estuary is under threat from growing pollution from industry, farming and households, threatening both fish yields and human health.Sources of pollution include electroplating and oil refinery industries, pest control in cocoa, coffee and banana plantations, and waste organic oils from land transport, process industries and power generation.
The bulk of human-generated sewage is also released into the estuary without treatment.
The government infrastructure for controlling pollution is dispersed, weak and ineffective, and there is severe shortage of funding.
Agriculture is the mainstay of the Cameroon economy. Pesticides are not regulated, and also contribute to pollution. Pesticides that have long been banned elsewhere are still in use, or are being held in leaky storage facilities.
The growing population is increasing production of export crops such as coffee, cocoa, bananas, palm oil and cotton, using imported pesticides and fertilizers. Typically fertilizers contain urea, ammonia, and phosphorus. Pesticides applied are mostly DDT
DDT
DDT is one of the most well-known synthetic insecticides. It is a chemical with a long, unique, and controversial history....
and other derivatives of organohalogens.
About 95% of Cameroon's industries are based in or around Douala.
Their liquid waste is released into the estuary with little or no treatment.
Douala's Bassa industrial zone ends in the estuarine creek formation of the Dibamba River, discharging pollutants. The wetlands are quickly being colonized by invasive species, and a great number of phytoplankton
Phytoplankton
Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek words φυτόν , meaning "plant", and πλαγκτός , meaning "wanderer" or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye...
have been identified, some of which are caused by the pollution.
The Bonaberi suburb of Douala, with a rapidly growing population of over 500,000, illustrates the urban environmental problems.
More than 75% of Bonaberi is 2 metres (6.6 ft) above sea level on average.
With limited land, poor people have encroached into wetlands.
As of 2002, the dense mangrove swamp forest, which included luxuriant growths of palms, was undergoing extinction due to urbanization.
The houses and industrial buildings on the cleared land are poorly built, without adequate drainage.
Pools of stagnant water are breeding grounds for disease.
Human and industrial waste end up in the channels of the Wouri, reducing its rate of flow.
River floods and sea incursions may cause rises of water level from 2 metres (6.6 ft) to 5 metres (16.4 ft) within a few minutes, destroying buildings and washing raw sewage into the wells. Waterborne diseases such as typhus
Typhus
Epidemic typhus is a form of typhus so named because the disease often causes epidemics following wars and natural disasters...
and dysentery
Dysentery
Dysentery is an inflammatory disorder of the intestine, especially of the colon, that results in severe diarrhea containing mucus and/or blood in the faeces with fever and abdominal pain. If left untreated, dysentery can be fatal.There are differences between dysentery and normal bloody diarrhoea...
are common causes of death.
Fishery is economically of great importance to Cameroon, with about 40,000 tonnes caught each year, of which one third is exported.
In 1994, US$60 million worth of fish was exported to Europe, three quarters of which came from 12 industrial-scale fishing companies.
About 40% of the workforce in coastal Cameroon are full-time unregistered fishers.
Fish contributes about 44% of the protein in the local population's diet.
The mangroves of the estuary are spawning grounds for many types of commercial fish, but they are not protected.
The area covered by mangroves continues to shrink and the fish population has been declining steadily.
Levels of persistent organic pollutants in the fish are rising.
A 1991 study showed excessive levels of DDTs and PCBs in fish, shrimp and oysters in the area around Douala.
High pollution loads of heavy metals such as mercury, lead and cadmium are also a concern.
Oil potential
There appears to be potential for oil and gas production.The Matanda block in the northern half of the estuary and the surrounding region has estimated reserves of between 60 and 300 million barrels.
Exploratory work by Gulf Oil
Gulf Oil
Gulf Oil was a major global oil company from the 1900s to the 1980s. The eighth-largest American manufacturing company in 1941 and the ninth-largest in 1979, Gulf Oil was one of the so-called Seven Sisters oil companies...
several decades ago indicated that production of 4 million barrels a year could be feasible.
In April 2008, a subsidiary of Swiss
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
firm Glencore International AG and Afex Global Limited signed a deal with the Cameroon state oil company for a $38 million exploration project in the 1187 square kilometres (458.3 sq mi) zone, which was approved by Badel Ndanga Ndinga, Minister of Industries, Mines and Technological Development.
Cited sources
|url=http://ramsar.wetlands.org/Portals/15/CAMEROON.pdf|title=Cameroon
|work=Ramsar Wetlands
|accessdate=2011-02-24}}
|url=http://www.entrepreneurnewsonline.com/2008/04/glencore-afex-s.html
|date=April 11, 2008
|title=Glencore, Afex sign exploration deal with Cameroon
|work=The Entrepreneur
|accessdate=2011-02-27}}
|url=http://nlbif.eti.uva.nl/bis/lobsters.php?menuentry=soorten&id=73
|title=Callianassa turnerana
|first=Lipke B. |last=Holthuis |authorlink=Lipke Holthuis
|work=Netherlands Biodiversity Information Facility
|accessdate=2011-02-27}}
|url=http://www.waltersmunde.com/papers/PESTICIDEUSEINCAMEROON.pdf
|first=Walters |last=Munde
|title=Pesticide Use in Cameroon
|accessdate=2011-02-27}}