The environment of Eastern Africa

What's at risk
Threats
– Pollution
– Desertification
– Coastal degradation and erosion
– Climate change
The human factor

References

What's at risk

The Eastern African region covers four coastal countries along the East African coast (Kenya, Mozambique, Tanzania and Somalia), one large island state (Madagascar), three smaller archipelagic states (Comores, Mauritius and Seychelles), and the territories of France in the southwest Indian Ocean (La Réunion).

The environment here defies generalization, and encompasses several biogeographic provinces. Ecotypes include coastal dry forestss, coastal dunes, coastal floodplains, fresh and brackish water marshes,mangvoe forests, coral reefs, reef-back lagoons, sandy beaches and seabird rookeries (sea cliffs and nearshore islands). These areas function as essential habitat for local species including fish and migratory birds, as shoreline stabilizers, and as buffers again coastal erosion.

The coast of Eastern Africa is bathed by the great current systems of the Indian Ocean, which vary greatly with the seasonal monsoons. The Indian Ocean has particularly narrow continental shelves along this coast, and thus lower biological productivity than many coastal regions.

The coast is rich in varieties and numbers of marine life forms, however. Extensive and highly diverse coral reefs fringe its narrow shelves shores. Species-rich mangroves with their commercially important oysters, crabs and mullet abound near river estuaries and along the coasts, particularly those of Mozambique, Tanzania, Kenya and southern Somalia.

The region's people are dependent to a significant extent on coastal resources. Fisheries rely on the trawlable inter-reef areas and the species-rich mangroves with their commercially important oysters, crabs and mullet. Coastal ecosystems are important economically for tourism and recreation.

Threats

In 1981 a UNEP fact-finding mission to East Africa identified large-scale erosion, oil pollution, damaged coral reefs, ruined mangrove swamps, pollution from fertilizers and threats to precious marine animals as the major environmental problems in the region.

The list of threats to the environment has changed little since then. A workshop in 1997 listed domestic sewage, solid domestic waste, habitat degradation, agrochemical pollution and industrial waste pollution. The region remains characterized by vulnerable economies, large populations with a high rate of population growth, and areas subject to environmental stress.

Pollution

The important and heavily fished reef zone close to shore is particularly vulnerable to pollution and silting. Oil is a major pollution threat to coastal ecosystems, owing to the heavy use of the tanker route along the East African coast. On any given day there are hundreds of tankers in the Region, many of them Very Large Crude Carriers (VLCCs). Slicks are brought in from spills in the open ocean by coastal currents, while operational discharges from ships and refineries add to the load.

In recent decades, the growth of industry has brought an increasing volume of effluents to coastal waters. The use of agricultural chemicals has continued to grow, and sewage treatment continues to be inadequate in many parts of the region.

Some species of marine animals are already endangered as a result of human activities, particularly the dugong or manatee, which is often caught in fishing nets and drowned. Marine turtles continue to decrease in numbers as their eggs are poached and the adults are killed for their meat and decorative shells.

Eastern Africa is also undergoing an extraordinary rate of urbanization. As the cities have become overcrowded, water supplies have proven insufficient, and systems for drainage, sewerage and refuse disposal inadequate. Domestic sewage is discharged directly into rivers and in some cases the sea.

Although industrialization remains slow relative to other parts of the world, it takes place without proper environmental impact assessments legislative controls, leading to further pressure on the environment. Rivers, creeks and the sea have become dumping sites for industrial wastes. Industries of major environmental concern in the region include textiles, tanneries, paper and pulp mills, breweries, chemical factories, cement factories, sugar factories, fertilizer factories, and oil refineries. In some countries, slaughter houses near the sea are a serious source of marine pollution.

Desertification

Long drawn out droughts, over-grazing and poor agricultural practices, deforestation and reclamation of wetlands for agriculture are all combining to bring about desertification in the coastal areas of East Africa.

The continued high population growth rate is placing pressure on land beyond its carrying capacity, and driving out the traditional nomadic practices which allowed for environmental recovery. Livestock development is seldom accompanied by proper pasture management, leading to desert conditions in areas of concentration.

When these destructive pressures occur in semi-arid areas with shallow soils, desertification and desert encroachment can becomes irreversible. The semi-arid parts of Eastern Africa are particularly vulnerable.

Coastal degradation and erosion

Human encroachment and activities such as animal husbandry and agriculture are rapidly degrading the coastal environment of Eastern Africa, resulting in deforestation, destruction of mangroves and disappearance of other vegetation; a decline in soil fertility, and the death of wildlife. Marine resources are directly threatened by these activities.

Mangroves were once common in sheltered bays and estuaries, providing shelter to many important fish species and prawns. They are now threatened by intensive cropping to provide firewood, poles, tannin, medicinal products, paper pulp and timber, and to open up new space for aquaculture and salt production. Mangrove swamps are also threatened by fluctuations in the amount of fresh water and sediment reaching them caused by upstream hydraulic works, and indirectly by destruction of protective reefs.poles, firewood and by large-scale clearing for salt production.

Coral reefs have been damaged by excessive siltation resulting from poor agricultural practices, deforestation along riverbanks, and the dredging and and dumping associated with harbour development. Many were damaged by fishing with dynamite and poison, especially before these methods were outlawed in part of the region. Tourists collect coral as souvenirs. More recently the bleaching of corals has become a severe problem.

The shoreline in most of the region is receding as a result of coastal erosion: the shoreline retreat over parts of Tanzania has been estimated at between three and five metres per day. Barrier islands are particularly vulnerable to rising sea levels.

Climate change

A task team report on the implications of climate change for the Eastern African region (see UNEP: Potential impacts of expected climate change on coastal and near-shore environment. UNEP Regional Seas Reports and Studies No.140 (UNEP, 1992.) concluded that the region's low-lying coastal areas and marine ecosystems, water resources, terrestrial ecosystems and human settlements and coastal infrastructure are at risk as a consequence of climate change impacts.

The economies of the region are dominated by agriculture. Fishing is an important source of food and contributes to the economy of the majority of the countries. Tourism is an important activity.

The effects of climate change will be felt everywhere, perhaps most obviously in altered patterns of rainfall, coastal weathering, atmospheric pressure and evaporation. The spatial and temporal distribution of storms and cyclones will change their paths and frequency, and could well increase in intensity: Some scientists believe the terrible floods of early 2000 in Mozambique are but a taste of worse to come.

Besides the direct toll on human lives, there will be impacts on coastal habitats such as coral reefs, lagoons, and mangroves. The reefs will be vulnerable to wave action and sea-level rise as well as sedimentation. Their destruction will lead to a decline in natural coastal defences and further encourage coastal erosion.

The quality and quantity of water available from rainfall, rivers and ground water will be affected by changes in the distribution and amount of rainfall, evapo-transpiration, surface runoff, river discharge, recharge, and aquifer volumes. Drier and hotter conditions would place an inordinate pressure on water resources.

Ecosystem effects could include latitudinal and altitudinal shifts in plant and animal species as well as, loss of biodiversity due to water scarcity and arid soil conditions. While agriculture might benefit somewhat from a global increase in CO2, moisture deficits would lower crop yields and require additional irrigation. Sea-level rise would increase the intrusion of saline water up river mouths and also decrease the area available for cultivation on low-lying coastal areas and river estuaries.

Fisheries would be affected by changes to the breeding and migratory habits of most fish, hence, year to year variability of stocks could increase leading to a planning and management problems. Socio-economic activities, and infrastructure such as port facilities, waste disposal, roads, are already under stress. Climate change would create additional stress, hence reducing economic performance and growth.

The human factor

A critical problem in the region is the rapid rate of human population growth in some countries. Infrastructure has a hard time keeping up, with resulting strain on educational facilities as well as resources.

Much of the population resides in the coastal areas, employed by the light industry located along the coast and others in the tourist industry. Most of the region's economies rely on agriculture and tourism which together contribute close to 50% of the gross domestic product. Tourism specifically is a main earner of foreign exchange in the coastal parts of most of the countries in the region.

The population is unevenly distributed over the region. Northern Mozambique and Merca northwards of Somalia are almost uninhabited due to extreme climate conditions.

Both mainland and island populations are concentrated on the coasts, where population growth is higher than average for the region as a whole, largely owing to migration, urbanization and favourable employment opportunities. The majority of these populations are employed by the light industry located along the coast and others in the tourist industry. Most of the economies rely on agriculture and tourism which together contribute close to 50% of the gross domestic product. Tourism specifically is a main earner of foreign exchange in the coastal parts of most of the countries in the region.

The extremely rapid rate of population growth in some of the countries in the region is a critical factor, and the resulting pressure on social amenities, notably in the coastal cities, has become very high. The infrastructure is unable to keep pace with the population growth rate; educational facilities are no longer adequate and the resource base to support the required expansion programme meagre. There is great disparity in per capita income in the countries of the region for a variety of political and environmental reasons.

References (by date):

A Strategy for the Seas. UNEP, 1983. Text available.
Environmental problems of the East African region. UNEP Regional Seas Reports and Studies No. 12. (UNEP, 1982). This summary of results of the 1981 expert mission to Eastern Africa is available from the online bookstore, Earthprint. Earthprint website.
UNEP-sponsored programme for the protection of oceans and coastal areas. UNEP Regional Seas Reports and Studies No. 135. UNEP, 1991. Text available.
Potential Impacts of Expected Climate Change on Coastal and Near-Shore Environment. UNEP Regional Seas Reports and Studies No. 140 (UNEP 1992).
Implications of Expected Climate Change in the Eastern African Coastal Region: An Overview. UNEP Regional Seas Reports and Studies No. 149 (UNEP 1992). Text available.
Overview of Land-Based Sources and Activities Affecting the Marine, Coastal and Associated Freshwater Environment in the Eastern African Region. UNEP Regional Seas Reports and Studies No. 167. UNEP/ Institute of Marine Sciences, University of Dar es Salaam/FAO/SIDA (UNEP, 1998).

Other reading

Marine and coastal area development in the East African region. UNEP Regional Seas Reports and Studies No. 6. UN/UNESCO/UNEP (UNEP, 1982).
Industrial sources of marine and coastal pollution in the East African region. UNEP Regional Seas Reports and Studies No. 7. UNIDO/UNEP (UNEP, 1982).
Marine pollution in the East African region. UNEP Regional Seas Reports and Studies No. 8. FAO/UNEP (UNEP, 1982).
Public health problems in the coastal zone of the East African region. UNEP Regional Seas Reports and Studies No. 9. WHO/UNEP (UNEP, 1982).
Oil pollution control in the East African region. UNEP Regional Seas Reports and Studies No, 10. IMO/UNEP (UNEP, 1982).
Conservation of coastal and marine ecosystems and living resources of the East African region. UNEP Regional Seas Reports and Studies No, 11. IUCN/UNEP (UNEP, 1982).
Legal aspects of protecting and managing the marine and coastal environment of the East African region. UNEP Regional Seas Report and Studies No. 38. FAO/UNEP (UNEP, 1983).
Marine and coastal conservation in the East African region. UNEP Regional Seas Reports and Studies No. 39. IUCN/UNEP (UNEP, 1984).
Socio-economic activities that may have an impact on the marine and coast environment of the East African region. UNEP Regional Seas Report and Studies No. 41. (UNEP, 1984).
Legal aspects of protecting and managing the marine and coastal environment of the East African region: national reports. UNEP Regional Seas and Studies No. 49. FAO/UNEP (UNEP, 1984).
Marine and coastal conservation in the East African region: National Reports. UNEP Regional seas Reports and Studies No. 50. IUCN/UNEP (UNEP, 1984).
Socio-economic activities that may have an impact on the marine and coastal environment of the East African region: National reports. UNEP Regional Seas Reports and Studies No. 51. (UNEP, 1984).
UNEP Regional Seas Programme: the Eastern African experience. UNEP Regional Seas Reports and Studies No.53. (UNEP, 1984).
Oil spills and shoreline clean-up on the coasts of the Eastern African region. UNEP Regional Seas Reports and Studies No.57. IMO/UNEP (UNEP, 1985).
Action Plan for the protection, management and development of the marine and coastal environment of the Eastern African region. UNEP Regional Seas Reports and Studies No. 61. (UNEP, 1985).
Management and conservation of renewable marine resources in the Eastern African region. UNEP Regional Seas Reports and Studies No.66. IUCN/UNEP (UNEP, 1985).
A coast in common: an introduction to the Eastern African Action Plan. (UNEP, 1989).
I.Bryceson et al.: State of the marine environment in the Eastern African region. UNEP Regional Seas Reports and Studies No.113. (UNEP, 1990).
M.S. Iqbal: Assessment of the Implementation of the Eastern African Action Plan and the Effectiveness of Its Legal Instruments. UNEP Regional Seas Reports and Studies No. 150. (UNEP, 1990)
The mangrove of the Eastern African Region. ISBN 92-807-1348-5. (UNEP, 1992).
The International Coral Reef Initiative (ICRI) Western Indian Ocean and Eastern African Regional Workshop Report. UNEP/IUCN. (UNEP 1997).
Overview of Land-Based Sources and Activities Affecting the Marine, Coastal and Associated Freshwater Environment in the Eastern African Region. UNEP Regional Seas Reports and Studies No.167. UNEP/Institute of Marine Sciences, University of Dar es Salaam/FAO/SIDA. (UNEP, 1998).

Many of these publications are available from Earthprint's online bookstore.
To see on this site which are held in stock, consult the SMI list.
For a list of publications available in the Regional Coordinating Unit for the Eastern African region, consult the EAF library.