- Title: [SW News] (UNEP) THE STATE OF THE ENVIRONMENT
- Posted by/on:[AMJ][Thursday, March 22, 2001]
  |
Next:
Atmosphere 
Previous:
Freshwater 
Contents  |
Chapter
Two: The State of the Environment - Africa
Marine
and coastal areas
Africa's coastal ecosystems and marine biodiversity contribute
significantly to the economies of many coastal countries, mainly
through fishing and tourism. For example, in Namibia the fisheries
sector contributes more than 35 per cent of GDP and employs more than
12 000 people (Namibia Foundation 1994). The marine fishing
industry makes an important contribution to the balance of trade in
countries such as Morocco, which had the highest average annual marine
catches on the continent at 844 000 tonnes in 1995 (FAO 1997c).
In Southern Africa, the annual marine fisheries catch was estimated as
1.25 million tonnes in 1995, with a potential sustainable catch of
2.7-3.0 million tonnes (FAO 1997c and SADC 1996). However, the
sub-region has experienced major changes in the composition and total
landings of fish. Once regarded as one of the richest fishing grounds
in the world, the catches on the west coast have declined sharply from
the 3 million tonnes harvested during the 1950s and 1960s (FAO 1993).
Coastal zones are also important for the tourists they attract and
the revenue they generate, particularly for countries such as Egypt,
Gambia, Kenya, Mauritius, Morocco, Seychelles, Tanzania and Tunisia.
Tourism is heavily dependent on the quality of the coastal
environment, and coastal zone degradation therefore has serious
implications for the industry. This is particularly true in small
island countries, such as Mauritius and Seychelles, that are
economically dependent on tourism. At the same time, the unmanaged
growth of the tourism industry can have a detrimental effect on the
coastal environment and resources (World Bank 1995a).
Coastal and marine resources have not been adequately assessed, and
are under increasing threat from development-related activities.
Habitat conversion and degradation, overexploitation, pollution and
sedimentation, coastal erosion, eutrophication, species introductions
and climate change are considered the major causes of marine
biodiversity loss (World Bank 1995b).
|
Marine
fish catch
|

(Click
image to enlarge)
Source:
compiled by UNEP GRID Geneva from FAO 1997c
|
|
| Total
marine fish catch grew by more than 50 per cent during
1975-90 but there was a downturn in Eastern Africa
after 1990. The catch in Southern Africa is far below
the 3 million tonnes of the 1950s |
|
Up to 38 per cent of the African coastline of 40 000 km is
considered to be under a high degree of threat from developments which
include cities, ports, road networks and pipelines, including 68 per
cent of marine protected areas (WRI, UNEP, UNDP and WB 1996, and World
Bank 1995a).
Urbanization of the coastal zone, particularly where it is poorly
controlled, is creating concern. It is projected that Western and
Central African coastal populations will double to 50 million in the
next 25 years, leading to a continuous chain of cities along the 1 000-km
Gulf of Guinea (World Bank 1995a) which will exceed the carrying
capacity of the coastal corridor. The expanding land and sea-based
activities along the Mediterranean coast of North Africa and in the
Red Sea over the past 20 years also pose increasing threats to coastal
ecosystems. Some 40-50 per cent of the Mediterranean population is
already concentrated along the coast, and this population is expected
to double by the year 2025 (UNEP 1996).
Marine pollution from major coastal cities is common and has even
reached toxic levels in some cases. In 1990 coastal cities and towns
in Southern Africa discharged more than 850 million litres of
industrial and human wastes into the sea daily through more than 80
pipelines, largely without any treatment (Cock and Koch 1991). In
1992, the lack of adequate infrastructure in Maputo caused significant
coastal sewage and pollution problems, while in Angola untreated
industrial waste pumped into the Bay of Luanda resulted in bacterial
contamination (IUCN 1992). There are no immediate prospects of
reducing the coastal pollution problems faced by many African
countries.
Africa's coastal ecosystems are also threatened by industrial
pollution, mining and oil exploration activities. Although the level
of industrial development in Africa is still relatively low, the rate
is accelerating along the coastal zone (World Bank 1995a). Most
industries still discharge their untreated wastes directly into rivers
and, ultimately, the oceans. The Mediterranean basin is now one of the
most polluted, semi-enclosed basins in the world. But pollution also
affects unenclosed seas. In 1993 industrial waste was found in the
coastal waters near major centres along the entire coastline,
stretching from Dar Es Salaam and Maputo on the east coast, to Durban
and Cape Town in South Africa, and to Walvis Bay in Namibia and Boa do
Cacuaco, 15 km north of Luanda in Angola (SARDC, IUCN AND SADC 1994).
In the Indian Ocean there are increasing risks of pollution from oil
spills because this is the main transportation artery for oil from the
Middle East to Europe and America, with an estimated 470 million
tonnes transported annually (Salm 1998). Similar risks apply in
Northern Africa as more than 100 million tonnes of oil are transported
through the Red Sea annually with insufficient maritime traffic
regulations (World Bank 1996a). Petrochemical complexes add to the
problem. For example, three major complexes at Annaba, Arzew and
Skikda in Algeria discharge large quantities of chromium, mercury,
oils, phenols, acids, chlorine and urea into the sea (World Bank
1995c). Similar situations exist in Egypt, Libya, Morocco and Tunisia.
In many areas, coastal erosion is a growing problem, driven by
natural processes which are exacerbated by the upstream construction
of dams and the development of other forms of coastal infrastructure
such as artificial lagoons and the clearing of mangrove systems. In
the longer term, climate change is also a major threat to critical
coastal ecosystems such as the Nile, the Niger and other low-lying
deltas and oceanic islands, particularly in the Indian Ocean, which
may be inundated by rising sea levels.
|
The
threat to coral reefs
|

(Click
image to enlarge)
Source:
WRI, ICLARM, WCMC and UNEP 1998
|
|
| Most
of Africa's coral reefs are found in the Indian Ocean,
where many are threatened by human activities |
|
Coral reefs are increasingly under threat from human activities
(see map), particularly from coastal development and overexploitation
as well as blast fishing and land-based pollution. The Indian Ocean
contains about 15 per cent of the world's mapped coral reefs, of which
more than one-half is estimated to be at risk from human activities.
Coral reefs in the northern Red Sea (in the Gulf of Aqaba and near the
Gulf of Suez) and along the coast of Djibouti are also considered to
be under a high degree of threat (WRI, ICLARM, WCMC and UNEP 1998).
Unprecedented coral bleaching following El Niño was reported in the
Indian Ocean during the first half of 1998, due to extremely high
ocean temperatures (noaa 1998). Such stress weakens corals and can
ultimately lead to their death (WRI, ICLARM, WCMC and UNEP 1998).
  |
Next:
Atmosphere 
Previous:
Freshwater 
Contents  |
[
News] |