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Preface Annex 1
The main challenges facing the sustainable use of coastal and marine resources are the loss of natural habitat and biodiversity, and the consequent loss of any opportunity of exploitation of renewable living resources. Other concerns include the long-term effects of climatic change and sea-level rise, and the interruption of coastal processes such as sediment supply, beach dynamics, and degradation of water quality due to human activities in catchment and estuaries. There are difficulties in managing human activities impacting on the environment because of inadequate legislation and compliance, the lack of capacity for detection, and inadequate education and environmental awareness. All these factors are exacerbated by poverty and disease, and, in some countries, conflict and migration.
OVERVIEW OF RESOURCES
The coastal and marine areas, which extend along the 10 000 km of coastline from Angola on the Atlantic Ocean side to Tanzania on the Indian Ocean side and offshore to the limit of the EEZ, encompass diverse living and non-living resources. The west coast is characterized largely by desert conditions and sparse human populations, but with rain forest established towards the mouth of the Congo River. Its seas are influenced by the cold, northward flowing Benguela Current, with highly productive upwellings supporting industrial-scale fisheries. The east coast, under the influence of the East African Coast Current which flows northward along the coast of Tanzania and the warm, southward flowing Mozambique and Agulhas currents, is sub-tropical in South Africa, becoming tropical and wetter northwards. Marine diversity increases towards the warmer zones. Much of the hinterland drains to this coast through rivers including the Rufiji, Zambezi, Limpopo and Incomati. In Mozambique and Tanzania, there are extensive coral reefs and sea-grass beds, and mangrove forests, especially around the Rufiji and Zambezi deltas (Figure 1), which are largely protected by barrier beaches. Parts of the South African coast are heavily urbanized and have associated industrial development (Figure 2).
There is a rich coastal and marine biodiversity associated with the fringing and patch coral reefs and mangrove forests in Tanzania and Mozambique (Figure 1). Mangrove areas in those countries total 6 483 km² (Taylor and others 2003) while, in Tanzania, fringing reef platforms and patch reefs occur on over 80 per cent of the coast (UNEP-WCMC 2000). Coral communities also occur on the Maputoland Reef in KwaZulu Natal, South Africa (Obura and others 2004). Most reefs were severely affected by the coral bleaching event of 1998 and there was further mortality in 2002. Patchy infestation by COTS has also been reported (Obura and others 2004). The Agulhas Current LME has an enhancing effect on biodiversity which extends from Tanzania to well along the South African coast. The estuaries of Tanzania and Mozambique support penaeid prawn fisheries while, on the reef shores, artisanal and subsistence fishing are major activities. In Tanzania, areas of coastal forest with high levels of endemism occur over about 350 km² as fragments of a formerly extensive lowland forest (UNEP 2001). The west coast has no significant coral reef development, with only a few coral species reported from Angola (UNEP-WCMC 2000, Figure 1). Mangrove is confined to Angola where 1 100 km² are recorded. It is characterized by productive upwelling systems between Cape Agulhas in South Africa and southern Angola – the Benguela Current LME (Box 6). It has relatively low diversity but makes an important contribution to the total African, and global, fish catch, with epipelagic species including the South African pilchard and the Cape anchovy.
There are significant coastal and offshore hydrocarbon resources (EIA 2005). Angola has by far the majority of Southern Africa’s estimated crude reserves – 5.4 thousand million barrels, mostly located in deep water. Reserves of natural gas, also largely offshore, make up about 2.5 per cent of Africa’s total. Reserves have been discovered in Angola (1.6 x 1012 cubic feet); Mozambique (4.5 x 1012 cubic feet); Namibia (2.2 x 1012 cubic feet); South Africa (780 x 109 cubic feet) and Tanzania (800 x 109 cubic feet), where there are commercial reserves under production around the island of Songo-Songo (EIA 2005).
Diamond mining from coastal sand dunes and by dredging inshore seabed sediments is a major industry in Namibia and western South Africa. The minerals have been derived over time from the diamond-bearing volcanic rocks exposed in the catchment of the Gariep (formerly Orange) River. In coastal sediments on the Indian Ocean shores of South Africa and Mozambique, there are commercially viable titanium and zirconium minerals, also derived from the hinterland.
There are three coastal UNESCO World Heritage sites in South Africa (UNESCO 2005). The Greater St Lucia Wetland Park has critical habitats for species from marine, wetland and savannah environments, and has exceptional species diversity.
ENDOWMENTS AND OPPORTUNITIES
The combination of coastal attractions and unique wildlife presents a powerful resource for the long term if utilized with care. Nearly all of the coastline holds some sort of attraction. With careful management, the value of the assets underpinning such attractions can increase. Travel and tourism are already major foreign exchange earners in Southern Africa and much of the income is generated in coastal areas, providing substantial employment opportunities for women as well as men. In South Africa, travel and tourism in 2005 is expected to generate US$30.3 thousand million of economic activity (total demand), in Namibia, US$1 004.4 million and in Tanzania, US$1 858.4 million, accounting for 9.7 per cent of its GDP and 7.7 per cent of total employment (WTTC 2005).
The mangrove forests present opportunities for improving the livelihoods of coastal people and contributing to the alleviation of poverty (Taylor and others 2003). They are a rich source of fuel, building poles, and materials for boat making, and provide nectar for large populations of bees. With effective conservation and replanting programmes, perhaps supported by ecotourism, these resources could be harvested on a sustainable basis, maintaining supplies while preserving their important ecological functions.
Total marine fisheries production declined from 1 556 000 t in 1988 to 1 289 000 t in 2000, the contribution to the world total declining from 11.0 to 7.2 per cent (FAO 2002c). However, despite this trend some countries have increased their production (Figure 9). The overall declining trend is a continuation of that reported for the period 1972-97 (UNEP 2002a) and is part of the global trend (Pauly and others). Approximately half the finfish catch is taken by South Africa, and more than half the crustacean catch is taken by Mozambique, where catch value is dominated by the shallow-water penaeid prawns. Despite the declining trends in marine fish production, fishery commodity exports over the period 1988- 2000 rose in value from US$200 million to US$892 million, while imports declined from US$224 million to US$195 million (FAO 2004b). In South Africa, coastal goods-and-services in 1998 were estimated to be worth about US$29 000 million (Government of South Africa 1998) or 37 per cent of the GDP; this figure incorporated about US$175 million in terms of benefits to subsistence fishermen. The commercial fishery was worth about US$270 million and the recreational fishery US$200 million.
Combined freshwater and marine aquaculture production rose from 4 000 t in 1988 to 11 000 t in 2000 (FAO 2002c). The seaweed Eucheuma is cultivated, mainly by women, on intertidal platforms mainly in Zanzibar, Tanzania, with a production of 7 000 t in 2002 (Figure 9). Cultivation is slowly spreading to mainland Tanzania and Mozambique. Seaweed farming represents an opportunity for coastal villagers, and especially women, to improve their incomes.
Hydrocarbon resources are making an increasingly strong contribution to the economy. Over the last decade or so, the focus of oil and gas exploration has shifted offshore to the coastal waters, where there are now many successful production ventures (EIA 2005). Angola is the only significant oil producer. Overall, by early 2004, Angola’s production reached nearly 950 000 bbl/d and this is expected to double by early 2008, with new deep-water production sites. South Africa’s production is also from offshore fields which, by late 2003, yielded more than 60 000 bbl/d. Much of the gas associated with oil production is currently flared or reinjected. In Tanzania, production on the island of Songo-Songo is gathered from on and around the island and transported via a 225-km pipeline to Dar es Salaam where it provides fuel for electricity generation. Development and production present considerable local employment opportunities, though mostly for men.
The value of the alluvial diamond industry in Namibia and western South Africa was estimated at US$625 million in 1998 (Government of South Africa 1998).
CHALLENGES FACED IN REALIZING DEVELOPMENT
The environmental issues and threats relating to the realization of development opportunities are addressed within the framework of the Nairobi Convention (by Tanzania, Mozambique and South Africa) and the Abidjan Convention (by Angola, Namibia and South Africa). These MEAs focus on coordinated protection and enhancement of the marine environment and coastal zones. Land-based activities impacting the coastal and marine resources in the countries flanking the Indian Ocean are being addressed through the Nairobi Convention as part of the GEF-funded WIO-LaB project (WIO-LaB 2005).
The coastal environment is vulnerable and is being degraded by the current levels of development. Critical ecological functions are being undermined, including those provided by mangrove swamps, coral reefs, rivers and estuaries, which protect and stabilize coastlines, and provide sediments for beaches and nursery areas for fish and prawns. These changes, ironically brought about by development activity, are increasing the vulnerability of human populations, particularly those in low-lying coastal areas. Such vulnerability will be exacerbated by sea-level rise, storm surges and tsunamis.
Population growth, combined with migration to large coastal cities, will form one of the major challenges for physical planning and policy formation to protect coastal areas. On the eastern coasts, the population is growing at 5 to 6 per cent annually, due to births and migration from inland rural areas, and coastal poverty levels are high (Obura and others 2004). The traditional cultural and religious beliefs of the indigenous communities relating to the marine environment and its resources are being lost as population densities increase and people move in from other areas, thus diminishing a vital management resource.
In Tanzania and Mozambique, the degradation of the coral reef resources due to increasing population pressures and coral bleaching is one of the most important management issues (Obura 2004, Obura and others 2004). Bleaching has caused the decline of 30 per cent of the reefs, and the threats posed by a growing population are probably slowing their recovery. In Mozambique and southern Tanzania, there have been increased rates of reef erosion, due in part to the bio- erosion of dead coral tables and plates. A patchy but widespread increase in COTS infestation was recorded in 2003 and 2004 in Tanzania. Much of the damage to the reef ecosystems is coming from fisheries exploitation. Specific threats include excess harvesting (in part by migrant fishers), the use of destructive gears such as beach seines and gill nets, and bomb fishing that damages juvenile fish populations and vulnerable species. In Tanzania, by far the most destructive type of fishing is dynamiting, which has been practised since the 1960s (Wagner 2004). In the 1980s and 1990s, dynamite blasts reached epidemic rates. Recent management initiatives there have already had a significant positive impact on the coral reef environment (Wagner 2004). Resource users, particularly fishing communities, have been increasingly involved, enhancing their environmental awareness. Mangrove areas continue to be under threat from pollution and coastal development, notably aquaculture and the construction of salt pans. The overall rate of deforestation in Mozambique is estimated at 18 km² per year (Taylor and others 2003).
In South Africa, the once abundant, easily accessible, shallow sub-tidal invertebrate resources, such as the southern rock lobster and the abalone, have been reduced by heavy commercial and in part illegal exploitation. High prices obtainable for abalone in eastern Asia have exacerbated the pressure on this species and increased poaching. The shallow-water prawns of Mozambique have long been the targets of artisanal fisheries and a major tourist attraction in local restaurants (Box 8). With the possible exception of sea cucumbers in Mozambique, there are few, if any, other large invertebrate stocks which remain to be profitably exploited. In contrast to most western African countries, Namibia’s policy of fisheries management since independence has generated economic and social benefits to the country (Alder and Sumaila 2004).
Constraints to coastal aquaculture development include the lack of sheltered waters and the environmental degradation of coastal environments, such as mangrove forests. It should also be realized that aquaculture and mariculture are energy-consuming, rather than energy-producing, processes. While there might be employment opportunities, the products, whether they be mussels, prawns, abalone or fish, tend to be beyond the means of poor communities.
Mineral extraction from dunes and the seabed is controversial, given the environmental degradation to which it can lead. On the east coast of South Africa, the mitigation of these impacts constitutes a sub-industry. The exploitation of mineral resources is a comparatively short- term operation and one which needs to be carefully managed in order to mitigate any short- or long-term environmental impacts. There is also a need for responsible management in order to maximize the benefits to the people of the country and to allow investment of profits in longer-term sustainable developments. In Tanzania, the extraction of live coral for lime burning is a widespread activity which can have highly destructive effects on reef habitats (see Obura 2004).
Physical shoreline change, including coastal erosion, is another common issue, though its causes include natural forcing as well as human interventions and pressures. In Tanzania, shoreline change – accretion as well as erosion – impacts particularly on tourism infrastructure. Erosion has led to the demolition of beach hotels on low-lying beach plains at Kunduchi, near Dar es Salaam. Attempts have been made to stabilize shorelines by the installation of groynes (Kairu and Nyandwi 2000, UNEP/GPA 2004). It is anticipated that coastal erosion will increase with sea-level rise associated with global climate change (IPCC 2001).