Jamaica
Vierros, M. (2000). Jamaica, in: Sheppard, C.R.C. (Ed.) Seas at the millennium: an environmental evaluation: 1. Regional chapters: Europe, The Americas and West Africa. pp. 559-574
In: Sheppard, C.R.C. (Ed.) (2000). Seas at the millennium: an environmental evaluation: 1. Regional chapters: Europe, The Americas and West Africa. Pergamon: Amsterdam. ISBN 0-08-043207-7. XXI, 934 pp., meer
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Beschikbaar in | Auteur |
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Documenttype: Revisie
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Abstract |
Jamaica has a rich natural heritage, with a range of habitats and plant and animal species. The 795 km long coastline is highly irregular, with diverse ecosystems, including bays, beaches, rocky shores, estuaries, wetlands, cays, seagrass beds and coral reefs. Jamaica's shallow-water marine ecosystems suffer from a number of impacts, including severe overfishing, industrial and domestic pollution and sedimentation, much of which has its origins in the pressures caused by a fast-growing population. These impacts are perhaps most clearly illustrated in the deterioration of Jamaica's coral reefs, caused by a combination of human and natural disturbances, including over-fishing of herbivorous fish, nutrient enrichment of the water, and a die-off of the grazing urchin Diadema. Long-term studies document a phase shift from a system dominated by corals to one dominated by fleshy macroalgae. Hillsides in the coastal watershed are subjected to forest clearance, estimated to be occurring at a rate of 10,000 hectares per year, leading to run-off and the removal of 80 million tons of topsoil yearly from farms and forests around the country. In addition, coastal mangrove areas, wetlands and seagrass beds are being destroyed by development, as developers continue to show preference for coastal areas, especially along the island's North Coast. Seagrass beds are affected by dredging and filling for the construction of ports, buildings, large water-front industries, water channels, and roads. This has resulted in the destruction of large tracts of seagrasses in the vicinity of major ports and harbours. There is appreciable drift of the population to urban areas, and some urbanised areas, especially around the capital, are affected by a wide range of domestic and industrial pollutants. Natural environmental variables causing marked effects include hurricanes which have had marked impacts on the coastal and shallow marine habitats, but there is also probably an impact from groundwater which is naturally nutrient enriched. Jamaica's waters are severely overfished with a record number of 240,000 people reportedly earning a living from the island's 795 kilometres of coastline. Overfishing on the narrow coastal shelf became apparent as early as the 1960s, and today the local fishery supplies only a third of local demand. Environmental conservation has been strengthened by legislation, such as the Natural Resources Conservation Act of 1994, and by increasingly active NGOs. |
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