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| Muhando, C.A.; Mohammed, M.S.; Machano, H.. |
| Coral reefs play a crucial role in the well being of coastal communities in Tanzania (Johnstone et al., 1998; Muhando, 1999). However, despite their usefulness, coral reefs are being degraded by destructive anthropogenic activities (Salm et al., 1998) and natural causes (e.g., competition, predation, diseases, bleaching, etc.). The coral bleaching and mortality event of March - June 1998 was the most serious natural calamity ever recorded in the Indian Ocean (Wilkinson, et al., 1999). Several areas along the coast of Tanzania were affected. The degree of coral mortality varied between sites, from 60% - 90% at Tutia Reef in Mafia Island Marine Park and Misali Reef on the west coast of Pemba, to approximately 10% on reefs around Unguja Island, Zanzibar... |
| Tipo: Other |
Palavras-chave: Coral reefs. |
| Ano: 1999 |
URL: http://hdl.handle.net/1834/434 |
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| Muhando, C.A.; Mohammed, M.S.. |
| Surveys conducted in the 1980s and early 1990s indicated that coral reefs in Tanzania were being degraded by overexploitation and destructive resource harvesting practices, particularly dynamite fishing and the use of dragnets, with concomitant reduction in fish abundance. Despite reduction in dynamite fishing on most parts of the Tanzania coast, recent coral reef surveys (1999 and 2000) have indicated that live coral cover and the health of reef corals were further degraded by the 1998 coral bleaching event. The extent of coral mortality differed between areas and species. Although the relative contribution of some taxa such as acroporids and pocilloporids decreased on most reefs surveyed, there was no evidence of species extinction. Despite extensive... |
| Tipo: Journal Contribution |
Palavras-chave: Coral reefs Mortality causes Benthos Reef fish Bleaching Degradation ISW; Tanzania. |
| Ano: 2002 |
URL: http://hdl.handle.net/1834/25 |
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| Ngusaru, A.S.; Mohammed, M.S.. |
| The water and salt balance at Chwaka Bay in Zanzibar, Tanzania suggests that in order to balance the inflow and outflow of water, there must be a net flux of water from the bay to the open ocean during both the dry and wet seasons. The corresponding salt residual fluxes indicate advective salt export. However, exchange between the bay water with the open ocean replaces this exported salt via mixing. The freshwater residence times at Chwaka Bay are 24 days for dry and 37 days for wet season. The budgets for non-conservative materials indicate a net dissolved inorganic phosphorous (DIP) and dissolved inorganic nitrogen (DIN) flux from the bay to the ocean during wet season. The calculated DIPsyst and DINsyst suggest that the bay acts as a DIP and DIN source... |
| Tipo: Journal Contribution |
Palavras-chave: Water budget Salt budget Nutrient cycles ISW; Tanzania; Chwaka Bay. |
| Ano: 2002 |
URL: http://hdl.handle.net/1834/31 |
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