Before 1975, the world's largest
mangal resources were found in Indonesia. In Kalimantan alone, nearly half
of 1.8 million hectares of mangal were cleared between 1975 and 1994. In
Sulawesi, 110,000 hectares in 1965 were reduced to 30,000 hectares by
1994. In the Phillipines, mangal areas were reduced from 400,000 hectares
in 1920 to 140,000 hectares by 1994. And finally, from 1950 to 1983,
400,000 hectares of mangroves on the Vietnamese coast was reduced to 250,000.
Features of increasing pressure on mangrove coasts
Increasing human population in the coastal zone
Loss of mangrove forest
Increased coastal erosion
Increased impact from storms
Reduction in biodiversity
Decreased fisheries production
Decreased aquaculture pond production (in the long term)
Potentially non sustainable exploitation of Mangroves
Wood and other direct uses - Aquaculture and agriculture Salt ponds - Palm and sugar cane plantations Mining - Industrial and urban development - pollution Water abstraction - Pollution Mangrove forests can be heavily exploited as a source of wood and for other uses (e.g. industrial clearance of mangrove for wood chips to supply the rayon industry) If tree cutting is not properly managed, the typical results are reduction in tree size and species diversity. Primary forest, dominated by large trees of 3-4 species of Rhizophora, Brugeria, Kandelia and Avicennia can be reduced to secondary forest of trees less than 5m high or even to mangrove scrub of 1 or 2 species, and only 1-2m high. In extreme cases, mangroves are completely cleared, leaving easily eroded mud flats. Potentially sustainable (renewable) uses of mangrovesFisheries - Small-scale fishing/collecting of crabs, shrimps, fish and molluscs. Nursery for commercial fish and shellfish.Aquaculture - Integrated shrimp-cum-mangrove culture systems, crab culture, stock enhancement. Wood - Firewood, charcoal, paper products, construction timber, wood chips, furniture. Textiles - Synthetic fibres, dyes, tannins for leather Fishing - Fish poisons, tannins for net preservation, poles for traps Drugs - Pharmaceuticals Food - Sugar, cooking oil, vinegar, honey, animal fodder. Alcohol - Industrial alcohol fermented from sugar Coastal management - Shoreline and riverbank protection Recreation - Eco-tourism This site contains links to other internet sites. These links are not endorsements of any products or services in such sites, and no information in such site has been endorsed or approved by the website creator |
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Mangroves > Mangrove Reproduction >
Declining Mangroves |