Geographical regions
Mangroves occur in numerous areas worldwide. See List of mangrove ecoregions.Africa There are important mangrove swamps in Kenya, Tanzania and Madagascar, with the latter even admixing at the coastal verge with dry deciduous forests. The delta of the Rufiji River is reportedly home to the largest mangrove forest in the world.[citation needed]
Nigeria has Africa's largest mangrove concentration, spanning 36,000 km2. Oil spills and leaks have destroyed many in the last fifty years, damaging the local fishing economy and water quality.
Along the coast of the Red Sea, both on the Egyptian side and in the Gulf of Aqaba, mangroves composed primarily of Avicennia marina and Rhyzophora mucronata in about 28 stands cover about 525 hectares.[citation needed] Almost all Egyption mangrove stands are now protected.
Americas
Mangroves live in many parts of the tropical and subtropical coastal zones of North, South and Central America.Continental United States
Because of their sensitivity to subfreezing temperatures, mangroves in the continental United States are limited to the Florida peninsula (see Florida mangroves) and isolated growths of black mangrove (Avicennia germinans) along the coast of southern Louisiana and south TexasCentral America and Caribbean
Mangroves occur on the west coast of Costa Rica, on the Pacific and Caribbean coasts of Nicaragua, Belize, Guatemala, Honduras, and Panama, and on many Caribbean Islands, such as Curaçao, Bonaire, Antigua, Anguilla, the Bahamas, Saint Kitts and Nevis and St. Lucia. Significant mangals include the Marismas Nacionales-San Blas mangroves in Mexico. Mangroves can also be found in Puerto Rico, Cuba, the Dominican Republic, Haiti, Jamaica, Trinidad, Barbados, and the Pacific coast of El Salvador.Belize
The nation of Belize boasts the highest overall percentage of forest cover of any of the Central American countries. In terms of Belize's mangrove cover - which assumes the form not only of mangrove 'forest' but also of scrubs and savannas, among others - a 2010 satellite-based study of Belize's mangroves by the World Wildlife Fund (WWF) and the Water Center for the Humid Tropics of Latin America and the Caribbean (CATHALAC) found that in 2010, mangroves covered some 184,548 acres (74,684 hectares) or 3.4% of Belize's territory. In 1980, by contrast, mangrove cover stood at 188,417 acres (76,250 hectares) - also 3.4% of Belize's territory, although based on the work of mangrove researcher Simon Zisman, it is estimated Belize's mangrove cover in 1980 represented 98.7% of the precolonial extent of those ecosystems. Belize's mangrove cover in 2010 was thus estimated to represent 96.7% of the precolonial cover.Assessing changes in Belize's mangrove cover over a 30-year period was possible because of Belize's participation in the Regional Visualization & Monitoring System (SERVIR, in Spanish) a regional observatory jointly implemented by CATHALAC, RCMRD, ICIMOD, NASA, USAID, and other partners.South America
Ecuador and Peru have significant areas of mangroves, mainly in the Gulf of Guayaquil-Tumbes mangroves.
Venezuela's northern Caribbean island, Margarita, possesses mangrove forests in the Parque Nacional la Restinga.
Colombia possesses large mangrove forests on both its Caribbean and Pacific coasts.
Asia
Indomalaya ecozone
Mangroves occur on Asia's south coast, throughout the Indian subcontinent, in all southeast Asian countries, and on islands in the Indian Ocean, Arabian Sea, Bay of Bengal, South China Sea and the Pacific.The mangal is particularly prevalent in the deltas of large Asian rivers. The Sundarbans is the largest mangrove forest in the world, located in the Ganges river delta in Bangladesh and West Bengal, India.
Major mangals live on the Andaman and Nicobar Islands and the Gulf of Kutch in Gujarat.
Other significant mangals include the Bhitarkanika Mangroves and Godavari-Krishna mangroves.
In Vietnam, mangrove forests grow along the southern coast, including two forests: the Can Gio Mangrove Forest biosphere reserve and the U Minh mangrove forest in the Sea and Coastal Region of Kien Giang, Ca Mau and Bac Lieu province.
The mangrove forests of Kompong Sammaki in Cambodia are of major ecological and cultural importance, as the human population relies heavily on the crabs and fish that live in the roots.
The three most important mangrove forests of Taiwan are: Tamsui River in Taipei, Jhonggang River in Miaoli and the Sihcao Wetlands in Tainan. According to research, there are four existing types of mangrove in Taiwan.[citation needed] Some places have been developed as scenic areas, such as the log raft routes in Sihcao.
In the Indonesian Archipelago, mangroves occur around much of Sumatra, Borneo, Sulawesi and the surrounding islands, while further north, they are found along the coast of the Malay Peninsula.
- A cluster of mangroves on the banks of the Vellikeel River in Kannur
- An old light house in the middle of mangroves on the banks of the Godavari River in Andhra Pradesh
- Mangroves in Mangalavanam Bird Sanctuary of Kerala
- A mangrove of the genus Sonneratia, showing abundant pneumatophores growing on the landward margin of the reef flat on Yap.
- The location and relative density of mangroves in Southeast Asia and Australasia.
Pakistan
Pakistani mangroves are located mainly along the Indus delta (the Indus River Delta-Arabian Sea mangroves ecoregion). Major mangrove forests are found on the coastline of the provinces of Sindh and Balochistan. In Karachi, land reclamation projects have led to the cutting down of mangrove forests for commercial and urban development.Middle East
Oman, near Muscat, supports large areas of mangroves, in particular at Shinas, Qurm Park and Mahout Island. In Arabic, mangrove trees are known as qurm, thus the mangrove area in Oman is known as Qurm Park. Mangroves are also present extensively in neighboring Yemen.Iranian mangrove forests occur between 25°11′N to 27°52′N. These forests exist in the north part of the Persian Gulf and Oman Sea, along three maritime provinces in the south of Iran. These provinces respectively from southwest to southeast of Iran, include Bushehr, Hormozgan and Sistan & Balouchestan.
Australia
Main article: Australian mangroves
More than fifty species of Rhizophoraceae grow in Australasia with particularly high biodiversity on the island of New Guinea and northern Australia.Australia has approximately 11,500 km2 of mangroves, primarily on the northern and eastern coasts of the continent, with occurrences as far south as Millers Landing in Wilsons Promontory, Victoria (38°54′S) and Barker Inlet in Adelaide, South Australia.
[edit] New Zealand
New Zealand also has mangrove forests extending to around 38°S (similar to Australia's southernmost mangrove incidence): the furthest geographical extent on the west coast is Raglan Harbour (37°48′S); on the east coast, Ohiwa Harbour (near Opotiki) is the furthest south mangroves are found (38°00′S).Pacific islands
Twenty-five species of mangrove are found on various Pacific islands, with extensive mangals on some islands. Mangals on Guam, Palau, Kosrae and Yap have been badly affected by development.Mangroves are not native to Hawaii, but the red mangrove, Rhizophora mangle, and Oriental mangrove, Bruguiera sexangula, have been introduced and are now naturalized. Both species are classified as pests by the University of Hawaii Botany Department.
Cultivating mangroves
Red mangroves are the most common choice for cultivation, used particularly in marine aquariums in a sump to reduce nitrates and other nutrients in the water. Mangroves also appear in home aquariums, and as ornamental plants, such as in Japan.The Manzanar Mangrove Initiative is an ongoing experiment in Arkiko, Eritrea, part of the Manzanar Project founded by Dr Gordon H. Sato, establishing new mangrove plantations on the coastal mudflats. Initial plantings failed, but observation of the areas where mangroves did survive by themselves led to the conclusion that nutrients in water flow from inland were important to the health of the mangroves. Trials with the Eritrean Ministry of Fisheries followed, and a planting system was designed to introducing the nitrogen, phosphorus, and iron missing from seawater. The propagules are planted inside a reused galvanized steel can with the bottom knocked out; a small piece of iron and a pierced plastic bag with fertilizer containing nitrogen and phosphorus are buried with the propagule. As at 2007, after six years of planting, there are 700,000 mangroves growing; providing stock feed for sheep and habitat for oysters, crabs, seashells and fish.
Exploitation and conservation
Approximately 35% of mangrove area was lost during the last several decades of the twentieth century (in countries for which sufficient data exist), which encompass about half of the area of mangroves. The United Nations Environment Program also estimated shrimp farming causes a quarter of the destruction of mangrove forests. Likewise, the 2010 update of the World Mangrove Atlas (WMA) indicated a fifth of the world's mangrove ecosystems have been lost since 1980.
Grassroots efforts to save mangroves from development are becoming more popular as the benefits of mangroves become more widely known. In the Bahamas, for example, active efforts to save mangroves are occurring on the islands of Bimini and Great Guana Cay. In Trinidad and Tobago as well, efforts are underway to protect a mangrove threatened by the construction of a steelmill and a port. In Thailand, community management has been effective in restoring damaged mangroves.
It has been cited that mangroves can help buffer against Tsunami, cyclones, and other storms. One village in Tamil Nadu was protected from tsunami destruction - the villagers in Naluvedapathy planted 80,244 saplings to get into the Guinness Book of World Records. This created a kilometre-wide belt of trees of various varieties. When the tsunami struck, much of the land around the village was flooded, but the village itself suffered minimal damage.
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