Could you please proof read my work (Scientifically and correctgrammar) on mangroves issues regardingSocial, Economical, Environmental and Political areas. I wouldhighly appreciate your help.
Here itis:
Issues:
The mangrove forests provide at least US $1.6 billion each yearin ecosystem services as it acts as bases for successful fishingand prawning industry since it provides breeding, feeding andnursery areas for marine species worldwide. Studies in EasternAustralia have estimated that around 67% of the entire commercialcatch is composed of species dependent upon mangrove estuarineareas. The northern Prawn fishery, one of the most valuablefisheries in Australia which is lined by mangrove communities,injects millions of dollars each year into the NT economy. Forexample, In 1996/97 around 3266 tonnes of prawns were produced fromNT waters, valued at around $51 million. In addition, approximately$7.5 million of mud crab and $3.3 million of barramundi were caughtin the NT.
Also in countries such as Belize in USA, theannual economic benefits from reef and mangrove dependent fisheriesis estimated at between US$14–16 million. Furthermore, mangrovesalso benefit the economy by providing recreational facilities forexample, in 2007 many coastal Belizeans Coral reef- andmangrove-associated tourism contributed an estimated US$150 millionto $196 million to the national economy (12 percent to 15 percentof GDP).
Additionally, mangrove forests provide thesociety across the globe with huge range of 'ecological services'such as providing a source of timber which can be used to builddwellings and boats, fuel-wood for cooking and heating sinceAvicennia woods have a high calorific (heating) value,food and traditional medicines for example, the bark ofAvicennia marina can be used to treat stingray stings. Allof these mangrove products can raise the economy of the country bybeing sold by the individuals that collect them. For example, incountries such as Sri Lanka, the collective mangrove productsrepresent a total gross value of US$ 1,171/household/year. Theycontribute to the income of poor, medium and rich income categoryby approximately 42%, 37% and 21% respectively.
Mangroves are also food sources for thesurrounding ecosystems. In New South Wales, it was reported thatone square kilometre of mangrove forest contributes to about 600tonnes of plant material each year to the estuary food chain. Also,mangroves also provide birds sanctuary for northern hemispherebirds. For example, it was reported that a wide variety of 128 birdspecies have been found inhabiting mangroves in Darwin Harbour.
They also provide students with valuable sourcefor understanding the complex scientific interrelationshipsinvolved in the mangrove ecosystem for example linking the changesin abiotic factors with the changes in the biotic factors along themangroves intertidal zone.
Mangroves can also act as barriers againsttsunamis, cyclones and hurricanes. Empirical and field basedevidence is limited, but analytical models show that 30 trees per100m2 in a 100m wide belt may reduce tsunami flow rateby as much as 90%. For example in 1960 a tsunami hit the coast ofBangladesh in an area where the mangroves were intact. No-one died.These mangroves were subsequently cut down by the shrimp (prawn)farming industry and in 1991 thousands of people were killed when atsunami of the same magnitude hit the same region.
Mangroves create a physical barrier, slowingwater movement from the land and trapping sediments. Accordinglythey make land and reduce the erosion along estuaries and creeksand by doing so, they reduce contaminants and sediment run up intothe water and act as natural bio-filters, maintaining the health ofcoral reefs and coastal habitats.
Furthermore, the mangrove forests play animportant role in sequestering coastal carbon from the atmosphereand dissolving it into the ocean. Although the intertidal mangroveforests cover only 0.1% of the earth's surface, they contribute upto 10 % worldwide of the ocean's dissolved organic carbon. This isapproximately equal to the amount reaching the ocean from theAmazon river, the largest single source of dissolved organiccarbon.
Unlike CO2 absorbed directly from theatmosphere, much of the carbon produced by mangrove trees is boundup in large molecules which are highly resistant to decomposition,and is therefore likely to be held in the ocean for decades insteadof being returned to the atmosphere as carbon dioxide.
Due to the extractive activities in mangrove forests inAustralia such as the illegal collection of crabs and mangroves'fruits for medicinal purposes as well as timber harvesting, thegovernment and several agencies have introduced laws to protect themangorve forests. For example on the 1st of March 2009,in Queensland, the Government introduced green zones which protects16 % of the Moreton bay marine park. The Government has placed, a$21 million investment in the park which includes a $15 millionStructural Adjustment Program to reduce the environmental andeconomic effects of commercial fishing effort displaced by the newzoning arrangements by purchasing commercial fishing licences
Another example is that in 2003, 465 km2 ofmangroves and associated habitats around Darwin Harbourwere zoned conservation areas by several agencies, including EPA (Environmental protection Agency), DPI ( Department of planning andinfrastructure) and several others, under an amendment to theNorthern Territory Planning Scheme. This includes 95.6% ofmangroves in the harbour. Also, in South Australia, 28% of themangroves are lying within protected areas that are covered by anumber of acts set by the government
