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Reclaiming Wetlands














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Here we will tell more about Reclaiming Wetlands.
 
 
Wetlands refer to areas that are flooded for part of or all of the year with fresh or salt water.
 
Three examples of wetlands are swamps, marshes and bogs.








































Swamps

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The dominant vegetatiom in swamps is woody plants like trees and shrubs. A swamp is a shallow body of water in a low-lying poorly drained depression. Mangrove swamps are found along the coast and are subject to flooding by seawater.






Bogs

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Bogs are typically covered with moss. Bog waters are usually acidic.






Marshes

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Marshes are characterised by grasses and weeds. They are often found along ponds, rivers and stream edges in shallow water. Therefore they are often covered with freshwater.








































Wetlands can be reclaimed by draining the excess water.




How are the excess water being drained?

Firstly, before drainage can be carried out, dikes need to be built around the area being reclaimed to prevent more water from going in.
 
After which, the area can then be drained by pumping out the water, or constructing artificial channels called drainage canals.

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Drainage canals carry excess water away from the reclaimed area to a nearby river or sea.

What is done after the water is being drained from the area?

An area that has been drained is usually lower than the surrounding areas. Therefore it is necessary to replace the water withdrawn with fill material as it is prone to becoming filled with water again.
 
Sand and rocks are fill materials which are most conveniently obtained from nearby hills which are also levelled out in the process. Sand and gravel from the seabed can also be used as fill material. 

What problems are there by reclaiming wetlands?

Natural habitats are lost over the process as these wetlands provide habitats for wildlife.
 
A problem with severe flooding may be faced as the area being drained may get flooded with water again.

What can reclaimed wetlands be used for?

Reclaimed wetlands can be used for recreation, housing, industry and agriculture.
 
Some reclaimed wetlands are Tanjong Karang in Malaysia, and U.S.A in California.