More than one in six mangrove species worldwide are in danger of extinction due to coastal development and other factors, including climate change, logging, and agriculture, according to the first-ever global assessment on the conservation status of mangroves for the IUCN Red List of Threatened Species.
Causes of depletion of mangroves
Clearing: Mangrove forests have often been seen as unproductive and smelly, and so cleared to make room for agricultural land, human settlements and infrastructure (such as harbors), and industrial areas.
Overharvesting: Mangrove trees are used for firewood, construction wood, wood chip and pulp production, charcoal production, and animal fodder.
River changes: Dams and irrigation reduce the amount of water reaching mangrove forests, changing the salinity level of water in the forest. If salinity becomes too high, the mangroves cannot survive. Destruction of coral reefs: Coral reefs provide the first barrier against currents and strong waves. When they are destroyed, the stronger-than-normal waves and currents reaching the coast can undermine the fine sediment in which the mangroves grow.
Climate change: Mangrove forests require stable sea levels for long-term survival. They are therefore extremely sensitive to current rising sea levels caused by global warming and climate change. Importance of mangroves in maintaining coastal ecology
Mangroves are vital to coastal communities as they protect them from damage caused by tsunami waves, erosion, and storms, and serve as a nursery for fish and other species that support coastal livelihoods. In addition, they have a staggering ability to sequester carbon from the atmosphere and serve as both a source and repository for nutrients and sediments for other inshore marine habitats, such as sea grass beds and coral reefs.