What is a mangrove forest?
Mangrove forests are found in coastal intertidal zones at tropical and subtropical latitudes around the globe. There are 80 different species of mangrove trees and shrubs. Growing in a coastal intertidal zone means that these trees and shrubs must be able to accommodate the rise and fall of the daily tides. To do this, many species grow on “prop roots,” giving the trees the appearance that they are on stilts, which keep them raised out of the water.
Other species have “aerial roots,” which grow vertically out of the soil and are exposed to atmospheric oxygen. The oxygen-deprived soil of the mangrove forests would not be conducive growth if the roots did not have other ways to take in oxygen.
The dense network of roots, shrubs, and trees give mangrove forests great stability. They protect coastlines from erosion caused by storm surges, currents, waves, and tides. This protection extends to the animals and humans that live among mangrove forests. A study done on the impacts of a 1999 “super-cyclone” in India shows how villages protected by the mangroves experienced far fewer casualties than villages left unprotected against the extreme weather.
The Sundarbans mangrove forest spans approximately 10,000 km2 across the eastern Indian state West Bengal and the western Khulna Division of Bangladesh. It is the largest continuous tract of mangrove forest in the world, formed by sediment deposition from the Ganges River (originating from the Himalayas) about 7,000 years ago. The Sundarbans are home to 58 species of mammals, 55 species of reptiles and around 248 bird species, as well as a human population of 12 million in the greater Sundarbans region. Conservation efforts within the mangrove forest to keep the effects of environmental degradation at bay include the erection of the Sundarbans National Park and the Sajnekhali Wildlife Sanctuary on the Indian side and three wildlife sanctuaries on the Bangladesh side, Sundarbans West Sanctuary, Sundarbans South Sanctuary, and Sundarbans East Sanctuary. Areas on both sides are designated UNESCO Natural World Heritage Sites.
