Mangroves
Mangroves are the characteristic littoral plant formation of tropical and subtropical sheltered coastlines with various limiting factors like lack of oxygen, high salinity and diurnal tidal inundation. They are basically evergreen land plants growing on sheltered shores, typically on tidal flats, deltas, estuaries, bays, creeks and the barrier islands.
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Mangroves are trees and bushes growing below the highwater level of spring tides which exhibits remarkable capacity for salt water tolerance (halophytes).
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The best locations are where abundant silt is brought down by rivers or on the backshore of accreting sandy beaches.
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They require high solar radiation and have the ability to absorb fresh water from saline/ brackish water.
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Mangroves exhibit Viviparity mode of reproduction i.e. seeds germinate in the tree itself (before falling to the ground). This is an adaptive mechanism to overcome the problem of germination in saline water.
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Leaves are thick and succulent with sunken stomata for limiting water loss and contain salt secreting glands.
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It produces pneumatophores (areal roots) to overcome respiration problem in the anaerobic soil conditions. Adventitious roots which emerged from the main trunk of a tree above ground level are called stilt roots.