Mangrove swamps are mostly found in the tropical and subtropical region where fresh-water meets salt water.
They have muddy soft soil and are a hostile environment for normal plants. This is because the soil has very low levels of oxygen and a high concentration of salt.
In addition, mangrove swamps are exposed to high intensities of sunlight and strong winds.
The pioneer species of a mangrove swamp are the Sonneratia sp. and Avicennia sp.
The presence of this species gradually changes the physical environment of the habitat.
The extensive root systems of these plants trap and collect sediments, including organic matter from decaying plant parts.
As time passes, the soil becomes more compact and firm. This condition favours the growth of Rhizophora sp. Gradually the Rhizophora sp. replaces the pioneer species.
The prop root system of the Rhizophora sp. traps silt and mud, creating a firmer soil structure over time.
The ground becomes higher. As a result, the soil is drier because it is less submerged by sea water.
The condition now becomes more suitable for the Bruguiera sp., which replaces the Rhizophora sp.
The buttress root system of the Bruguiera sp. forms loops which extend from the soil to trap more silt and mud.
As more sediments are deposited, the shore extends further to the sea. The old shore is now further away from the sea and is like terresterial ground.
Over time, terrestrial plants like nipah palm and Pandanus sp. begin to replace the Bruguiera sp.