Mangroves are plants that live in one of the most difficult environments called the intertidal zone. The intertidal zone is the area of the coast, estuaries and rives where the sea moves in and out with the tides. The tides are caused by the gravitational pull of the moon and sun. The gravitation of the moon has a greatest effect on tides. Winds, storms, waves and seasons plus how the moon and sun line up against each other affects how high and low the tides move twice each day.
Mangroves mostly live on shallow mudflats. The roots of the mangroves help to collect the mud and prevent it from being washed away with the tides and storms. Where the tide moves up rivers, mangroves can line the river banks.
In some coastal locations mangroves can be kilometres deep before reaching dry land.