Mangrove swamps are unique for their ability to withstand salt water with only occasional fresh water flushing. Mangrove seeds can withstand floating for days in salt water until they reach land to start a new swamp. This alone makes mangrove swamps valuable for shoreline protection in flood zones, where the root systems protect estuary and marine communities by blocking wave action that would tear out chunks of beach. Their roots trap and hold unstable soil and are habitat to filter feeders that clean water of sediment and nutrients which could cause algae blooms. These filter feeders are food for other fish, birds, and mammals that live among the roots and branches of mangrove swamps. People use these same roots as a platform for catching crabs, fish, and birds that feed among the roots. The leaves provide oxygen during photosynthesis. Their falling leaves build land up in areas where they grow. This building sediment eventually smothers inshore mangrove swamps, trapping the carbon they have stored, lowering the concentration of green house gases.
If storms increase in intensity, as predicted with forced climate change, mangrove swamps will play a critical role in protecting low lying shore lines with the people and animals living there. The unique adaptations of mangrove trees preserves a bank ofDNA for future needs such as food crops to withstand climate change, biological waxes, and plastics as petroleum supplies are depleted. Their scenic value brings in tourism and money to local economies.