Mangrove is the name for a tree—and also for a complex ecosystem—that bridges land and sea. There are around 70 species of mangrove trees (meaning trees that can grow in salty water and soils), but they are not all closely related. The ability to live in a swampy, salty habitat evolved many times over millions of years resulting in a wide diversity of mangrove trees.
What do they have in common? Mangrove trees have unique adaptations to survive salt water, and their roots provide structure and habitat for organisms to grow upon and hide behind. With plentiful tiny food, mangroves are important nurseries for fish we like to eat. Up in their branches, unique tropical organisms thrive, some able to bridge the land-sea gap and others that never enter the sea. And once they die, mangrove leaves and branches are broken down and eaten by another set of organisms, many of them microscopic.
These ecosystems not only provide homes to many species, they also take carbon dioxide from the atmosphere and store it, helping to reduce global warming and ocean acidification. Their numerous sturdy trunks protect coastal cities and towns from flooding during storms. It is estimated that a single hectare of mangrove can be worth $20,000 a year (or $8,100 per acre) in contributions to fisheries and coastal protection. Learn more about mangrove ecosystems.