For almost all plants, salt water is lethal, yet the red mangro flourishes in its twice daily submersion. The retreating tide reveals the key to the mangrove's survival. Its roots are covered by warty growths which surround pores that take in oxygen from the air when the roots are out of water.
When underwater, the pores allow water through, but ingeniously also work to filter out 99% of the salt on its way through. Any salt that does get past is pumped into a few sacrificial leaves that then turn yellow and are discarded.
Available since: Thu 3 Dec 2009
- David Attenborough
- Neil Lucas
- Executive Producer
- Michael Gunton