Friday, 21 September 2007

Mangrove and Us

Marine Corner
(Lasallian Short Article, De La Salle University)

Mangrove & Us

What is mangrove? Mangrove is large tropical evergreen tree, genus Rhizophora, Avicennia, Bruguiera, that grows on muddy tidal flats and along protected ocean shorelines.These curious plants are salt tolerant and prosper where most other plants cannot live. They cover about 75 percent of tropical and subtropical shorelines worldwide. Kinds of mangrove are the red mangrove is usually closest to the water and is readily identified by its reddish prop roots, the black mangrove, which may be mingled with the red or a little behind it, has cable like roots and numerous breathing tubes (pneumatophores) that are exposed at low tide and the white mangrove with its grey-white trunk and flattened oval leaves is still higher on the slope. All three make use of breathing tubes or pores to draw oxygen into the root system, where being little oxygen available in the mucky soils where mangroves often grow.

What is mangrove function? The basic source of food here is litter fall, mostly leaves that the mangroves shed and replace all year long, plus bark, twigs, root material, guano from birds roosting in the trees, and organic matter of all kinds including dead animals and loose sea grass trapped in the maze of roots. All decompose to begin the food chain. Again, the agents are bacteria and fungi that produce edible detritus and are themselves eaten by marine animals often too small to see. They in turn are eaten by larger animals. And finally, larger predators, including humans, come along to harvest the bounty. For example, amphipods, fiddler crabs, killifish and minnows live in mangroves and eat detritus. They can withstand wide variations in temperature and salinity, and they are found almost everywhere. Another example, lobster larvae floating in the plankton, migrate to the roots of red mangroves. They consume both plant and animal material. The sea trout’s (from the croaker family) tolerate higher turbidity and feed on fish in mangroves and sea grass beds. As many marine animals migrate from one habitat to another, the mangrove forests, the sea grass beds and the coral reefs are interrelated and the health of one affects the others. Why we have to look for? Because this is prime habitats to the marine environment and influence for human.
By : Stella Kaunang