Take The Path Less Ordinary

Staying above the waterline is mangrove tree’s forte

The mangrove swamps are vital for healthy coastal ecosystems. The forest detritus, consisting mainly of fallen leaves and branches from the mangroves, provides nutrients for the marine environment and supports immense varieties of sea life in intricate food webs associated directly through detritus or indirectly through the planktonic and epiphytic algal food chains. (Note: Plankton and benthic algae are primary sources of carbon in the mangrove ecosystem, in addition to detritus.)

Because of the rich biodiversity stock, mangrove forests are prime nesting and migratory sites for hundreds of bird species, making pit stops to feed for the winter. Additionally, manatees, crab-eating monkeys, fishing cats, monitor lizards, sea turtles, and mud-skipper fish also utilize the mangrove wetlands as habitat.

How did the term “mangrove” arise?

NO ONE really knows. It might be derived from some of the ancient names given to some mangrove trees: the Portuguese called them mangue, the Spanish mangle, the Malays manggi-manggi or mangin.

1. Refuge - Tree climbing crabs and sea snails climb up their aerial roots at high tide to avoid aquatic predators. The roots provide a surface for all kinds of creatures from algae to shellfish. And the tangle of roots provide hiding places for young fishes and shrimps from larger predators. Their branches provide shelter for creatures from Proboscis Monkeys and nesting sites for large herons, to crevices for insects and other tiny creatures.

2. Food - While on the tree, leaves are eaten by all kinds of creatures. Monkey snack on the shoots and leaves, small insects nibble on them. Fallen leaves are an important source of nutrients both within the mangrove habitat and when it is flushed out to the coral reefs. The leaves are rapidly broken up by crabs and other small creatures, and further broken down by micro-organisms into useful minerals. There are even tiny moth larvae that feed on pneumatophores.

3. Water Filter - Underwater, a huge number of filter-feeders are fastened on the tangle of roots: barnacles, sponges, shellfish. These filter feeders clean the water of nutrients and silt. As a result, clear water washes out into the sea, allowing the coral reef ecosystem to flourish.

4. Soil Stabiliser - Mangrove roots prevents mud and sand from being washed away with the tide and river currents. Mangrove trees also slowly regenerate the soil by penetrating and aerating it (other creatures such as crabs and mud lobsters also help in . As the mud builds up and soil conditions improve, other plants can take root. Mangrove trees also reduce the damage from violent storms.

Mangrove role for shoreline community

Mangrove ecosystems have traditionally been sustainably managed by local populations for the production of food, medicines, tannins, fuel wood, and construction materials. For thousands of coastal residents, mangrove forests offer dependable, basic livelihoods and sustain their traditional cultures.

Thanks to its crucial role as spawning and nursery ground for sealife, fishermen living in mangrove draped coastline are always blessed with bountiful catch.

The protective mangrove buffer zone helps minimize damage of property and losses of life from hurricanes and storms. In regions where these coastal fringe forests have been cleared, tremendous problems of erosion and siltation have arisen, and sometimes terrible losses to human life and property have occurred due to destructive storms.

Why don’t mangrove trees grow in freshwater swamp?

One reason could be that they are unable to grow as fast as other freshwater plants and are soon overwhelmed. They may also be unable to cope with the bacteria and fungi found in freshwater.

Only plants that can survive the harshest saline soil can thrive in the mangrove. One such champion is the Piai or mangrove fern. Its young shoots are salty and usually added into local cuisine for flavouring

How does mangrove trees survive in salty condition?

To deal with salt, all mangrove trees exclude some salt at the root level, and all can tolerate more salt in their tissues than “normal” plants, often in quantities that would kill other plants. But some have more effective ultra filtration at the root level to exclude more salt.

Any salt that gets through are believed to be stored in old leaves which are later shed. These include Bruguiera, Sonneratia and Rhizophora. A few can tolerate high levels of salt in their issues and their sap can be up to one-tenth as salty as sea water. They then secrete the excess salt through special cells on their leaves. Avicennia does this best and is often the only tree to survive is hot salty regions.

Mangrove Holly - This plant has no relation with the Christmas Holly although but it bears an uncanny resemblance. Because for its high saline content, locals store the leaves together with rice and other grains to act as desiccant (moisture remover). The plant also has the ability to expel salt crystals on its leaves which will be flushed off during rain

Although mangrove trees are adapted to grow in salt water, they require regular flushing with freshwater. They will die if immersed in saltwater all the time.

Root of the matter

Mangrove roots not only provide support in unstable soils and to withstand currents and storms, but also breathe air. To avoid suffocation in the oxygen poor mud, mangrove trees snorkel for air. They develop aerial or air-breathing roots. These take in above ground air. All aerial tree roots have on their surface, special tiny pores to take in air (lenticels). Only air can get through the lenticels, not water or salts.

Tough toddlers

If it’s hard for adult trees to cope with their environment, it’s even harder for tender seedlings which are usually dispersed by seawater. Thus many mangrove trees have special adaptations to give their offspring the best chance in their harsh habitat. Many provide their seedlings with a good store of food and floatation devices.

The bakau minyak will only releases its spear seeds onto the muddy soil during low tide

In some, the fruit does not fall away when it ripens. Instead, the seed within the fruit starts to germinate while it is still on the mother tree, and the mother tree channels nutrients to the growing seedling (vivipary).

Water everywhere, but not a drop to drink

Freshwater is as precious to a mangrove tree as to a desert plant. They have to expend energy to get rid of the salt in every drop of water they use.

Thus mangroves have many water conserving features of desert plants. To minimise water loss through evaporation they may have thick waxy leaves, hairy leaves (to trap an insulating layer of air near the leaf). They may also store water in succulent leaves. Mangroves also protect their hard won parts with spiny leaves (e.g., Sea Holly) or waxy leaves; and high levels of tannins and other toxins (e.g., Blind Your Eye). Mangrove plants are thus a precious resource of chemicals that have myriad potential uses for humans.

More good read …

1. Fireflies - Mangrove’s nightlife takes on a new meaning
2. If you are keen to experience the beauty of untouched mangrove forest with our expert, look up this day trip