Objavljeno: 05 Avg 2008 13:50 Naslov sporočila:
Have you visited Ras Mohamed Park yet? Were you also told not to miss the
Mangroves? Well, my first visit, on the southern tip of the park, was quite honestly rather a disappointment. Perhaps I was not well informed, but I had imagined something like a forest in the middle of the desert.
Your expectations generally aren't fulfilled when you take a trip to the mangroves, however, the trees with their roots coming out of the water are quite amazing when you find out more about them - not to mention the fact that plants do not usually grow in salty water.
Mangroves (generally) are trees and shrubs that grow in saline coastal habitats in the tropics and subtropics
the most northerly being in the Nabq protected area which is just a bit further up the coast of Sinai. This is truly the pushing the edge of its range to its extreme.
Taking a closer look at the mangrove at Ras Mohamed , we see that they are an evergreen shrub where trees are from 1 to 5 meters in length with a 40cm average diameter for the trunk. This makes them considerably shorter than Mangroves found further south along the Red Sea where heights reach from 5 to 7 meters. These trees have dense foliage with shiny green, thick ovate leaves as well as some small white to yellowish four petalled flowers. They also have hairy, ball-like petioles at the end of twigs. However the most significant feature of this tree is its protruding and bulging, over ground roots. These aerial roots, also known as pneumatophores help transport oxygen and filter water to the submerged roots which are found in the anoxic, water-logged soil . Logically these pneumatophores are generally taller and larger the closer the tree is to the sea. It is with these peculiar roots that the black mangrove in Ras Mohamed has adapted rather well to this extremely harsh environment.
Where other mangroves would not survive because of the high salinity and extreme drop in temperature during winter nights, the Avicennia marina in Ras Mohamed is flourishing and has a successful rate of natural reproduction, although tree density decreases somewhat nearer to the sea. Growing on hard-bottomed substrates these resilient trees are the only species that have made use of the muddy swamps-between the high and medium tide lines- created by the occasional flooding which brings water and soil down the wadis and into the sea. It is this freshwater from flash floods and ground water that allows the trees to grow in this saline environment.
What is also unique is that the mangrove forest at Ras Mohamed is an intensive source of life and a genuine sanctuary for it as well. Furthermore, As strange as this might sound, this mangrove forest is an integral part of the reef ecosystem. Not only does it provide sanctuary, a breeding area, and food for the migrating birds, it also provides the same service for juvenile fish which can be found sheltering between its shallow water aerial roots and feeding on its fallen leaves. Being quite productive in terms of foliage, the leaves that fall from trees also attracts many ghost crabs and other invertebrates which recycle the nutrients in the system. These crabs provide food for other larger predators and the billions of eggs they produce contribute substantially in enriching the sea waters around it with nutrients. Now, how is that for helping out with the sustenance of life on the reef !
However it is not only the crabs that benefit from its leaves. Rich in protein, fiber and ash, the succulent mangrove leaves have traditionally been an important source of nutrition for camels and live stock and had been used as fodder for their camels by Bedouins for many generations. As a successful halophyte, that is a plant growing in a high salinity environment, the mangrove has as a result, been the subject of much research by the Egyptian Desert Research Center in Matariya and other research centers which are interested in increasing palatable fodder from the desert as well as those interested in marine agriculture.
But the usefulness of the mangrove does not stop there. In fact man has found many more uses for the wood, roots, leaves, bark, fruit, and seeds of these majestic and mysterious trees. From using the roots and bark as an aphrodisiac to healing snake bites and other skin ailments with its fruits and seeds, man here has also used its wood for firewood and its bark for dyes. It should also be noted that the bark and roots also contain Tannin in considerable amounts, as well as Lapachol, which is an allergic sensitizer.
Finally, the mangrove forest at Ras Mohamed preforms one other very important function and that is forming soil and stabilizing the coastline under the soil surface with its huge mats of submerged thread-like roots.
By Sharm Pro
