Mangrove Forests
Mangroves are woody, specialized types of trees of the tropics that can live on the edge, where rainforests meet oceans. Found on sheltered coastlines and river deltas, the y grow in brackish wetlands between land and sea where other plants can't grow. They protect the coastline and prevent e rosion by collecting sediment from the rivers and streams and slowing down the flow of water. There are about 39.3 million acres of mangrove forests in the warm coastlines of tropical oceans all over the world. More than 10.5 million acres, or 27% of mangrove forests are found in Southeast Asia. Mangrove trees look as if they grow on stilts. The stilts are their specialized aerial roots which hold the trunk and leaves above the water line. Mangrove forests are affected by the rising and falling of the ocean's tides. The aerial roots and tap roots can filter out the salt in the brackish water they grow in. Support roots grow directly into the mud to anchor the tree. Other roots snake up and down with the upward loops rising above the salt water level. Salt crystals taken up by the roots are stored in the leaves. The mangrove rids itself of the salt by shedding its leaves after a while. It is believed that the earliest ear liest species of mangroves came from the Southeast Asian region. There are more mangrove species in this region than anywhere else in the world. It is thought that seeds of the mangrove moved westward to India, East Africa and finally to Central and South America on ocean currents 23 to 66 million years ago. Mangroves of the Americas have similar but fewer species than those in Africa and far less than Southeast Asia. The specialized seeds of the mangroves are tough and float, and can travel great distances in salt wate r and take root far from its parent tree. The seeds see ds germinate and grow into seedlings right on the parent tree. During this time t hey acquire the carbohydrates they need later to g row on their own. The tree eventually drops its seedlings, where they may take root in the mud below, or are swept out by the tide. One of the most biologically diverse forests, mangrove forests are known as the "rainforests by the sea". The forests are the breeding grounds for fish, shrimp, prawns, crabs, shellfish and snails. Mud skippers are found in mangrove forests. The mudskipper has made adaptations so it can skim across the mud during low tide when the ground is uncovered in many places, traveling from puddle to puddle. Mangrove forests are also nesting sites for m any shore birds and home to crab eating monkeys and proboscis monkeys, fishing cats, lizards, sea turtles, and many more animals. For many species of fruit bats, like the dawn bat, mangrove blossoms and fruit make up a large part of their diet.
Dipterocarp forests
Deciduous dipterocarp forests The Dipterocarpaceae are a large family of tr opical hardwood trees that are long-lived and can grow to exceptional sizes.
Most are evergreen and occur in wet rainforests. Many of these wet forest trees are prized for their timber. The fruits of dipterocarp trees have conspicuous, long wings (sepals) to aid in dispersal by wind. However, of the estimated 680 species, only 6 are deciduous - and all 6 of these are found in the Dry Forests.
This deciduous habit is not, as usual, a response to cold, but r ather to a lack of water. In the dry season, these trees lose their leaves as an adaptation to prevent a major source of wat er loss. Only in small, wetter patches in the Dry Forests with better soils, are evergreen tree species able to survive.
Dipterocarps in the Dry Forests are found in the more arid areas, on poorer soils. They often form open canopy woodlands with a grassy understorey, but sometimes occur in a savanna type formation over large grasslands.
Molave Forest/ Dry Forest
Tropical Dry Forest This forest type typically experiences an annual hard dry season. The average rainfall is sufficient enough to promote growth of trees, but these tree and plant species must be able to withstand periods of low precipitation and moisture. Many of the tree species in dry forest are also deciduous. During the driest months these species will drop their leaves much in the same manner that northern deciduous forest species loose their leaves in the fall and winter. This dry season leaf-drop reduces the water needs of the plant, as there is no evapotranspiration through the leaves. Much of the dry forests of Mexico and Central America have be en converted into cattle ranches and planted in exotic grasses. These introduced plant species provide forage for livestock, but in t urn, change the habitat, and displace native forest species. These native plant species are what comprise the forest habitat needed for both the plants and animals that form the dry forest ecosystem.
Coastal Forest
Climate: Coastal Forest develops where rainfall is usually greater t han 700 mm per year, and is more prevalent in summerrainfall regions. Temperatures are never extreme due to the moderating maritime influence and species distributions may be limited in the south by the colder climates. For example, Natal Wild Banana Strelitzia nicolai is a common tree in the forest as far south as East London. Apart from rainfall and temperature, important environmental parameters are wind and salt spray. The tall trees may be severely "pruned" by high winds and salt damage and this restricts the distribution of forest on exposed dunes, especially along the Eastern Cape coast. Geology & Soil: The vegetation develops on deep consolidated calcareous sands and there is generally little soil development. An orthic A horizon generally overlies regic sand giving a F ernwood soil form. Soils are generally alkaline and mediumto coarse-grained. Economic Uses: Trees are utilized mainly for firewood and structural timber. Many species are used for muti. Conservation Status: Coastal Forest is well-conserved in some reserves in KwaZuiu-Natal and Eastern Cape. The main threat is due to holiday resort expansion along parts of the coastline, dune mining in some limited localities, and the use of firewood, building materials and muti plants in rural regions.
Bamboo Forests
Bamboo forests can be found most numerously in China, Japan and the East and Southeast Asian regions of the world. But they can also be found in Northern Australia, India, sub-Saharan Africa and the tropical regions of the Americas. Bamboo forests differ greatly from hardwood forests, especially in terms of the growth cycle of the bamboo plants themselves. Bamboo forests have been used by humans as a source for food and building materials for many centuries, and they are still used, e specially in Asia, for those same purposes today. In addition to their material importance, bamboo forests are culturally symbolic in countries like China and Japan. In China, bamboo is a symbol of longevity, and bamboo groves are a common sight in Buddhist temples. In Japan’s Shinto religion, bamboo forests are often the site of shrines and altars, as bamboo forests are believed to ward off evil spirits. The Growth Cycle of Bamboo Forests While hardwood forests can take hundreds of years to form, bamboo forests grow very rapidly and can produce fully mature bamboo plants, the stalks of which can reach up to 20 to 30 feet in height or more, within 3 to 7 years. This is because bamboo is not a wood tree at all, but a type of giant grass, and as such bamboo plants grow to their full height and g irth within a single growing season that lasts 3 to 4 months. After the bamboo plant’s shoots die, they fall and are replaced by new ones. Each consecutive shoot that sprouts from the main plant root system is thicker and taller than the one before, and like the one before it, it will achieve its full growth potential during a single growth season
