This text for question 1-3
Mangrove Trees
A mangrove is a tropical marine tree or shrub of the genus Rhizhopora. Mangroves have special aerial roots and salt iltering tap roots that enable them to thrive in brackish water (brackish water is salty, but not as salty as sea water). here are several species of mangrove trees found all over the world.
Some prefer more salinity, while others like to be very close to a large fresh water source (such as a river). Some prefer areas that are sheltered from waves. Some species have their roots covered with sea water everyday during high tide. Other species grow on dry land, but are still part of the ecosystem.
Mangroves need to keep their trunk and leaves above the surface of the water. Yet they also need to be irmly attached to the ground so they are not moved by waves. here are three types of mangrove roots that play an important role for it:
(1) . support roots which directly pierce the soil.
(2) . level-growing roots which twist upwards and downwards, eith the upward twists emerging on the water surface.
(3) . level growing roots whose downward twist (sub-roots) appear on the water surface.
Any part of a root that appears above the water lows oxygen to the plant under water surface. As the soil begins to build up, these roots produce additional roots that become embedded in the soil.
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