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A mangrove is a tropical marine tree or shrub of genus Rhizhopora. Mangroves have special aerial roots and salt-filtering tap roots that enable them to thrive in brackish water (brackish water is salty, but not as salty as sea water).
There 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 river). Some prefer areas that are sheltered from waves. Some species have their roots covered with sea water every day during high tide. Other species grow on dry land, but are still part of the ecosystem.
1. Support roots which directly pierce the soil.
2. Level – growing roots which twist upwards and downwards, with the upward twist 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 flows 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.
“... that enable them to thrive in brackish water.” (paragraph 1)
The underlined word has the same meaning as .....