What are the adaptive features of mangrove plants?

Answer 1

Mangroves have physically adapted their leaves, roots and reproductive methods in order to survive in a harsh environment of soft, low oxygen soils and varying salinity. Their leaves excrete salt, hey have far reaching, exposed roots, and the have evolved to produce leaves that float.
Mangroves have stilt-like roots and stems to help adjust to the water level. Because of this, they are able to thrive near the tidal shores.

Answer 2

Mangroves have physically adapted their leaves, roots and reproductive methods in order to survive in a harsh environment of soft, low oxygen soils and varying salinity. Their leaves excrete salt, hey have far reaching, exposed roots, and the have evolved to produce leaves that float.
Mangroves have stilt-like roots and stems to help adjust to the water level. Because of this, they are able to thrive near the tidal shores.

Answer 3

Mangrove trees have adapted to living in waterlogged swamps by developing a root system that supports it in soggy ground. The also have an adaptation that allows it to take in more carbon dioxide through the branches.

Answer 4

Mangrove adaptations to their environmentMangroves have had to physically adapt their leaves, their roots and their reproductive methods in order to survive in a harsh, dynamic environment of soft, low oxygen soils and varying salinity.

Leaf adaptations to saline conditions

• Many mangrove species, such as the Grey Mangrove and the River Mangrove (common species along the Redlands coast), have leaves with glands that excrete salt.
• Some species such as the Grey Mangrove can also tolerate the storage of large amounts of salt in their leaves - which are discarded when the salt load is too high.
• Mangroves can also restrict the opening of their stomata (these are small pores through which carbon dioxide and water vapour are exchanged during photosynthesis). This allows the mangrove to conserve its fresh water, an ability vital to its survival in a saline environment.
• Mangroves are able to turn their leaves to reduce the surface area of the leaf exposed to the hot sun. This enables them to reduce water loss through evaporation.

Root adaptations to soft, saline, low oxygen soils

• A distinctive feature of mangroves is their far-reaching, exposed roots. While these roots come in many different shapes and sizes, they all perform an important function - structural support in the soft soils.
• Some species of mangroves have pneumataphores, which are above-ground roots. These are filled with spongy tissue and peppered with small holes that offer structural support and allow oxygen to be transferred to the roots trapped below ground in the anaerobic (low oxygen) soils.
• The roots of many mangrove species are also adapted to stop the intake of a lot of the salt from the water before it reaches the plant.

Reproductive adaptations to tidal environment

• Some mangrove species have evolved to produce seeds that float. The tide acts as the method of dispersal to avoid crowding of young plants.
• Other mangrove species are viviparous. They retain their seeds until after it has germinated and a long, cylindrical propagule has formed. When it has matured to this stage, the parent tree drops it into the water, where it remains dormant until it finds the soil and is able to put out roots.

Answer 5

The mangrove trees physically adapt their leaves and roots to the environment's low oxygen soils. It also adapts its reproductive methods in order to survive in the varying salinity of the mangrove.

Answer 6

MANGROVE ADAPTATIONS

In general, mangrove species share 4 important traits that allow them to live successfully under environmental conditions that often exclude other species. Some of these adaptations include: morphological specialization, i.e., aerial prop roots, cable roots, vivipary, and other features that enable mangroves to adapt and thrive in their environments; the ability to excrete or exclude salts; habitat specificity within estuaries, with no extension into upland terrestrial communities; and taxonomic isolation from other genetically related species inhabiting upland communities (Tomlinson 1986).

Root Aeration

Another adaptation exhibited by mangroves is observed in root aeration. Soils in mangrove areas tend to be fairly exotic, preventing many types of plants from taking root. Mangroves have adapted to this condition by evolving shallow root systems rather than deep taproots. Red mangroves aerate their roots by way of drop roots and prop roots which develop from lower stems and branches, and penetrate the soil only a few centimeters. Prop roots act to both stabilize the tree and provide critical aeration to the roots. The above-ground areas of these roots are perforated by many small pores called lenticels that allow oxygen to diffuse first into cortical air spaces called aerenchyma, and then into underground roots (Scholander et al 1955, Odum and McIvor 1990). Water is prevented from entering the tree via lenticels due to their highly hydrophobic nature which allows the red mangrove to exclude water from prop roots and drop roots even during high tides (Waisel 1972).

Black mangroves utilize a different strategy for aeration of root tissues. Black mangroves have cable roots which lie only a few centimeters below the soil surface, and radiate outward from the stem of the tree (Odum and McIvor 1990). A network of erect aerial roots extends upward from the cable roots to penetrate the soil surface. These erect roots, called pneumatophores, contain lenticels and aerenchyma for gas exchange, and may form dense mats around the base of black mangrove trees, with pneumatophores attaining as much as 20 cm or more in height depending on the depth of flood tides (Odum and McIvor 1990).

Salt Balance

Mangroves are facultative halophytes, meaning they have the ability to grow in either fresh or salt water depending on which is available. However, despite the fact that mangroves are able to grow in fresh water, they are largely confined to estuaries and upland fringe areas that are at least periodically flooded by brackish or salt water (Gilmore and Snedaker 1993). Mangroves are rarely found growing in upland communities. Simberloff (1983) and Tomlinsion (1986) suggested that one reason mangroves do not develop in strictly freshwater communities is due to space competition from freshwater vascular plants. By growing in saline water, mangroves reduce competitive threat, and thus are able to dominate the areas they grow in.

As facultative halophytes, mangroves not only tolerate, but thrive under saline conditions. They accomplish this either by preventing salts from entering their tissues or by being able to excrete excess salts that are taken in. Red mangroves (Rhizophora mangle), for example, exclude salts at their root surfaces. This is accomplished non-metabolically via a reverse osmosis process driven by transpiration at leaf surfaces in which water loss from leaves produces high negative pressure in xylem tissue. This, in turn, allows water to freely diffuse into plant tissues. In addition to excluding salts, red mangroves also have the ability to exclude sulfides from their tissues. This sometimes results in elevated pore water concentrations of sulfides in localities where poor flushing of the mangrove area is common (Carlson and Yarbro 1987).

In contrast to salt exclusion observed in red mangroves, other species such as black mangroves, white mangroves and buttonwoods each utilize salt excretion as a salt-balancing mechanism. Salt concentrations in the sap of these species may be up to ten times higher than in species that exclude salts (Odum and McIvor 1990). Salt-excreting species are able to take in high salinity pore water, and then excrete excess salts using specialized salt glands located in the leaves. Atkinson et al. (1967) suggested this process involved active transport, and thus required energy input from mangroves to drive the process.

Answer 7

Mangroves have had to physically adjust their reproductive methods, their leaves, and their roots in order to withstand the varying salinity and low oxygen soils. Some mangroves have developed seeds that float as the tide aides in dispersing the seeds in order to prevent crowding of tiny young plants.

Answer 8

· Grow in salt water regions .

· The biggest problem mangroves face is nutrient uptake.

· They limit the amount of water they lose through their leaves

· coastal habitats and oxygen-deficient plants

Answer 9

Mangrove trees get more oxygen by taking in air through pores in its bark.