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“salt excluder”, and Aegiceras has salt glands and is a “salt excluder”).
Mangroves also show morphological characteristics related to their "physiologically xerophytic" habitat (where water must be conserved to reduce the intake of high salinity water). Thus, many have water storage tissues in their leaves (Avicennia, Aegiceras, Lumnitzera (Fig 6), Kandelia). Many have a waxy thick cuticle and epidermis, and have stomata restricted to the lower leaf surface (Avicennia, Aegiceras, Kandelia, Excoecaria). In Avicennia the stomata are sunken and this species also has the undersurface of its leaves covered by blunt hairs (trichomes) to prevent water loss (Fig 7). Heritiera has its lower leaf surfaces covered with scales for the same purpose.
In summary, this plant community is one of the most remarkable aggregations of unrelated families of plants in the world, which have developed in common a number of special characteristics such as modified roots for support and gaseous exchange, water conservation mechanisms, 'salt balance' mechanisms and a viviparous seedling habit.
Why are mangrove plants important?
Because of their relatively high natural productivity which may be more than twenty times that of the plankton of open ocean waters and five times that of the plankton of rich coastal waters, mangrove plants are able to support a large number and a wide variety of consumer animals. The falling leaves and other plant debris from the mangroves may either be eaten directly or (and this refers to the greater part) it is colonized by bacteria and fungi and partially decomposed before it becomes available to most marine animals. The leaf particles with their associated rich colonies of microorganisms are then eaten by small fish. Much of the leaf material itself is not digested but is passed back into the water where recolonization by microorganisms begins the cycle again. Eventually the very smallest particles (detritus) will be consumed by detritus feeding animals such as molluscs and crustaceans. At the same time algae will be feeding on the dissolved nutrients released, and they in turn form the diet for more consumers.
Thus, fish, shrimps and oysters all depend on the mangroves for their basic food supply. Man has learned to exploit this fact and the commercial rearing of all three groups of animals is common in
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"salt excluder”, and Aegiceras has salt glands and is a “salt excluder”).
Mangroves also show morphological characteristics related to their "physiologically xerophytic" habitat (where water must be conserved to reduce the intake of high salinity water). Thus, many have water storage tissues in their leaves (Avicennia, Aegiceras, Lumnitzera (Fig 6), Kandelia). Many have a waxy thick cuticle and epidermis, and have stomata restricted to the lower leaf surface (Avicennia, Aegiceras, Kandelia, Excoecaria). In Avicennia the stomata are sunken and this species also has the undersurface of its leaves covered by blunt hairs (trichomes) to prevent water loss (Fig 7). Heritiera has its lower leaf surfaces covered with scales for the same purpose.
In summary, this plant community is one of the most remarkable aggregations of unrelated families of plants in the world, which have developed in common a number of special characteristics such as modified roots for support and gaseous exchange, water conservation mechanisms, 'salt balance' mechanisms and a viviparous seedling habit.
Why are mangrove plants important?
Because of their relatively high natural productivity which may be more than twenty times that of the plankton of open ocean waters and five times that of the plankton of rich coastal waters, mangrove plants are able to support a large number and a wide variety of consumer animals. The falling leaves and other plant debris from the mangroves may either be eaten directly or (and this refers to the greater part) it is colonized by bacteria and fungi and partially decomposed before it becomes available to most marine animals. The leaf particles with their associated rich colonies of microorganisms are then eaten by small fish. Much of the leaf material itself is not digested but is passed back into the water where recolonization by microorganisms begins the cycle again. Eventually the very smallest particles (detritus) will be consumed by detritus feeding animals such as molluscs and crustaceans. At the same time algae will be feeding on the dissolved nutrients released, and they in turn form the diet for more consumers.
Thus, fish, shrimps and oysters all depend on the mangroves for their basic food supply. Man has learned to exploit this fact and the commercial rearing of all three groups of animals is common in
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