Page 45 - Photosynthesis: The Green Miracle

Harun Yahya

The Fascinating Leaves of Plants in
Watery Habitats

Plants that live in lakes, by the sea, in salt water and marshes with
high salt levels encounter similar difficulties to those in deserts. But as is
the case with all living things, plants living in such regions have been cre-
ated with characteristics totally suited to their habitats. These plants’
leaves and stem structures, the greater part of which lies under water, have
been specially designed to permit them to survive under such conditions.
For example, plants that live in salt water have thick, leathery leaves much

like desert-dwelling plants. This gives them the ability to store high levels
of fresh water in their tissues without being damaged by excessive salt.
In the brackish regions where plants such as samphire, and seablite
live, they are frequently exposed to flooding, which causes a large quan-
tity of salt to enter the roots of the plant, which will ordinarily be harm-
ful. Yet these plants are not harmed by excessive salt because they have
special glands that remove the excess salt from their tissues. Plants that

live under such conditions are known as halophytes. 16
Salt marsh plants such as the glasswort are regularly surrounded by
sea water. Plants of this kind survive thanks to letting their leaves remain
on the water’s surface, buoyed by the presence of special air-filled struc-
tures underneath. Giant Amazonian lilies are one of the species that pos-
sess such leaves.
The roots of plants that live in water or in water-logged soil are com-
pletely saturated, which raises the question of how such plants can obtain
air. Like the other plants we’ve discussed, species that live with their roots

in water possess the ideal characteristics for their environment. For exam-
ple, a tissue known as aerenchyma permits those parts of marsh plants that
remain under water to obtain oxygen. Air pockets in these tissues has the
ability to expand. In plants such as the water lily and Elodea, oxygen is
transmitted from the trunk and leaves, those parts of the plant that lie out-
side the water, to the lower regions under water. 17

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