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2 Overview of the Aquatic Ecosystem
Sea bottom
Sea bottom
Sea bottom
Algae
Algae
Algae
Hanging pole
String
String
Hanging pole
Water Surface
Water Surface
Water Surface
(a)
(b)
(c)
Fig. 2.6 An illustration of the three methods of cultivation of red algae. a Broadcast, b off-bottom
and c longline methods
In the broadcast method, algae seedlings are cultivated close to the bottom of the
water. This is usually in slow-moving shallow waters in ponds or lakes or artificial
water systems. In the off-bottom method, the algae seedlings grow on lines tied to
poles such that the algae extend about 20 cm from the bottom of the water, midway
in the shallow water depth. In the longline method, the algae seedlings grow closer
to the surface hanging from ropes attached to poles. Different algae species have
preferences for particular growth method.
2.3.3 Aquatic Animals
These include the vertebrates: amphibians, mammals, birds, fish and reptiles as
well as invertebrates such as crustaceans, mollusks, insects, squids, echinoderms.
Although some mammals, amphibians and birds spend some, most or all of their
time outside of water, they are classified as aquatic if they mostly depend on water
for their survival and feeding. Examples are polar bears who mainly feed on seals
and the kingfisher birds that feed on small fish from rivers. Some of the animals of
2 Overview of the Aquatic Ecosystem
Sea bottom
Sea bottom
Sea bottom
Algae
Algae
Algae
Hanging pole
String
String
Hanging pole
Water Surface
Water Surface
Water Surface
(a)
(b)
(c)
Fig. 2.6 An illustration of the three methods of cultivation of red algae. a Broadcast, b off-bottom
and c longline methods
In the broadcast method, algae seedlings are cultivated close to the bottom of the
water. This is usually in slow-moving shallow waters in ponds or lakes or artificial
water systems. In the off-bottom method, the algae seedlings grow on lines tied to
poles such that the algae extend about 20 cm from the bottom of the water, midway
in the shallow water depth. In the longline method, the algae seedlings grow closer
to the surface hanging from ropes attached to poles. Different algae species have
preferences for particular growth method.
2.3.3 Aquatic Animals
These include the vertebrates: amphibians, mammals, birds, fish and reptiles as
well as invertebrates such as crustaceans, mollusks, insects, squids, echinoderms.
Although some mammals, amphibians and birds spend some, most or all of their
time outside of water, they are classified as aquatic if they mostly depend on water
for their survival and feeding. Examples are polar bears who mainly feed on seals
and the kingfisher birds that feed on small fish from rivers. Some of the animals of