Aquatic Ecosystem

Aquatic Ecosystem

Learning Outcomes

At the end of this Lecture, students will
be able to

• Explain Aquatic ecosystem

• Discuss the characteristic features of
Aquatic ecosystem

• Discuss the structure and functional of
the Aquatic ecosystem


• Introduction to Aquatic ecosystem

• Characteristic features of Aquatic

• Structure and functional of the Aquatic


• Aquatic ecosystems constitute the marine
environments of the seas and the fresh water systems in lakes, rivers, ponds
and wetlands

• Provide human beings with a wealth of
natural resources (food such as fish and crustaceans)

• Natural aquatic systems such as rivers
and seas break down chemical and organic wastes created by man

• If aquatic ecosystems are misused or over
utilized, their ability to provide resources suffers in the long term

• Over-fishing leads to a fall in the fish

What is an
aquatic ecosystem?

• In aquatic ecosystems, plants and animals
live in water

• These species are adapted to live in
different types of aquatic habitats

• Aquatic ecosystems may be classified as
being stagnant ecosystems or running water ecosystems

• The mud gravel or rocks that form the bed
of the aquatic ecosystem alter its characteristic and influence its plant and
animal species composition

• The aquatic ecosystems are classified
into freshwater, brackish and marine ecosystems, which are based on the
salinity levels

• The fresh water ecosystems that have
running water are streams and rivers

• Ponds, tanks and lakes are ecosystems
where water does not flow

• Wetlands are special ecosystems in which
the water level fluctuates dramatically in different seasons

• They have expanses of shallow water with
aquatic vegetation, which forms an ideal habitat for fish, crustacea and water

• Marine ecosystems are highly saline,
while brackish areas have less saline water such as in river deltas

• Coral reefs are very rich in species and
are found in only a few shallow tropical seas

• Richest coral reefs in India are around
the Andaman and Nicobar islands and in the Gulf of Kutch

• Brackish water ecosystems in river deltas
are covered by mangrove forests and are among the world’s most productive
ecosystems in terms of biomass production

• The largest mangrove swamps are in the
Sunderbans in the delta of the Ganges