2. DEFINITION
An aquatic ecosystem includes a group of interacting organisms which are
dependent on one another and their water environment for nutrients and
shelter. Examples of aquatic ecosystem include oceans, lakes and rivers.
The word 'aquatic' is derived from the Latin word 'aqua', which means
water.
So, in a water-based setting, an aquatic ecosystem is a community of
species that live together, interact, and to some extent rely on one another.
Habitat is a part of an ecosystem.
The climate, plants, and animals are the identities of a habitat
3. TYPES
AQUATIC OR WATER ECOSYSTEM.
FRESH WATER ECOSYSTEM
LENTIC
POND
LAKE
LOTIC
STREAM
RIVER
WETLANDS
MARINE ECOSYSTEM
OCEAN
COASTAL
4. FRESH WATER
ECOSYSTEM
Covers nearly 0.8 per
cent.
LENTIC ECOSYSTEM
Include all ecosystems with static or
still water
Lakes and ponds are examples.
Algae, crabs, shrimp & amphibians
live in these habitat
Also called lacustrine ecosystem or
stil water ecosystem
LOTIC ECOSYSTEM
Rapidly flowing waters that move in
a unidirectional way
Includes river and streams
Harbors insects such as beetles,
mayflies,
also called riverine ecosystem
5. POND AND LAKE ECOSYSTEM
On the basis of water depth and types of vegetation and animals
there may be three zones in a lake or pond littoral, limnetic and
pro-fundal.
The
Littoral
Zone is the shallow
Water region which is
Usually occupied by rooted plants.
The limnetic-zone ranges from the shallow to the depth of
effective light penetration and associated organisms are
small crustaceans, rotifers, insects, and their larvae and
algae.
The pro-fundal zone is the deep water parts where there is no
effective light penetration. The associated organisms are snails,
mussels, crabs and worms
7. BIOTIC COMPONENTS
PRODUCERS
Main producers are algae and other
aquatic plants, such as azolla,
hydrilla, pistia, wolffia.
Are either floating or suspended or
rooted at the bottom.
The green plants convert the radiant
energy into chemical energy through
photosynthesis.
The chemical energy stored in the
form of food is utilized by all the
organisms.
Oxygen evolved by producers in
photosynthesis is utilized by all the
living organisms in respiration.
CONSUMERS
the primary consumers are tadpole
larvae of frogs, fishes and other
aquatic animals which consume
green plants and algae as their food.
These herbivorous aquatic animals
are the food of secondary
consumers.
Frogs, big fishes, water snakes, crabs
are secondary consumers.
In the pond, besides the secondary
consumers, there are consumers of
highest order, such as water-birds,
turtles
DECOMPOSERS AND
TRANSFORMERS
When aquatic plants and animals
die, a large number of bacteria
and fungi attack their dead
bodies and convert the complex
organic substances into simpler
inorganic compounds and
elements. These micro-organisms
are called decomposers
chemical elements liberated by
decomposers are again utilized
by green plants in their nutrition
8.
9. TERTIARY
CONSUMER
10 kcal
SECONDARY CONSUMER
100 Kcal
PRIMARY CONSUMERS
1000 Kcal
PRODUCERS
10,000 kcal
Decr
ea
sing
rate
of
energy
flow
PYRAMID OF ENERGY
Out of the total energy available at a particular trophic level, only 10% is passed
on to the next trophic level. making it impossible for energy to flow in reverse
direction
10. • EPILIMNION - The uppermost and warmest layer (also called the
mixed layer) of a lake that experiences density stratification
induced by seasonal warming at the lake surface.
• METALIMNION - A layer of transitional density and
temperature that connects the epilimnion to the hypolimnion.
• HYPOLIMNION - The most dense, deepest, and coolest layer of a
thermally stratified lake.
does not support photosynthesis, because it lacks solar irradiance,
and in many cases shows partial or complete depletion of
dissolved oxygen.
STRATIFICATION OF LAKE AND POND ECOSYSTEM
11.
12. STRATIFICATION OF LAKE AND POND ECOSYSTEM
• APHOTIC - Without light, generally interpreted limno-logically as
receiving less than 1% of solar irradiance reaching a lake surface.
• EUPHOTIC - That portion of a lake receiving sufficient solar irradiance
to support photosynthesis (typically more than 1% of full solar
irradiance).
• LITTORAL - Near the shore of a waterbody, where irra-diance reaching
the bottom is above 1% of solar irradiance at the water surface.
• PELAGIC - Beyond the littoral zone of a lake.
• BENTHIC - The zone of a lake extending a few centimeters above and
below the bottom of the lake.
13. THREATS TO ECOSYSTEM
Stress on an aquatic ecosystem can be a result of physical, chemical or
biological alterations to the environment.
THREATS TO ECOSYSTEM
PHYSICAL ALTERATIONS
include changes in water
temperature, water flow
and light availability.
CHEMICAL ALTERATIONS
include changes in the
loading rates of
biostimulatory nutrients,
oxygen-consuming
materials, and toxins.
BIOLOGICAL
ALTERATIONS
include over-harvesting
of commercial species
and the introduction of
exotic species
14. • Educating about water-related issues
• Environmental education centres located adjacent to wetlands, rivers & other
natural features enhance public awareness of the feature.
• Development of recreational zones by developing gardens, parks and
introduction of water sports.
• Construction of a boundary wall after proper survey to prevent encroachment.
• Reducing the pollution of the lake and improving the water quality by
disiltation, Bio-Remediation, and through various measures such as flap gates,
construction of dhobi ghats and toilets, watershed management techniques,
etc.
• Building embankments, walkways and pathways to the water bodies Planting
trees, and creating gardens.
• Installing docks, deploying boats and canoes.
• Allocating funds for annual maintenance.
SOLUTIONS