Draw a lake showing different zones. Why are they called so?
Zones of Lake :
1) Littoral zone :
The zone close to shore. They reaches all the way. Plants living in this zone perform photosynthesis.
2) Limnetic zone :
Sunlit part of the lake surrounded by the littoral zone. This zone extends at a depth where sunlight penetrates.
3) Profundal zone :
It is much colder and denser than previous zones.
Question 9.
Collect information of one lake from internet and prepare a table of organisms adapted at different zones.
Answer:
Different zones in lakes and types of organisms present:
1) The littoral zone :
a) The topmost and warmest zone at the edge of a water body is home to snails, clams, insects, several crustaceans, fishes and amphibians and eggs and larvae of dragonflies.
b) Plants like mosses, water lily, vallisneria, hydrilla etc. are found along with several types of algae.
c) Predators of this zone are tortoise, snakes and ducks.
2) The limnetic zone :
a) This zone contains variety of fresh water fish with bright shiny scales.
b) Transparent or whitish bodied crustaceans like daphnia, cyclops, small shrimps are also found in this zone.
c) There are different types of floating plants like water hyacinth wolfia, pistia along with a variety of algae.
3) The profundal zone :
a) Mostly heterotrophs are present.
b) Scavengers and predators like crustaceans, crabs, fishes like eels and glossogobius (isika dondu), snails, turtles etc are present.
c) Many kinds of bacteria are also present in this zone that help in decomposition.
1) Littoral zone :
The zone close to shore. They reaches all the way. Plants living in this zone perform photosynthesis.
2) Limnetic zone :
Sunlit part of the lake surrounded by the littoral zone. This zone extends at a depth where sunlight penetrates.
3) Profundal zone :
It is much colder and denser than previous zones.
Question 9.
Collect information of one lake from internet and prepare a table of organisms adapted at different zones.
Answer:
Different zones in lakes and types of organisms present:
1) The littoral zone :
a) The topmost and warmest zone at the edge of a water body is home to snails, clams, insects, several crustaceans, fishes and amphibians and eggs and larvae of dragonflies.
b) Plants like mosses, water lily, vallisneria, hydrilla etc. are found along with several types of algae.
c) Predators of this zone are tortoise, snakes and ducks.
2) The limnetic zone :
a) This zone contains variety of fresh water fish with bright shiny scales.
b) Transparent or whitish bodied crustaceans like daphnia, cyclops, small shrimps are also found in this zone.
c) There are different types of floating plants like water hyacinth wolfia, pistia along with a variety of algae.
3) The profundal zone :
a) Mostly heterotrophs are present.
b) Scavengers and predators like crustaceans, crabs, fishes like eels and glossogobius (isika dondu), snails, turtles etc are present.
c) Many kinds of bacteria are also present in this zone that help in decomposition.
