Question

Based on light penetration, freshwater ecosystem are classified to:

• A. Littoral zone, limnetic zone and profundal zones.
• B. Littoral zone and limnetic zones.
• C. Littoral zone, limnetic zone and bathyal zones.
• D. Euphotic, bathyal and abyssal zones.

Answer 1

The correct option is A Littoral zone, limnetic zone and profundal zones.

The freshwater ecosystem can be classified into littoral zone, limnetic zone, and profundal zones based on the penetration of light.
The shallow zone near the shore, which has an effective light penetration, is called littoral zone. This topmost layer near the water body is the habitat for snails and insects.
The limnetic zone is the open water zone at the top of the water, which receives a good deal of sunlight. Plants like water lily, moses, etc. are found in this region along with different types of algae.
The profundal zone is a deep zone located below the range of effective light penetration. Mostly heterotrophs are found in this region. Animals that live here are predators and scavengers like crabs, snails and turtles.
Based on the light penetration marine ecosystem is classified into euphotic, bathyal, and abyssal zones.