Question

A habitat not suitable for primary productivity is
A) Cave
B) Pond
C) Meadow
D) Forested river bank

Answer 1

Let us first understand what is meant by habitat and primary productivity. Habitat is a natural environment where plants, animals and other organisms coexist. Primary productivity is the rate of conversion of energy to organic compounds by photosynthetic organisms. They obtain nutrients and energy by harnessing sunlight.

Complete answer:
A) Cave: It is a natural void in the ground formed by the weathering of rocks. The photosynthetic producers are rarely found inside the cave as there is no availability of sunlight. Hence it is not suitable for primary productivity.
B) Pond: It is a freshwater habitat that is filled with water, plants and other aquatic animals. It has photosynthetic producers as well as adequate sunlight for primary productivity.
C) Meadow: it is a field or open habitat usually looked after by humans for the production of fodder or livestock. They are covered with shrubs, herbs and other non woody plants. They are ecologically important as they attract multiple wildlife.
D) Forested river bank: It is also called a riparian forest habitat where 'ripa' is a Latin which means river bank. This is a habit where aquatic life and the terrestrial life coexist. It is the best suited habitat for primary productivity.

Therefore the correct answer is (A) Caves.

Note: Though cave is not suitable for primary productivity, cave habitat has 3 zones

Twilight zone: the area from entrance to the distance as far as human vision possible. There is some light and diversity of life can be found.
Middle zone: the region just beyond the twilight zone where there is total darkness and humidity and temperature varies daily.
Zone of total darkness: it is the region of complete darkness and temperature falls below 0 degrees.