Why are oceans least productive ?
Sea/ocean is less producer because $(i)$ It receives solar radiation in insufficient amount because sunlight decreases as the depth of sea increases.
$(ii)$ Sea water lacks Nitrogen, Which is an important nutrient substance for plants.
$(iii)$ Excessive amount of salts is not favourable for all plants.
$(iv)$There is no base to support plants
Which one of the following system constitutes the primary producers
Fill in the trophic levels $(1, 2, 3$ and $4)$ in the boxes provided in the figure.
Assertion : A network of food chains existing together in an ecosystem is known as food web.
Reason : An animal like kite cannot be a part of a food web.
Which of the following are consumers of second order
The correct path of energy flow in an ecosystem is