Let us see, how we can represent the quantity of the loss of matter in the different trophic levels in the form of a pyramid. Suppose the herbivores in a food chain feeds on 100 kg of plant tissues. Is there an increase of 100 kg in their body mass? It is sure that the answer is 'No'. If we consider that the increase is only 10 kg, it is clear that the body mass of the carnivores that feed on them does not show any proportional increase. At the upper trophic levels there is only a nominal increase in their body mass.
If the different living beings at different trophic levels are arranged one above the other on the basis of their biomass will it form a pyramid? Such a representation is called the pyramid of biomass. Demonstrate a biomass pyramid by considering a food chain.