Question

Briefly explain the ecological pyramid which is always upright.

Answer 1

Ecological pyramids are of three general types namely:
(i) Pyramid of numbers, showing the number of individual organisms at each level
(ii) Pyramid of biomass, showing the total dry weight and other suitable measures of the total amount of living matter, and
(iii) Pyramid of energy, showing the rate of energy flow and/or productivity at successive trophic levels. (always upright)

Of the three types of ecological pyramids, the energy pyramids give the best picture of the overall nature of the ecosystem. Here number and weight of organisms at any level depend not on the amount of fixed energy present at any one time in the level just below but rather on the rate at which food is being produced. In contrast with the pyramids of numbers and biomass, which are pictures of the standing situations like organisms present at any moment the pyramid of energy is a picture of the rates of passage of food, mass through the food chain. In shape, it is always upright, as in most of the cases there is always a gradual decrease in the energy content at successive trophic levels from the producers to various consumers.