Question

Which ecological pyramid can never be inverted?

Answer 1

Hint: Ecological Pyramids are graphic representations of various ecological parameters at the successive trophic levels of food chains with producers at the base, top carnivores at the apex and intermediate levels in between. Quantity of each level is indicated by the length of the bar in the graph. Common parameters used in preparing ecological pyramids are numbers of individuals, biomass, and energy at different trophic levels.

Complete answer:
Types of ecological pyramids:-
Pyramid of Numbers: It is a graphical representation of numerical strength of various populations in different trophic levels per unit area of an ecosystem with producers forming base, intermediate levels forming intermediate tiers, and apex formed by top carnivores. Length of each trophic level is proportional to the number of individuals at that level.
Pyramid of Biomass: Biomass is the amount of living matter measured in terms of fresh or dry weight . Pyramid of biomass is a graphical representation of the amount of biomass per unit area sequence wise in rising trophic levels with producers at the base and top carnivores at the apex. Biomass is maximum in producers.
Pyramid of Energy: It is a graphic representation of energy per unit area sequence wise in various rising trophic levels with producers at the base and top carnivores at the apex. Length of bar at each level is proportional to the amount of energy present at that level. Maximum energy is found at producer level. The $10\%$ Energy Transfer Law was put forth by Lindemann. According to this law , $90\%$ of the energy captured from the previous trophic level is lost as heat to the environment and only $10\%$ is available to the next trophic level.

The Pyramid of Energy is upright in all cases. It can never be inverted.

Note:
Ecological Pyramids were first prepared by Elton. Hence they are also called Eltonian Pyramids. Pyramid of Energy is highly informative as it gives precise data regarding the amount of energy required to support a trophic level in the ecosystem. It is based upon productivity instead of standing crops.