What are the three types of ecological pyramids. What information is conveyed by each pyramid with regard to structure, function and energy in the ecosystem.

Ecological Pyramids: An ecological pyramid is a graphical representation of an ecological parameter as number of individual present in various trophic level of food chain.
Properties of ecological pyramid-
(i)  The trophic structure of an ecosystem is represented in the form of ecological pyramids.
(ii)  The base of each pyramid represents the producers or the first trophic level, while the apex represents tertiary or top level consumer.
The three types of ecological pyramids are-
(a)  Pyramid of number- shows relationship between producers and consumers in an ecosystem in terms of numbers. It may be inverted or upright pyramid.

(b)   Pyramid of biomass- shows relationship between producers and consumers in an ecosystem terms of biomass. It can be
1. Upright, e.g., in case of grass land ecosystem.

2. Inverted, e.g., in case of pond ecosystem- Small standing crop of phytoplankton supports large standing crop of zooplankton.
(c)  Pyramid of energy- is the relationship between producers and consumers in an ecosystem in terms of flow of energy. It is always upright because energy is always lost as heat at each step.

An ideal pyramid of energy. Observe that primary producers convert only 1% of the energy of the sunlight available to them into Net Primary Productivity.