Ecological pyramids

Ecological pyramids are a graphical representation or pyramid shaped diagram which depicts the number of organisms, biomass and productivity at each trophic level of the ecosystem. The bottom of the ecological pyramid consists of the producers and progresses gradually from primary consumers to secondary consumers and finally the tertiary consumers.

The concept of ecological pyramid was developed by Charles Elton and hence ecological pyramids are also called “Eltonian pyramids.”

There are 3 types of ecological pyramids, namely: 

• Pyramid of energy

The pyramid of Energy depicts an upward decrease in energy flow through the trophic levels. This loss in energy is in the form of heat, respiration etc.

• Pyramid of numbers and

The pyramid of energy shows the quantitative relationship between the different trophic levels in terms of number of organisms present per trophic level. The number of organisms progresses in an upward decrease.

• Pyramid of biomass.

The pyramid of Biomass represents the amount of energy in terms of organic matter of organisms available at each trophic level. The producers have a higher biomass and it decreases upwards.

Example: A producer in the lowest trophic level can be assumed to be the plants. These plants are consumed by the primary consumers like deer’s and rabbits. A snake feeds on the rabbit or deer and becomes the Secondary consumer. A lion at the top of the pyramid is the tertiary consumer which consumes the secondary consumer.