Ecological Pyramids – Definition, Types, Examples, Significance & Limitations

What are the Ecological Pyramids?

An ecological pyramid is a graphical representation of the relationship between various organisms in a community. Each of the bars that make up the pyramid represents a various trophic level, and their order, which is based upon who eats whom, represents the flow of energy.

Energy moves up the pyramid, beginning with the main producers, or autotrophs, such as plants and algae at the very bottom, followed by the primary consumers, which eat these plants, then secondary consumers, which feed on the primary consumers, and so on. The height of the bars ought to all be the same, but the width of each bar is based upon the quantity of the element being determined.

Kinds of Ecological Pyramids

The eco-friendly pyramids may be of the following three kinds.

1.Pyramid of Number

It illustrates the number of individual organisms at different trophic levels of the food chain. This pyramid was advanced by Charles Elton (1927), who mentioned the great distinction in the number of organisms involved in each step of the food chain. Succeeding links of trophic structure decline rapidly in number till there are very few carnivores at the top.

The pyramid of numbers ignores the biomass of organisms and it likewise does not indicate the energy transferred or using energy by the community involved. The lake community provides a typical example of the pyramid of number.

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2.Pyramid of biomass

This shows the total mass of organisms at each trophic level. Normally, this kind of pyramid is largest at the bottom and gets smaller sized going up, but exceptions do exist. The biomass of one trophic level is computed by increasing the variety of individuals in the trophic level by the typical mass of one individual in a specific area.

This type of ecological pyramid solves some issues of the pyramid of numbers, as it shows a more accurate representation of the amount of energy consisted of in each trophic level, however, it has its own constraints. For instance, the time of year when the data are collected is really important, since various types have different breeding seasons. Also, because it’s normally impossible to measure the mass of every single organism, only a sample is taken, potentially leading to errors. Unit: g m-2 or Kg m-2.


3. Pyramid of Energy

When production is considered in terms of energy, the pyramid shows not only the amount of energy flow at each level, however more crucial, the actual role the numerous organisms play in the transfer of energy. An energy pyramid shows how much energy is needed as it streams up-wards to support the next trophic level.

The pyramid is built according to the rate at which food material (in the form of energy) travels through the food cycle. Some organisms might have small biomass, however, the total energy they take in and hand down may be considerably greater than that of organisms with much larger biomass. Energy pyramids are constantly slopping since less energy is transferred from each level than was paid into it. In cases such as in open water communities, the producers have less bulk than consumers however the energy they keep and pass on should be greater than that of the next level.

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The pyramid of productivity is the most widely utilized kind of ecological pyramid, and, unlike the two other types, can never ever be biggest at the peak and smallest at the bottom. It’s an important type of ecological pyramid since it examines the flow of energy in an environment over time. Units: J m-2 yr-1, where Joule is the unit for energy, which can be interchanged by other units of energy such as Kilojoule, Kilocalorie, and calorie.

Ecological Pyramid Examples

The diagram below is an example of a productivity pyramid, otherwise called an energy pyramid. The sun has actually been included in this diagram, as it’s the primary source of all energy, as well the decomposers, like bacteria and fungi, which can acquire nutrients and energy from all trophic levels by breaking down dead or decaying organisms. The nutrients then go back into the soil and are used up by plants.


The loss of energy to the environments is also shown in this diagram, and the total energy transfer has been computed. We start off with the total quantity of energy that the main producers include, which is indicated by 100%.

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As we go up one level, 90% of that energy is utilized in steps aside from to create flesh. What the primary consumers end up with is simply 10% of the beginning energy, and, 10% of that 10% is lost in the transfer to the next level. That’s 1%, and so on. The predators at the apex, then, will just get 0.01% of the beginning energy! This inefficiency in the system is the reason that energy pyramids are always upright.

Significance of Ecological Pyramid

The significance of an eco-friendly pyramid can be discussed in the following points:

  • They reveal the feeding of different organisms in various environments.
  • It reveals the effectiveness of energy transfer.
  • The condition of the ecosystem can be kept track of, and any further damage can be prevented.
Limitations of the Ecological Pyramid

More than one type might inhabit several trophic levels as in the case of the food web. Therefore, this system does not take into account food webs.

  • The saprophytes are not considered in any of the pyramids although they form a fundamental part of the various community.
  • These pyramids are applicable just to basic food chains, which usually do not occur naturally.
  • These pyramids do not provide any principle in relation to variations in season and environment.
  • They do not consider the possibility of the presence of the same species at different levels.