Types of Ecological Pyramids

An ecological pyramid (also known as a trophic pyramid, Estonian pyramid, energy pyramid, or food pyramid) is a graphical representation of the biomass or bio productivity at each trophic level in a given ecosystem.

A biomass pyramid shows how much biomass (the amount of living or organic matter present in an organism) is present in the organisms, whereas an energy pyramid shows how much energy is retained in the form of new biomass at each trophic level. A number pyramid represents the number of individual organisms at each trophic level. Energy pyramids are typically upright, but other pyramids can be inverted or shaped differently.

Ecological pyramids start at the bottom with producers (such as plants) and work their way up through the various trophic levels (such as the herbivores that eat plants, then carnivores that eat flesh, than omnivores that eat both plants and flesh, and so). The top of the food chain is the highest level.

Ecological Pyramids

Famous scientists such as Charles Elton, G. Evelyn Hutchinson, and Raymond Lindeman contributed to the development of the ecological pyramid. It is also known as the Estonian pyramid after Charles Elton, the energy pyramid, the trophic pyramid, and the food pyramid.

The Ecological Pyramid is a graphical representation of the relationship between different living organisms at different trophic levels in an ecosystem. There are three types of ecological pyramids in an ecological pyramid.

Types of Ecological Pyramids

Pyramid of Numbers

The total number of individuals (population) present in each trophic level is represented by a pyramid of numbers. Elton coined the phrase “pyramid of numbers” in 1972. This pyramid is very useful, especially for counting the number of organisms. Counting is a simple task that can be repeated over time to determine changes in a specific ecosystem. Nonetheless, some organisms are difficult to count, particularly young forms.

The pyramid of numbers is divided into two types based on the number of organisms: upright and inverted.

The number of organisms decreases from bottom to top in the Upright Pyramid of Numbers. It is most common in pond and grassland ecosystems where plants occupy the pyramid’s base. Consumers are included in the pyramid’s subsequent levels.

An inverted pyramid is the inverse of an upright pyramid. It can be seen clearly in the tree ecosystem, where trees produce and insects consume.

Food waste during eating, food waste during digestion, and finally food use in the process of respiration and physical activities cause the population of higher tropic individuals to steadily decline.

Among three ecological pyramids. The number pyramid is the most incorrect because it does not take into account the exact population. As a result, it cannot fully elaborate on the trophic structure of a system.

This pyramid ignores species biomass and does not depict energy transfer between individual groups.

Number pyramids are ineffective because they do not provide a clear or accurate picture of the food chain.

They do not specifically indicate the absolute effects of the geometric, food chain, and size factors of specific organisms.

Pyramid of Biomass

Before we get into the biomass pyramid, it’s important to understand what biomass is. We can define biomass as the amount of living material present in an individual or a group of individuals at a specific trophic level expressed as a product per unit area.

This pyramid represents the total mass of organisms at a given trophic level. A number pyramid depicts the relationship between the amount of food available and the amount of energy passed at each trophic level. Animal biomass is mostly converted to living tissue, converted to energy, or remains as undigested products.

The pyramid is usually larger at the base, but as it rises, it shrinks and becomes smaller. With each trophic level increase, there is always a decrease in biomass. Approximately 10% to 20% of the biomass is passed from one trophic level to the next.

The biomass pyramid, like the number pyramids, has two forms: inverted and upright pyramids.

The aquatic ecosystem is characterised by an inverted pyramid because phytoplankton producers are at the bottom of the pyramid and consumers have higher biomass and are at the top.

The terrestrial ecosystem is an example of an upright pyramid. It has a large base that is mostly made up of primary consumers, with the smaller trophic levels at the top. So, how do we go about finding biomass? The biomass at a particular trophic level is calculated by multiplying the number of individuals within the trophic level by the average mass of an individual in a given area.

This pyramid can be used to solve the specific issue in the pyramid of numbers because it depicts the exact amount of energy present in each trophic level. When biomass decreases as trophic levels rise, it indicates wastage and biomass consumption at all transfer levels.

It also has some limitations, because measuring the mass of every single individual is impossible. Only a sample is taken, which leads to errors. Also, because breeding seasons differ between organisms, the specific time of year when data is collected should be considered.

Although biomass can sometimes indicate energy value, it does not show the amount of energy trapped at each energy level.

Pyramid of Energy

The energy pyramid is an upright pyramid that depicts the flow of energy from producers to consumers. It also indicates the actual role of various organisms in energy transfer. Energy pyramids show how much energy is required in the next trophic level as it rises.

The energy flow pattern in this pyramid can be described using the law of thermodynamics, which states that energy is neither created nor destroyed; it is only transformed from one form to another.

The rate at which food material (in the form of energy) passes through the food chain determines how energy pyramids are built. Although some of the organisms have lower biomass, the total energy they consume and pass on is significantly greater than that of organisms with higher biomass.

Energy pyramids typically slant because less energy is transferred from each trophic level than was placed into it. Consider open water communities, where producers have less bulk biomass than consumers. However, the energy stored and passed on should be greater than the previous level.

Thus, when describing the concept of biological magnification, the impression of the energy pyramid is critical. Biological magnification can be defined as the tendency of toxic substances to increase in quantity as you move up the trophic levels.

Ecological Pyramid Examples

The diagram below depicts an example of a productivity pyramid, also known as an energy pyramid. The sun is included in this diagram because it is the primary source of all energy, as are decomposers such as bacteria and fungi, which can obtain nutrients and energy from all trophic levels by breaking down dead or decaying organisms. 

We begin with the total amount of energy contained by the primary producers, which is denoted by 100 percent. As we progress through the levels, 90 percent of the energy is used for purposes other than the creation of flesh. The primary consumers end up with only 10% of the starting energy, and 10% of that 10% is lost during the transfer to the next level. This is one percent, and so on. The predators at the apex will thus receive only 0.01 percent of the initial energy Because of this system’s inefficiency, productivity pyramids are always upright.

The function of the Ecological Pyramid

An ecological pyramid not only shows the feeding patterns of organisms in various ecosystems, but it can also show how inefficient energy transfer is and the impact that a change in numbers at one trophic level can have on the trophic levels above and below it. Furthermore, when data is collected over time, the effects of environmental changes on organisms can be studied by comparing the data. If the conditions of an ecosystem are found to be deteriorating over time due to human pollution or overhunting, action can be taken to prevent further damage and possibly reverse some of the current damage.

Conclusion

Ecological pyramids start at the bottom with producers (such as plants) and work their way up through the various trophic levels (such as the herbivores that eat plants, then carnivores that eat flesh, than omnivores that eat both plants and flesh, and so). The Ecological Pyramid is a graphical representation of the relationship between different living organisms at different trophic levels in an ecosystem. This pyramid is very useful, especially for counting the number of organisms. Counting is a simple task that can be repeated over time to determine changes in a specific ecosystem. An inverted pyramid is the inverse of an upright pyramid. It can be seen clearly in the tree ecosystem, where trees produce and insects consume. The rate at which food material (in the form of energy) passes through the food chain determines how energy pyramids are built.