Diagrams of an ecological pyramid are used to display the biomass or bioproductivity at each trophic level in a given ecosystem. In a pyramid of energy, the amount of energy retained in the form of new biomass at each trophic level is shown, whereas in a pyramid of biomass, the amount of biomass (or the amount of living or organic matter present in an organism) is shown in the organisms. In addition, a pyramid of numbers represents the number of individual organisms at each trophic level, with the numbers increasing as you progress up the pyramid. Pyramids of energy are typically upright structures, but they can also be inverted or take on other shapes as well.
Ecological Pyramids
Ecological pyramids begin with producers at the bottom (such as plants) and work their way up through the various trophic levels to the top (such as herbivores that eat plants, then carnivores that eat flesh, then omnivores that eat both plants and flesh, and so on). The apex of the food chain represents the highest level.
What exactly is the Ecological Pyramid?
Essentially, an ecological pyramid depicts the relationship between different living organisms belonging to different trophic levels. G.Evelyn Hutchinson and Raymond Lindeman were the ones who delivered the speech.
In this case, it can be seen that these pyramids are in the shape of actual pyramids, with the base being the broadest and being covered by the lowest trophic level, that is, producers, at the bottom. The following trophic level, i.e., the primary consumers, takes up residence on the following level, and so on.
In order to construct these types of ecological pyramids, all calculations must take into account all of the organisms in a given trophic level, because a sample space consisting of only a few numbers or only a few species will result in a high level of error.
Types of Ecological Pyramid
There are three different types of ecological pyramids. The names of these are as follows:
Pyramid of Numbers
A level in this type of ecological pyramid is determined by the number of organisms found in each trophic level, which corresponds to the number of levels in the pyramid. With the exception of some situations such as the detritus food chain, in which a large number of organisms feed on a single dead plant or animal, the pyramid of numbers is usually upright.
Pyramid of Biomass
A particular type of ecological pyramid is one in which each trophic level’s contribution to total biomass production is taken into consideration at each level. The pyramid of biomass is also upright, with the exception of the one observed in oceans, where large numbers of zooplanktons are dependent on a relatively small number of phytoplanktons for their survival and reproduction.
Pyramid of energy
In a pyramid of energy or a pyramid of productivity, the amount of biomass produced or the rate at which energy or mass is transferred from one trophic level to the next is represented by the shapes of the pyramids of energy and productivity. Instead of depicting a single point in time, productivity pyramids depict the movement of energy through the food chain. Grams per square metre per year or calories per square metre per year are two common units of measurement. This graph, like the others, shows producers at the bottom of the graph and higher trophic levels at the top.
Due to the fact that, in order for an ecosystem to survive, there must be more energy available at lower trophic levels than there is available at higher trophic levels, this is true. This enables organisms on the lower levels of the pyramid to not only maintain a stable population, but also to transfer energy upwards through the pyramid. If there is an exception to this rule, it is when portions of a food web are supported by inputs of resources from sources other than the immediate local environment. For example, in small, forested streams, the volume of higher levels is greater than the amount of primary production that could be supported by the local ecosystem.
The majority of the energy that enters ecosystems comes from the Sun. Solar radiation is used by the primary producers at the base of the pyramid to power photosynthesis, which results in the production of food. However, because the majority of solar radiation’s wavelengths are ineffective for photosynthesis, they are reflected back into space or absorbed and converted to heat in other locations. Only 1 to 2 percent of the energy emitted by the sun is absorbed by photosynthetic processes and used to produce food in plants. When energy is transferred to higher trophic levels, only about ten percent of the energy transferred is used to build biomass at each level, resulting in stored energy being created. The remaining energy is used for metabolic processes such as growth, respiration, and reproduction, among others.
Limitations of Ecological Pyramids
- As in the case of the food web, more than one species may occupy different trophic levels at the same time. As a result, this system does not take into consideration food webs.
- The saprophytes are not taken into consideration in any of the pyramids, despite the fact that they are an important component of the different ecosystems.
- These pyramids are only applicable to simple food chains, which are not typically found in nature.
- In terms of seasonal and climatic variations, these pyramids provide no information.
- They do not take into consideration the possibility of the same species existing at different levels of evolution.
Conclusion
Essentially, an ecological pyramid depicts the relationship between different living organisms belonging to different trophic levels. G.Evelyn Hutchinson and Raymond Lindeman were the ones who delivered the speech. In this case, it can be seen that these pyramids are in the shape of actual pyramids, with the base being the broadest and being covered by the lowest trophic level, that is, producers, at the bottom. The following trophic level, i.e., the primary consumers, takes up residence on the following level, and so on.