Ecological Pyramids | Trophic pyramid | Pyramid of Numbers | Pyramid of Biomass | Pyramid of Energy
This video explains the Ecological Pyramids or Trophic pyramid, Pyramid of Numbers, Pyramid of Biomass, and Pyramid of Energy.
An ecological pyramid is a graphical representation of the relationship between organisms within a trophic level in an ecosystem. Here, two words are important: Relationship and Trophic Level of organisms in the ecosystem.
In ecological pyramid, the trophic levels are represented by successive polygonal bases. So, each trophic level is related to successive base of the pyramid from bottom to the apex. Usually, Primary producers are represented by the bottom base of the pyramid. Primary consumers are represented by the next base of the polygon and so on. The top area of the pyramid represents the Top predators.
Generally, three basic relationships are used for Ecological pyramids. And they are Numbers, Biomass and Energy. Accordingly, ecological pyramids are classified as:
Pyramid of Numbers, Pyramid of Biomass, and Pyramid of Energy. Ecological pyramids are prepared based on number of organisms, biomass of the organisms, and energy in the biomass of organisms in each trophic level.
Pyramid of Numbers:
If the Number of organisms of Primary producers are more, the area of the polygon will be more. Accordingly, the area of the graph will go on decreasing towards top and we get the shape of a pyramid.
In a forest ecosystem the number of producers is highest. The number decreases in herbivore level. And the population decreases at each successive trophic level. Least population is in Top Carnivore level.
Pyramid of Energy:
A pyramid of energy shows the total quantity of available energy stored in the biomass of organisms at each level in the food chain of an ecosystem. In Forest ecosystem, 10 percent of Energy flows to the successive higher trophic levels. So, 100 units of energy in producer level goes on depleting and is 10 unit at the secondary consumer level.
The energy flow is similar in aquatic ecosystem. The amount of energy decreases form 10000 kilo Joule in producer level to 1000 kilo joule in primary consumer level. This is called the 10 percent rule. That means the only 10 percent of the energy is transferred to the next higher trophic level.
An ecological pyramid shows how efficiently energy is transferred from one level to the other and also helps to quantify energy in a food chain. This pyramid also shows how various organisms in various ecosystems feed on each other, highlights their food patterns and explains the relationship between the various levels within it. The ecological pyramid also helps in monitoring the overall health and condition of an ecosystem. It also helps to understand how any further damage to an ecosystem can be prevented.