Introduction
- Ecological Pyramids are graphical representation of structure & function of ecosystem at trophic levels.
- First described by Charles Elton, hence, also called Elton Pyramids.
- Show relative amounts of parameters like number, energy, biomass etc. across trophic levels.
- First trophic level/Producer forms the base.
- Successive trophic levels are represented by tiers above the base.
1) Pyramids of Number:
- Represent number of individual organisms per unit area at each trophic level.
- It can be either upright (Figure 1) or inverted (Figure 2), depending on type of ecosystem.
2) Pyramids of Biomass:
- Represent amount of energy converted into living tissue at different trophic levels.
- It can also be either upright (Figure 3) or inverted (Figure 4), depending on type of ecosystem.
3) Pyramid of Energy:
- Represent energy flow through trophic levels (Figure 5).
- Always upright.
- An ecosystem without sufficient primary productivity cannot be supported.
