Ecological pyramid

An ecological pyramid is a graphical representation designed to show the biomass or bio-productivity at each trophic level in a given ecosystem. there are three types of pyramid- 1) Pyramid of number.2) Pyramid of biomass 3) Pyramid of energy.

1. ECOLOGICAL PYRAMID Presented by- Vandana Singh Msc 1 st sem

2. Contents 1 . Definition of Pyramids 2. Types of Pyramid a) Pyramids of numbers b) Pyramids of biomass c) Pyramids of energy 3. Importance of Pyramids 4. Limitations of Pyramids 5. References

3. DEFENITION OF PYRAMID An ecological pyramid is a graphical representation designed to show the biomass or bio-productivity at each trophic level in a given ecosystem. Charles Elton (1927) developed the idea of ecological pyramids. Therefore these are also termed as Eltonian pyramids.

4. TYPES OF PYRAMID Pyramid of number Pyramid of biomass Pyramid of energy

5. PYRAMID OF NUMBER Definition – the number of organisms in a food chain can be represented graphically in a pyramid. Each bar represents the number of individuals at each trophic level in the food chain. It can be upright and inverted.

6. Upright pyramid Inverted pyramid

7. PYRAMID OF BIOMASS Definition – The pyramid of biomass is a graphical representation that depicts the biomass existent in per unit area in all the different trophic level of the ecological system. It can be upright and inverted.

8. Upright pyramid Inverted pyramid

9. PYRAMID OF ENERGY Definition- An energy pyramid is a graphical model of energy flow in a community. The different level represent different group of organism that might composed of food chain. Pyramid of energy is always upright as it follows the second law of thermodynamics which states that as energy is transferred or transformed, more and more of it wasted.

10. Upright model of pyramid of energy

11. IMPORTANCE OF ECOLOGICAL PYRAMIDS Easy to understand. It gives overall picture of transfer of energy from one trophic level to the next.

12. LIMITATIONS OF ECOLOGICAL PYRAMIDS It assumes a simple food chain, something that almost never exist in nature. It does not consider a food web. It does not take into account the same species belonging to two or more trophic level.

13. REFERENCES P.S. D hami , G. Chopra, H.N. Srivastava , A Text Book Of Biology S.K. Agarwal , Fundamentals Of Ecology www.wikipedia.com

14. THANK YOU