Ecological Pyramid

All About Different types of Ecological pyramid

1. Ecological Pyramids A Key To Understanding The Structure And Function Of Ecosystems

2. Vadodara Institute Of Engineering Environmental Studies - Prof. Dayanjali Thakkar Jay Bhosle [ 17MECH013 ] Shethwala Mohd Shafi M.Shoeb [17mech014 ] Jayesh Nakiya [ 17MECH015 ]

3. Contents……. What are Ecological Pyramids ? Types of Ecological Pyramid Pyramid of numbers Pyramid of Numbers - Example Pyramid of Biomass Inverted Pyramid of Biomass Pyramid of Productivity Bioaccumulation Bio-magnification

4. What are Ecological Pyramids ? Ecological pyramids are graphical representation of the trophic of the trophic structure of ecosystem. Trophic Levels are the feeding position in a food chain such as primary producers, herbivore, primary carnivore, etc.

5. Types of Ecological Pyramid Three types of ecological pyramid can usually be distinguished namely :- 1 ) Pyramid of Numbers 2 ) Pyramid of Biomass 3 ) Pyramid of Productivity

6. # Pyramid of numbers Is The Graphic Representation Of Number Of Individuals Per Unit Area Of Various Trophic Levels. Large Numbers Of Producers Tend To Form The Base. Lower Numbers Of Top Carnivores Occupy The Tip.

7. Evaluation of Pyramid of Number ADVANTAGES Simple easy method (number counting) of giving an overview Good for comparing changes to the ecosystem at different times of year e between seasons DISADVANTAGES Numbers of a specific species can be too great to measure accurately Does not take into account juveniles' or immature forms All organisms are included regardless of size, hence inverted pyramids

8. Pyramid of Numbers - Example The shape of the pyramid of numbers vary from ecosystem to ecosystem. In aquatic ecosystems and grassland communities, autotrophs are present in large numbers per unit area. They support a lesser number of herbivores, which in turn support fewer carnivores.

9. Evaluation A Pyramid Of Bio-mass ADVANTAGES Overcomes the problems of Pyramids of number DISADVANTAGES Only uses samples from populations, so difficult to measure biomass exactly. Time of year that biomass is measured influences result e.g. trees in summer. Organisms of the same size do not necessarily have the same energy Content

10. Pyramid of Biomass Is the graphic representation of biomass present per unit area of different trophic levels , with producers at the base and top carnivores at the tip. Biomass is calculated by the mass of each individual x number of individuals at each trophic level.

11. Inverted Pyramid of Biomass In an aquatic habitat the Pyramid of biomass is inverted or spindle shaped where the biomass of trophic level depends upon the reproductive potential and longevity of the members

12. Pyramid of Productivity Pyramid Of Productivity Is A Graphic Representation Of The Flow Of Energy Through Each Trophic Level Of A Food Chain Over A Fixed Time Period. The Input Of Solar Energy May Be Indicated As An Extra Layer At The Base.

13. Only 10% of the energy is available to next trophic level ( as per Lindeman's ten percent rule)

14. Pyramid of productivity Advantages No inverted pyramids are obtained. Shows actual energy transferred and allows for rate of production Disadvantages It is difficult and complex to collect energy data (rate of biomass production over time). Problem always exists in assigning a species to a specific trophic level.

15. Bioaccumulation :- when plants animals take up a chemical from the environment and do not excrete it The chemical builds up in the organism over time to a potentially lethal level. Consequences of Ecological Pyramids and Ecosystem function

16. Bio-magnification :- refers to the sequence of processes that results in higher concentrations of the chemical in organisms at higher levels in the food chain (at higher trophic levels). In this way the chemicals concentration is magnified from trophic level to trophic level. The concentration of the chemical may not affect lower levels of the food chain but the top levels take in so much it can cause disease or death. Consequences of Ecological Pyramids and Ecosystem function

17. There are many pollutants like the DDT that are not bio- degradable. These accumulate in the organisms and cause serious health problems. The contamination of water with these pollutants results in their entry into the microscopic plants and animals. These organisms are fed upon by higher aquatic life like the fish . The fish in turn are fed upon by the land animals including man. Thus, the pollutant reaches the body of man. At each step in the food chain, the contaminant increases in quantity. This is because a fish feeds on large quantity of smaller plants and man eats fish. These contaminants like DDT remain in the fats and are not degraded in the body. Over the years the amount of DDT increases in the body. This is called bio-magnification.