Pyramid of Number
• Pyramid of number deals with number of individuals in a trophic level.
• In Grassland ecosystem only 3 top carnivores are supported in an ecosystem based on production of nearly 6 million plants.
• Pyramid of number in grassland or forest or pond ecosystem is upright.
• In parasitic food chain, the pyramid of number is inverted.
• In an ecosystem dominated by trees the pyramid of number shaped/inverted.
• Among the grassland, pond and forest ecosystem, the number of primary producers per unit area would be maximum in pond ecosystem.
Pyramid of Biomass
• Total amount of living material at various trophic level of a food chain is depicted by pyramid of biomass.
In most of the ecosystem, the pyramids of number and biomass are upright.
• In terrestrial ecosystem pyramid of biomass is generally upright.
• The pyramid of biomass in sea or lake is generally inverted because the biomass of fishes for exceeds that of phytoplankton.