Ecological pyramids :These are graphic representation of certain specific parameters such as number, biomass or energy of a food chain. The pyramids of number and biomass are upright i.e., producers out number and out weigh the herbivores or herbivores out number or out weigh the carnivores.
However, in certain ecosystems, the pyramid of number (in tree dominated eco-system where number of insects is more) and biomass (in sea) is inverted.
In sea, the biomass of fishes far exceeds that of phytoplankton.
Upright Pyramid : In the upright pyramid, the base occupied by producers is broad as compared to subsequent consumers, which gradually narrow down at the apex. It occurs in all the three kinds of pyramids.
Inverted Pyramid : In the inverted pyramid, the base occupied by producer: is short as compared to subsequent consumers which gradually broaden at the apex. This gives the shape of inverted pyramid. It occurs in pyramid of biomass in sea.
