ecological pyramid

Fig. 141 Ecological pyramid . A hypothetical elcological pyramid for standing crop ontropical grassland. Figures in kcal m^-2yr^-1.

ecological pyramid

a graphical means of illustrating the trophic structure or trophic function of communities. They are of three general types:

1. the PYRAMID OF NUMBERS, which illustrates the numbers of organisms at each TROPHIC LEVEL (see Fig. 263 ).
2. the pyramid of BIOMASS, based on DRY WEIGHT (or occasionally live weight) at each level at a given time.
3. the pyramid of energy which shows the energy flow between each level. See FOOD CHAIN.