释义 |
ecological pyramid
ecological pyramid[ek·ə′läj·ə·kəl ′pir·ə·mid] (ecology) A pyramid-shaped diagram representing quantitatively the numbers of organisms, energy relationships, and biomass of an ecosystem; numbers are high for the lowest trophic levels (plants) and low for the highest trophic level (carnivores). 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: - the PYRAMID OF NUMBERS, which illustrates the numbers of organisms at each TROPHIC LEVEL (see Fig. 263 ).
- the pyramid of BIOMASS, based on DRY WEIGHT (or occasionally live weight) at each level at a given time.
- the pyramid of energy which shows the energy flow between each level. See FOOD CHAIN.
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