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Ecosystems — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYEcosystems5 Marks
Question
What are ecological pyramids? Mention its limitations.
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Answer

An ecological pyramid is a graphic representation of an ecological parameter like number of individuals present in various trophic levels of a food chain with producers forming the base and top carnivores forming the tip.There are three types of ecological pyramids:
  1. Pyramid of numbers.
  2. Pyramid of biomass.
  3. Pyramid of energy.
Limitations:
  1. It assumes that food chains are simple. Simple food chains do not occur in nature. Instead food webs are present.
  2. A simple species may operate at two or more trophic levels. Ecological pyramids have no method of accommodating such cases.

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