CBSE Class 12 Biology – Ecosystem

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Study Materials

12th

12th - Biology

Evolution

Chapter Overview

An ecosystem is a functional unit of nature: a community of living organisms interacting with non‑living (abiotic) components in a particular area. It can range from a pond to a forest to the global biosphere. Key processes include productivity, decomposition, energy flow, ecological pyramids, succession, and nutrient cycling. :contentReference[oaicite:0]{index=0}

Important Keywords

  • Biotic components: Producers, consumers, decomposers.
  • Abiotic components: Non‑living environment—soil, water, air, light.
  • Productivity: Rate of biomass production; includes GPP and NPP.
  • Decomposition: Breakdown of organic matter to inorganic nutrients.
  • Food chain/web: Pathways of energy from producers to consumers/decomposers.
  • Ecological pyramids: Numbers, biomass, energy pyramids across trophic levels.
  • Succession: Sequential change in ecosystem structure—primary vs secondary.
  • Nutrient cycling: Recycling of essential elements like carbon, nitrogen, phosphorus.

Detailed Notes

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