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Social Science (087) — AI-generated practice question

AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.

Q1. [3] deep thorough-understanding
A dam constructed on a river creates a large reservoir on what was previously a floodplain. Identify TWO distinct environmental problems that arise specifically because of this submergence, and explain the long-term consequence of each.
Generated by claude-sonnet-4-6 · 2026-06-26 13:31 · grounding rag
Model Answer

Two environmental problems caused by submergence of floodplains due to dam construction:

  1. Loss of vegetation and soil decomposition: The reservoir submerges existing vegetation and soil. Over time, this organic matter decomposes, releasing greenhouse gases and depleting soil fertility permanently in that region.
  1. Deprivation of silt on floodplains: Sedimentation collects at the reservoir bottom, preventing nutrient-rich silt from reaching downstream floodplains. Long-term consequence is land degradation and reduced agricultural fertility of downstream areas.

Source: Multi-Purpose River Projects and Integrated Water Resources Management, Chapter 3

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Explanation

The question asks for problems specifically from submergence — not general dam problems. The textbook directly mentions (a) submerged vegetation decomposing and (b) silt being trapped in reservoirs, depriving floodplains of natural fertiliser. Examiners expect you to name the problem clearly and then state its long-term consequence — two distinct parts per point. Avoid vague answers like "harms nature"; be specific as the textbook is.

Previous-year CBSE Grade 10 board exam questions, organised by subject and chapter, each with a model answer — free to read and print.