Q1. [3] deep thorough-understanding
India's rural households are being encouraged to shift from burning firewood and cattle dung cakes to using biogas plants. Explain how this single change can produce two agricultural and two environmental benefits simultaneously.
Generated by claude-sonnet-4-6 · 2026-06-26 13:34 · grounding rag
Model Answer
Shifting to biogas plants provides the following benefits:
Agricultural Benefits:
- The slurry left after biogas production is improved quality manure, which enriches soil fertility better than raw dung.
- Since dung is no longer burned, the full nutritive value of cattle waste is available for use as fertiliser in fields.
Environmental Benefits:
- Reduced burning of firewood conserves forest cover and prevents deforestation.
- Less burning of dung cakes and firewood means reduced air pollution and lower release of harmful gases.
Source: Non-Conventional Sources of Energy, Chapter 5
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Explanation
- The passage explicitly states biogas gives "twin benefits: energy and improved quality of manure" — use this phrase.
- The key agricultural point is that burning dung destroys manure value; biogas preserves it AND improves it.
- Environmental benefits come from not burning: forests are saved and air pollution is reduced.
- For 3 marks, examiners expect 2 agricultural + 2 environmental points clearly labelled — don't just list vaguely. Four crisp points is the right structure here.