How does irrigation through multi-purpose projects lead to the problem of salinisation of soil? Name the cropping change that contributes to this.
Generated by claude-sonnet-4-6 · 2026-06-26 13:31 · grounding rag
Model Answer
When irrigation water is oversupplied through canals from multi-purpose projects, it raises the water table. As this water moves upward through capillary action, it brings dissolved salts to the surface, leading to salinisation of the soil, which makes it infertile.
The cropping change responsible is the shift to water-intensive and commercial crops by farmers in irrigated regions.
Source: Water Resources, Multi-Purpose River Projects and Integrated Water Resources Management
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Explanation
- Two points are needed for 2 marks: (1) the mechanism of salinisation, and (2) the name of the cropping change.
- The textbook states directly: "Irrigation has also changed the cropping pattern of many regions with farmers shifting to water intensive and commercial crops. This has great ecological consequences like salinisation of the soil."
- Mention capillary action / rising water table → salt deposition — this shows understanding of the process.
- Do not write about waterlogging as a separate issue; keep focus on salinisation as asked.