The Wilcox Diagram is primarily used to evaluate which of the following characteristics?
- ASoil permeability
- BSuitability of water for irrigation based on salinity and sodium hazardCorrect
- CWater table fluctuations in aquifers
- DSediment transport in rivers
Solution
Concept
Irrigation water classification using Wilcox diagram
Formula
NONE
Step-by-step solution
1. A Wilcox diagram plots electrical conductivity against sodium absorption ratio (SAR) for irrigation water analysis. Answer: B
Explanation
The Wilcox diagram plots sodium adsorption ratio against electrical conductivity to classify water quality for agricultural use. This analysis assesses both salinity hazard and sodium hazard to ensure irrigation water will not harm crops or degrade soil structure. Thus, option B accurately describes the primary function of the Wilcox diagram.
Why the other options are wrong
A) Soil permeability is evaluated using permeameter tests or field pumping tests. D) Sediment transport in rivers is analyzed using bed-load and suspended-load transport equations.
Shortcut
Wilcox Diagram = Irrigation water suitability based on Sodium Hazard (SAR) and Salinity Hazard (EC).
Common mistake
Selecting option A or C by confusing the Wilcox Diagram with charts used for soil permeability or groundwater table analysis.
Correct answer: B) Suitability of water for irrigation based on salinity and sodium hazard