Previous Year Question
Contour bunding is a method of soil conservation used in
desert margins, liable to strong wind action
low flat plains, close to stream courses, liable to flooding
scrub lands, liable to spread of weed growth
none of the above
Correct Answer: D
Detailed Solution
In contour bunding, earthen or stone bunds are constructed approximately parallel to contour lines, which join points of equal elevation on sloping land.
These bunds obstruct rainwater flowing down the slope, reduce the speed and volume of surface runoff and provide more time for water to infiltrate the soil.
A reduction in runoff velocity decreases the erosion of fertile topsoil. This method is therefore primarily employed for soil and water conservation on sloping agricultural land.
Windbreaks or shelterbelts are more appropriate for desert margins affected by wind erosion, as described in option (a).
Low, flat and flood-prone plains in option (b) require flood-control embankments and drainage arrangements. The spread of weeds described in option (c) is a vegetation-management problem.
None of the options mentions sloping land. Therefore, the correct answer is none of the above.