Question

Biological measures for soil erosion is

• A. Strip cropping
• B. Bench terracing
• C. Contour bench terracing
• D. Broad base terrace

Hint:

Remember the classification:
Biological (Agronomic) measures: Strip cropping, mulching, contour farming, cover crops.
Engineering (Mechanical) measures: Terraces, bunds, check dams, gully plugs.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Soil conservation measures to control water and wind erosion are classified as biological (agronomic) measures or engineering (mechanical/structural) measures.
Biological measures use vegetation and cropping practices to protect the soil surface and reduce runoff velocity, while engineering measures use physical structures to control water flow.

Step 2: Detailed Explanation:
Let us analyze the conservation measures listed in the options:
1. Strip cropping: Is an agronomic/biological measure where erosion-resisting crops (such as dense, ground-covering legumes like groundnut or cowpea) are grown in alternate strips with erosion-permitting crops (such as row-planted cereals like maize or jowar).
The dense canopy of the erosion-resisting strips intercepts raindrops, reduces their kinetic energy, and slows down surface runoff, protecting the soil from erosion.
2. Bench terracing, Contour bench terracing, and Broad-base terraces: Are engineering or mechanical measures.
These structures require soil excavation and grading to construct physical steps or embankments across the slope.
These physical barriers break the length of the slope and intercept runoff water, reducing soil loss on steep terrains.
Because strip cropping relies on vegetation and cropping patterns rather than physical structures, it is classified as a biological measure.

Step 3: Final Answer:
The biological measure for soil erosion is Strip cropping, which corresponds to Option (A).