Correct option is A
Characteristics of Alkaline (Sodic) Soils:
ESP ≥15%
pH usually >8.5
Poor permeability and drainage due to sodium dispersing soil particles.
Hard crust formation and reduced plant growth.
Reduced availability of essential nutrients like calcium and magnesium.
Reclamation of Alkaline Soils:
Gypsum (CaSO₄·2H₂O) is used to replace sodium ions with calcium.
Sulfur and organic matter help improve soil structure.
Leaching with good-quality water removes excess sodium.
Difference Between Saline and Sodic Soils:
Saline soils have high soluble salts (EC >4 dS/m).
Saline-Sodic soils have both high ESP and high salts.