Which of the following soil types, locally known as 'Regur' or black cotton soil, covers extensive areas of the Deccan plateau and is characterized by high moisture-retention capacity and self-ploughing properties due to swelling clays?

💡 Solution & Explanation

Black soils, derived from volcanic basaltic parent rock across the Deccan trap region, are rich in lime, iron, magnesia, and alumina, exhibiting high clay content dominated by montmorillonite minerals that expand when wet and shrink to form deep cracks when dry. Laterite soils develop in areas with high temperature and heavy alternating rainfall through intense leaching, whereas alluvial soils are transported deposits found extensively in northern river plains.