Q1. It has been found recently that the acidity of the soil increases because of
(a) Leaching away of bases
(b) Increased use of ammonia
(c) Increased use of urea
(d) Increased use of rock phosphate
(UPSC Prelims 1979)
Answer: (a) Leaching away of bases
Explanation: Soil acidity rises when basic nutrients like calcium and magnesium are leached away due to heavy rainfall or irrigation, leaving behind acidic residues. This affects crop productivity and soil health.