The ill effects of acidity in subsoils can be ameliorated by adding gypsum (CaSO 4 · 2H 2 O) to the soil surface. What are the mechanisms responsible for this effect of the gypsum? Compare the...

The ill effects of acidity in subsoils can be ameliorated by adding gypsum (CaSO₄
· 2H₂O) to the soil surface. What are the mechanisms responsible for this effect of the gypsum?

Compare the availability of the following essential elements in alkaline soils with that in acid soils: (1) iron, (2) nitrogen, (3) molybdenum, and (4) phosphorus.