The diagram illustrates a pH scale.
(a) Comment on the pH status of a sample of soil as indicated by the reading of the pointer.
(b) State three factors responsible for alkalinity in the soil.
(c) Mention three factors responsible for acidity in the soil
(d) State two corrective measures of removing alkalinity in the soil.
(e) List five liming materials.
Explanation
(a) The pH status as indicated by the pointer reads 5.0 which indicates that the soil is slightly acidic.
(b) Factors responsible for the alkalinity in the soil are:
- concentration of soluble salts in the soil
- Lack of rainfall
- use of acid-fertilizers.
(c) Factors responsible for the acidity in the soil are:
- leaching
- use of acid fertilizers
- presence of acid parent materials
- Nutrient uptake by plants
- presence of sulphur in the soil
(d) Alkalinity in the soil can be removed by:
- use of acid fertilizers
- application of sulphur to the soil
- irrigation.
(e) Liming materias are;
- limestone
- slaked lime
- Quicklime
- wood ash
- Calcium hydrogen carbonate.