Question

Arrange the following factors affecting irrigation water quality in agriculture in the correct sequence:
(A) Salinity
(B) pH
(C) Sediment content
(D) Chemical contaminants

• A. (A), (B), (C), (D)
• B. (A), (C), (D), (B)
• C. (B), (A), (D), (C)
• D. (C), (B), (D), (A)

Hint:

Assess water quality by salinity, pH, sediment, then chemical contaminants.

Answer 1

The Correct Option is A

The correct order is: Salinity (affects osmotic potential), pH (influences nutrient availability), Sediment (clogs equipment), and chemical contaminants (toxic effects).

Answer 2

Alternate approach — Priority of assessment:
Irrigation water is conventionally evaluated by assessing its dominant physiological and physical hazards in order of the severity of their impact on crops and infrastructure. Salinity (total dissolved salts) is assessed first because it directly affects the osmotic potential available to plant roots and can cause immediate crop stress. pH is checked next since it governs nutrient solubility and availability once the water is applied. Sediment content is examined next as it primarily affects irrigation equipment, such as clogging drippers and sprinklers, rather than the crop directly. Chemical contaminants (heavy metals, pesticide residues, etc.) are typically assessed last as a specialised, situation-specific hazard.
Ranking the four factors by how fundamentally and immediately they affect crop growth and irrigation system performance reproduces the sequence Salinity, pH, Sediment content, Chemical contaminants, confirming option (A), (B), (C), (D).