Question

Matric potential of saturated soil is

• A. Always negative
• B. Either positive and negative
• C. Always positive
• D. May be zero or negative

Hint:

Soil water potential components:
- Matric potential: Due to capillary/adsorptive forces.
- At saturation: Matric potential = 0 (or slightly negative).
- As soil dries: Matric potential becomes more negative.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
This question tests knowledge of soil water potential components.

Step 2: Detailed Explanation:
Matric potential is the potential due to capillary and adsorptive forces in the soil matrix.
In saturated soil, the matric potential is zero or slightly negative (D).
- At saturation: Matric potential is zero (all pores filled with water).
- Under tension: It becomes negative (as water is removed).
Other options:
- Always negative (A): Not true for saturated soil.
- Either positive and negative (B): Not correct.
- Always positive (C): Not correct.
Thus, matric potential of saturated soil may be zero or negative.

Step 3: Final Answer:
Thus, the matric potential of saturated soil may be zero or negative, which corresponds to option (D).
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