Question

Working range of tensiometer for determination of soil moisture is

• A. 0 - 15 bar
• B. 0 - 0.8 bar
• C. 0.8 - 15 bar
• D. 0 - 0.3 bar

Hint:

Tensiometer:
- Measures soil moisture tension (0-0.8 bar).
- Used for irrigation scheduling.
- Beyond 0.8 bar, other methods (e.g., gypsum blocks) are used.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
This question tests knowledge of the tensiometer, an instrument used for measuring soil moisture.

Step 2: Detailed Explanation:
A tensiometer is used to measure soil moisture tension (matric potential) in the range of 0 to 0.8 bar (B).
It is effective for measuring soil moisture in the field capacity range (0 to -0.8 bar).
Beyond 0.8 bar, the soil becomes too dry and the tensiometer no longer works effectively (air entry occurs).
Other ranges:
- 0 - 15 bar (A): This is the range of plant available water (not the working range of a tensiometer).
- 0.8 - 15 bar (C): This is the wilting range (not measured by tensiometer).
- 0 - 0.3 bar (D): Too narrow.
Thus, the working range of a tensiometer is 0 - 0.8 bar.

Step 3: Final Answer:
Thus, the working range of a tensiometer is 0 - 0.8 bar, which corresponds to option (B).
[0.5cm]