Department of Power and Machinery, Faculty of Agriculture, University of Tehran, Karaj, Islamic Republic
of Iran.
Abstract: (5671 Views)
To measure soil water content (or soil matric suction) in thin layers of about 30mm,
conventional gypsum blocks are not suitable. To carry out the task, mini-gypsum blocks
were constructed using plaster of Paris in an innovative fashion. A power relationship was
found between the soil water content and the mini-gypsum blocks’ readings in kΩ. The
calibration results showed that readings of mini-gypsum blocks were sensitive to temperature.
A normalized resistance deviation method was adopted to compensate for the effect
of temperature on the sensor readings. After calibration, the high coefficient of determination
obtained ensured the use of the mini-gypsum blocks for further experiments.
Subject:
Soil Science Received: 2010/05/16 | Accepted: 2010/05/16 | Published: 2010/05/16