Researchers from the University of Connecticut (UConn) have developed a soil moisture sensor that is more economical than anything presently available and offers a solution to the universal need to control water consumption in agriculture.
Developed and tested on UConn’s farm, the sensors are sufficiently small to be inserted into the soil without much effort and less expensive to make than existing technology, the scientists observe in the Journal of Sensors and Actuators.
Advances in hydrological science are hampered by the lack of on site soil moisture data. It’s really hard to monitor and measure things underground. The challenge is that the existing sensors are very expensive and the installation process is very labor intensive.
Guiling Wang, Study Author and Professor of Civil and Environmental Engineering, University of Connecticut
The sensors built by the team of UConn engineers—mechanical, environmental, and chemical—are estimated to save approximately 35% of water consumption and cost a lot less than what is presently available. The scientists stated that existing sensors that are used in a comparable way range from $100 to $1,000 each, while the one built at UConn costs $2.
An alternate monitoring option is to collect soil moisture data from remote sensing technology such as radiometers on board satellites and radars. However, these have suffered from low resolution. But the new technology created by UConn Professor Baikun Li’s group can offer high spatio-temporal resolution data required for hydrology model development in Wang’s group.
In the UConn model, wires are connected from the sensors to an instrument that records data. Scientists carried out field tests of the sensors—conducting continuous tests with commercial sensors under different environmental conditions spanning a 10-month period. The effects of the environmental differences on soil moisture across the period were noticeably reflected.
Critically, the small sensors can also be easily transported globally because soil moisture has a central role to play in agricultural decision-making worldwide.
Precise soil moisture sensing is crucial to ensure water level produces very sturdy crops while not wasting the natural resource. In certain states in the United States—Florida and California, for instance—irrigation water usage has become stringently controlled.
The UConn scientists are also involved in building a nitrogen sensor that is the same model of the water sensors. These would help offer farmers with data on when fields require fertilizing. At present, nitrogen sensors based on this type of technology are not available.
This is really an exciting start to a much larger scope of things we have in mind.
Baikun Li, Study Author and Professor of Civil and Environmental Engineering, University of Connecticut