EVALUATION OF THE DECAGON® 5TE SENSOR AS A TOOL FOR IRRIGATION AND SALINITY MANAGEMENT IN A SANDY SOIL
Near-continuous and near-real-time measurement of soil water content is a valuable tool in irrigation management. The Decagon® 5TE is a recently available sensor that simultaneously measures soil water content, bulk soil electrical conductivity, and temperature, and so could be useful under saline conditions. Initial laboratory and field studies were conducted at the International Center for Biosaline Agriculture (ICBA) in Dubai, United Arab Emirates. A sample of four sensors was evaluated in the laboratory under different soil water contents and salinities. In the field, sensors were installed at depths of 10, 30 and 50 cm in the soil in various plots as part of ongoing water productivity experiments that used relatively low (2 dS m-1) and high (8+ dS m-1) salinity irrigation water. The bulk soil electrical conductivity was used to estimate soil pore water conductivity. Results show that the sensors responded well, in a relative sense, to changes in soil water content, electrical conductivity and temperature, and so could be used to assess irrigation events, infiltration, and drainage. Water with conductivity in excess of 10 dS m-1 resulted in increased soil water content measurements due to the effect of electrical conductivity on measured dielectric permittivity. Estimates of soil water salinity followed expected patterns, with lower values directly following irrigation and higher values as soil water content decreased due to plant water uptake.
McCann, I.R., Fraj, M.B. and Dakheel, A. (2014). EVALUATION OF THE DECAGON® 5TE SENSOR AS A TOOL FOR IRRIGATION AND SALINITY MANAGEMENT IN A SANDY SOIL. Acta Hortic. 1054, 153-160
sensor, near-continuous, soil water, conductivity, temperature