Calibration of Soil Moisture Probes in Saline Conditions


Two soil moisture probes from Decagon Devices were calibrated to measure volumetric water content and salt concentration in the soil's moisture. The probes used were the EC-5 and EC-10 models, and the soil used has a USCS classification of SP or poorly graded sand. The EC-10 probes were found to work well for determining the salt concentration, in parts per million, of the soil if the volumetric water content is already known. The EC-5 probes also proved useful for the determination of salt concentrations, but the EC-10 probes proved to be more accurate. Soil-specific calibration curves were developed for both probes for use in saline soils at a range of volumetric moisture contents. Both probes were found to be useful for determining the volumetric water content of soils with no salt present. The probes have each have a very similar calibration curve in non-saline soils so a single curve was developed for both the EC-5 and EC-10.


Civil, Architectural and Environmental Engineering

Keywords and Phrases

Soil Water; Water Content; Calibration; Moisture; Salinity

Document Type

Article - Conference proceedings

Document Version


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© 2007 American Society of Civil Engineers (ASCE), All rights reserved.

Publication Date

01 Jan 2007