Laboratory evaluation of dual-frequency multisensor capacitance probes to monitor soil water and salinity

Content Provider	Semantic Scholar
Author	Starr, Jefferey L. Timlin, Dennis J. Downey, Peter M. McCann, Ian
Copyright Year	2009
Abstract	Real-time information on salinity levels and transport of fertilizers are generally missing from soil profile knowledge bases. A dual-frequency multisensor capacitance probe (MCP) is now commercially available, for sandy soils, to simultaneously monitor volumetric soil water content (VWC) measured as a percentage and salinity as a unitless volumetric ion content (VIC). The objectives of this research were to assess the relationship of salinity and water content with these dual-frequency MCPs under laboratory conditions, and assess its potential for field use in sandy soils of the mid-Atlantic region of the US. Water and salinity studies were conducted in two sand-filled PVC columns, 1.2 m long by 0.25 m ID. Each column was instrumented with ten dual-frequency capacitance sensors and two thermocouple temperature sensors. Four salinity levels were studied in the two columns using 0.5, 1, 2, and 4 dSm−1 NH4NO3 solutions. Water, salinity, and temperature readings were continuously recorded at 1-min intervals. The VIC values were found to be primarily qualitative, but combined with real-time VWC measures the probe could still be an important fertigation management tool to provide near-continuous real-time information on fertilizer penetration, spread and subsequent changes during crop growth.
Starting Page	393
Ending Page	400
Page Count	8
File Format	PDF HTM / HTML
DOI	10.1007/s00271-009-0154-3
Volume Number	27
Alternate Webpage(s)	https://naldc.nal.usda.gov/download/36012/PDF
Alternate Webpage(s)	https://doi.org/10.1007/s00271-009-0154-3
Journal	Irrigation Science
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article