In situ calibration of two FDR gauges under saline soil conditions in the hyperarid of Chile

• Cristián Kremer Fariña Coll. Agronomic Scs, University of Chile, Santa Rosa 11315, La Pintana, Santiago, Chile. Postal code 8820808
• Rodrigo Candia Antich Coll. Agronomic Scs, University of Chile, Santa Rosa 11315, La Pintana, Santiago, Chile. Postal code 8820808 https://orcid.org/0000-0001-8063-6903
• Ian Homer Bannister Coll. Agronomic Scs, University of Chile, Santa Rosa 11315, La Pintana, Santiago, Chile. Postal code 8820808 https://orcid.org/0000-0002-3918-5765
• Oscar Seguel Seguel Coll. Agronomic Scs, University of Chile, Santa Rosa 11315, La Pintana, Santiago, Chile. Postal code 8820808 https://orcid.org/0000-0001-7040-3604

Palabras clave: contenido de agua del suelo, permisividad dieléctrica, salinidad del suelo, constante dieléctrica

Resumen

A calibration method was developed for two FDR sensors (GS3 and POGO) in saline soil conditions with predominantly fine textures and electrical conductivities that fluctuate between 4.4 and 16.5 dS.m^-1. The methodology included the use of infiltration trenches and the recording of the variation of the water content (Ɵ) over time. The results showed that there is an overestimation of Ɵ as a function of the salt content. The standard error obtained with the manufacturer's calibration was 0.09 and 0.19 cm³.cm^-3 for GS3 and POGO, respectively. After calibration, the standard error decreased to 0.04 and 0.05 cm³.cm^-3, respectively. The R² of the calibration equations for GS3 and POGO were 0.94 and 0.86 respectively, not being necessary a differentiated calibration by salinity ranges. The GS3 sensor performed better than the POGO in the salinity conditions encountered.

Citas

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