Calibração em laboratório de sensores fdr (frequency domain reflectometry) para medição da umidade do solo.

Abstract

The determination of soil water content is an essential data for soil and water management, irrigation, drainage, and monitoring of water and solute movement into the soil profile. Actually, there is a number of equipment for determination of soil moisture content and they work according to different principles. But, they usually estimates the water content based on a given soil property that follows the variation of water content. Thus, the objective of this work was to calibrate an FDR sensor model Sentry 200 AP. The calibration followed an exponential model e it showed high correlation between sensor reading and gravimetric moisture, in all depths (10, 30, 50, 70, 90, 110 cm) of the profile of a soil from the Costal Tablelands of Bahia. The determination coefficient varied from 0.937 (70 cm) to 0,996 (90 cm). The calibration procedure here adopted revealed to be appropriate for this type of sensor when it has to be used under filed conditions.