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FIG. 7. (a) Water content measurements in a silt loam soil during two irrigation events for the seven sensors shown in Fig. 6. Diurnal fluctuations in sensor response occur as a result of temperature changing the bulk soil electrical conductivity to which certain instruments are sensitive. (b) The calibration indicating the Acclima is the only sensor to achieve accurate water content determination in this trial. Deviations from absolute values are considered to occur because of small sensor sampling volume.
