Claudinei Martins Guimarães
Abstract:
The Time Domain Reflectometry (TDR) technique has stood out in the evaluation of soil moisture, as an instantaneous, non-destructive, accurate and little dependent method. However, researchers have emphasized the need for specific and continuous calibration for each area of study. Therefore, the objective of this work is to calibrate a portable TDR-type sensor for a Cerrado Distroferric Red Latosol, at three different depths under three different soil management systems. The equipment uses two rods of 0.12 m in length each, records instantaneous reading of the volumetric water content in the soil. The depths of 0 - 0.12, 0.12 - 0.24 and 0.24 - 0.36 m were evaluated from three different systems (no-tillage, crop-livestock integration and conventional tillage). TDR sensor response varied with handling type and depth. After statistical analysis of the data by regression, it was observed a good representation of the humidity values as a function of the sensor response period and the correlation between the humidity by TDR and humidity by the gravimetric method, indicating that the studied device was effective soil moisture measurement at all depths and management systems of the specific latosol analyzed.
