SOIL MOISTURE GRADIENT HYDROMETER
There is proposed the design of a gradient soil moisture meter which includes humidity sensors placed along the horizons of the soil profile, it registers humidity in some soil layers, and it is tested under field conditions. The moisture meter consists of a case, contact block, lead cables, battery, digital voltmeter and capacitive humidity sensors. The contact block is located in the neck of the case, cables are inside the case and capacitive sensors are placed horizontally along the layers of the soil profile. The battery and digital voltmeter are connected to the contact block and placed on the soil surface. The device is installed vertically in the corner of the soil section. The device is installed vertically in the corner of the soil section. Humidity sensors are embedded in the side walls of the section. The device case and all cable connections to the case are sealed. During the field test there was arranged a flood site around the device, the soil was saturated up to the full moisture capacity and the indicators were calibrated: soil moisture - the voltage of the analog outputs. In parallel, the soil moisture was measured by the thermostatic-weight method. The humidity measurement error did not change for two weeks. The efficiency of the proposed design of the moisture meter is confirmed. The stability of the moisture meter was established within 3 weeks with a relative measurement error of 2 ... 3%. The moisture meter is installed in the soil for the whole growing season.