31-08-2017, 01:11 PM
Soil moisture sensors measure the volumetric content of water in the soil. Since direct gravimetric measurement of soil free moisture requires the removal, drying and weighting of a sample, soil moisture sensors indirectly measure the volumetric water content using some other soil property, such as electrical resistance, constant dielectric or neutron interaction as an indicator of moisture content. The relationship between measured property and soil moisture should be calibrated and may vary depending on environmental factors such as soil type, temperature or electrical conductivity. Reflected microwave radiation is affected by soil moisture and is used for remote sensing in hydrology and agriculture. Portable probe instruments can be used by farmers or gardeners.
Soil moisture sensors often refer to sensors that estimate the volumetric water content. Another class of sensors measures another property of moisture in soils called water potential; these sensors are commonly referred to as soil water potential sensors and include tensiometers and gypsum blocks.
Soil moisture sensors often refer to sensors that estimate the volumetric water content. Another class of sensors measures another property of moisture in soils called water potential; these sensors are commonly referred to as soil water potential sensors and include tensiometers and gypsum blocks.