Development history of soil moisture measurement

Soil moisture, or soil moisture, is the basis for the growth of crops. Soil moisture provides the water needed for crop growth as well as the extraction of organic matter and is therefore very important during the growth of the crop. The determination of soil moisture has been involved since the early days. In the 1960s and 1970s, some people proposed the concept of soil moisture. The determination of soil moisture, from the titration method, weighing method, capacitance method, resistance method, drying method, gradually transitioned to the soil moisture analyzer, in addition to the soil temperature and humidity recorder, which can measure soil moisture, also Soil temperature can be measured.

Development of Soil Moisture Determination: The concept of lyrical condition was first proposed in the 1970s. At the same time, the public opinion of wheat and other plants was monitored. Further research on lyrical conditions and its rapid development were in the late 1980s. Jackson et al. proposed the concept of Crop Water Stress Index (CWSI) by studying the temperature of the crown, that is, the canopy temperature measured by an infrared thermometer, which can be estimated based on the dry and humid air temperature and net radiation in the energy balance formula. To calculate CWSI. According to the heat balance equation, the concept of crop water deficit index was put forward, and it was proved that there was a good correlation between water deficit index and soil moisture content. Others have established prediction models for soil moisture at different depths. By analyzing the temperature of the canopy, the water stress index and the condition of the lyrical condition are obtained. In the process of the detection, the operation is troublesome and also affects the measurement result.

It can be seen that the determination of soil moisture has been slowly progressing after decades of exploration. The multi-point soil temperature and humidity recorder is a combination of high-tech products, because it uses the design principle of the sensor, through the sensor to determine the moisture and temperature, to better understand the soil properties.