The time of issue:2012-06-19 9:00:03 view number:
Soil moisture determination method are many: titration, gravimetric method, capacitance, resistance method, microwave method, neutron method, Karl Fischer method, the ¦Ã-ray method, nuclear magnetic resonance method, time domain reflectometry (TDR), gypsum , infrared remote sensing and soil moisture meter method. Different methods, the simple and the accuracy of the determination of soil moisture content are different. Soil moisture is the most important source of plant water, its content is directly related to whether we need irrigation, crop growth rate and results. The absorption of plant organic matter, also requires the participation of the plant body of water, soil moisture measurement is very important. Many countries on soil moisture in-depth understanding, such as the United States, Australia and other developed countries, more research efforts at the cost of increased soil moisture. Since the 1950s, the domestic gradually on soil moisture and detailed and in-depth study of the formation of a more complete theoretical system.
There are two ways to deepen the measurement of soil moisture.
Drying method: drying method is relatively simple approach is the most common method of measuring soil moisture, but also one of the Standards Act. Their specific operation is as follows, from the field to obtain a certain amount of soil, weighing balance, and then into the oven of 105 ¡ã C (evaporation of water temperature to 100 ¡ã C), waiting for the drying. Which to judge the standard of laboratory drying, the average is around the two measurements, the weight of not more than one value shall prevail. Weighed again after drying. Around twice the weight difference is the soil moisture content. Which formula for soil moisture = W / M * 100%, and M is the weight of the soil before drying, W is the weight of the soil moisture, M and after drying the soil weight M 'difference.
Soil moisture meter method: the determination of soil moisture than soil moisture meter to another, such as soil moisture and temperature Tachometer, soil moisture detector and so on soil moisture measurements. Soil Moisture and Temperature Tachometer is a versatile instrument, or determination in the determination of soil moisture, soil temperature, soil moisture tester, and more suitable for long-term record on the same monitoring points to compare. Soil moisture tester through the instrument to launch a certain frequency of electromagnetic waves, electromagnetic waves along the probe transmission to reach the bottom of the return, to detect the probe output voltage depends on the soil water content due to changes in soil dielectric constant, the relationship between output voltage and water can calculate the water content of the soil. Zhejiang Top production, soil moisture analyzer has a powerful data storage space, at the same time to record 2000 sets of data, and can be connected with computer, import the data into the computer, also can carry the GPS function, in the determination of soil moisture at the same time, real-time display of measured point latitude and longitude, in order to do spatial differentiation.
Although the drying method and soil moisture meter method for the two distinct methods of measurement, the result is only one which is to measure soil moisture content set.