Soil moisture is a key factor for plant growth. Various countries have conducted a series of studies on soil moisture content. Countries such as the United States, Australia, and Brazil have invested heavily in soil moisture research and have also acquired certain strengths. However, studies on water infiltration and forest hydrology are more important in foreign countries. There is less research on the interaction between vegetation and soil moisture in a region. Domestically, from the 1950s onwards, we have gradually studied soil moisture in detail and started to form a relatively complete theoretical system. Soil moisture is the direct source of plant moisture. Plants absorb water, organic matter and other nutrients in the soil and grow. At the same time, the amount of soil moisture determines how well the plant grows. Therefore, measuring soil moisture has important practical significance. At present, there are many soil moisture determination methods at home and abroad. Specific methods are listed as follows: titration method, weighing method, capacitance method, resistance method, microwave method, neutron method, Karl Fischer method, gamma ray method, nuclear magnetic resonance method, time domain reflectometry (TDR), gypsum method, infrared remote sensing Method and soil moisture sensor method. Although there are numerous methods, we specifically select one of them to measure when measuring soil moisture. Then, I will introduce specific soil moisture determination methods below. Specific methods for measuring soil moisture: 1. Drying method: The drying method is the most common method for measuring soil moisture, and it is also a standard method. Specifically: Obtain a certain amount of soil from the field, and then put it in an oven at 105°C, waiting for drying. The standard for drying is that the weighing is constant before and after twice. Lost water after drying is the moisture content of the soil. The formula is soil moisture content = W/M*100%, M is the weight of soil before drying, and W is the weight of soil moisture, ie the difference between M and the soil weight after drying M'. 2. Resistance method: The resistance method uses the resistance of gypsum, nylon, glass fiber, etc., and their water content. When these intermediates and electrodes are placed in moist soil, then after a while, the moisture content of these things is balanced. Because of the relationship between resistance and moisture content, we previously calibrated the corresponding relationship between resistance and percentage, and then can use these components to obtain a moisture reading in the 1-15 atmosphere suction range. 3. Neutron scattering method: The neutron method is suitable for the determination of soil moisture in the field. It is based on the principle that hydrogen rapidly reduces the speed of fast neutrons and scatters them. Now there are neutron moisture meters on the market that measure soil moisture. The neutron moisture meter has many advantages, but it has considerable limitations on organic soils, and it is not suitable for measuring soil moisture content of 0-15cm. 4, γ-ray method: Similar to the neutron instrument, the γ-ray transmission method uses radioactive sources 137Cs to emit γ-rays, and the probe receives the energy of γ-rays transmitted through the soil, and is converted with the soil moisture content. 5, TDR (Time Domain Reflectometry) method: TDR method is a soil moisture measurement method developed in the 1980s, Chinese time domain reflectometry. This method is quite common in foreign countries and it has just begun to be introduced in China. When all departments pay great attention to it. TDR is a system similar to a radar system. It has strong independence, and its results are basically independent of soil type, density, and temperature. And it is also important that TDR can measure soil moisture under icing, which is unmatched by other methods. In addition, TDR can simultaneously monitor soil water and salt content, and there is almost no difference between the two measurements. The accuracy of this measurement method is evident. Nowadays, with the development of science and technology, instruments are changing with each passing day. Soil moisture analyzers, gps soil moisture meters and other instruments have appeared in the market one after another. And with the development of the computer, the instrument also has a more powerful function, real-time storage of moisture data, print data and can even locate the longitude dimension of the measurement site. These are the functions that previous instruments did not have. The birth of the instrument also makes the determination of soil moisture more convenient and convenient. We have got the EN388,ISO 9001 certified, Shot delivery time,could do Custom made and OEM. 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