The determination of soil moisture content has two purposes: First, to understand the actual water content of field soil, so that timely irrigation, waterlogging or drainage, in order to ensure the normal growth of the crop; Second, as the basis for the calculation of the results of the analysis. There are many ways to determine the actual soil moisture content in the field, and the instruments used are also different. Here we focus on the determination of the moisture content of dried soil samples. Related soil moisture analyzer please see: http:// Slingshot Traditional Rubber Band Changzhou Golden Oak Rubber Plastic Polymer Co.,Ltd , https://www.jnspullrope.com
Equipment and Materials Earth Drill, Soil Screen (1mm aperture), Aluminium Box, Analytical Balance, Electric Constant Temperature Oven, Desiccator (with color change silicone)
Method and procedure
1. Selection and preparation of soil samples
(1) Air-dried soil samples: Select a representative sample of air-dried soil, crushed, passed through a 1mm sieve, and mixed until ready for use.
(2) Fresh soil samples: Take a representative sample of fresh soil in the field, scrape off the upper floating soil in the soil drill, and apply about 20 g of soil to the desired depth in the middle of the soil drill. Accurate quality of the aluminum box, tightly closed, into a wooden box or other containers, brought back to the interior, wipe the aluminum box clean, immediately weighed to determine moisture.
2. Determination of moisture content of dried soil samples
Take the aluminum box in a thermostatic oven at 105°C for about 2 hours. Transfer to a desiccator and cool to room temperature. Weigh it to the nearest 0.001g. Mix the dried soil sample with a corner scoop and dip about 5 g. Evenly spread the aluminum box. Cover, cover, weigh, accurate to 0.001g. The aluminum box cover was peeled off, placed under the box, and baked in an oven preheated to 105±2°C for 6-8 hours. Remove, cover, move into the desiccator, cool to room temperature, and immediately weigh. The determination of moisture in air-dried soil samples should be performed in two parallel assays.
3. Determination of fresh soil moisture
An aluminum box containing fresh soil samples was weighed on an analytical balance, and the lid was peeled off, placed under the box, placed in an oven preheated to 105±2°C, and baked for 12 hours. Remove, cover, cool to room temperature in a desiccator and immediately weigh. Determination of fresh soil moisture should be done in 3 replicates.
4. Result calculation