It has advantages of convenience and rapidity when using soil equivalent dielectric solution instead of soil to test and evaluate performance of soil moisture sensor. To verify whether the measurement result measured in dielectric solution is consistent with that measured in actual soil

a series of dielectric solution whose equivalent soil volumetric water content is 0. 9 %

51. 8 % is prepared by mixing deionized water with 2-isoproxyethanol or dioxane; two kinds of soil samples whose soil volumetric water content corresponds to equivalent soil volumetric water content of dielectric solution are prepared by using typical red soil in Guangzhou region and

typical laterite in Leizhou peninsula as material respectively; and performance of soil moisture sensor is tested in three kinds of medium which are dielectric solution

red soil samples and laterite samples respectively from four aspects such as electrical characteristic

function relationship with soil water content

temperature variability and stability

and then the results measured in dielectric solution are compared with that measured in the other two kinds of medium. Experimental results show that test results in dielectric solution are basically consistent with the test results in red soil samples and laterite samples

and dielectric solution can replace soil samples to test soil moisture sensor performance to some extent.