Optimization and Comparison of the Detection Methods for Soil Available Boron Content.

In order to ensure the authenticity and reliability of the 3rd National Soil Survey data, the standard detection methods need to be repeatedly verified to optimize the method suitable for nationwide promotion. At present, the sensitivity of NY/T 1121.8--2006 methylimine-H spectrophotometric to test available boron in soil is low, and factors such as color rendering temperature and light are easy to interfere with the test results. In view of this, this paper analyzed the key factors such as leaching time, leaching method and color rendering conditions in the process of detection of soil available boron by boiling water bath leaching-methylenimine-H spectrophotometric, and explored the optimal conditions for the detection of the method. The results showed that with the conditions of leaching time 12 min leaching time, capping leaching and 23 °C dark environment in color rendering process, it could better reduce the error in the detection of available boron and obtained more accurate results. At the same time, the detection of soil available boron by inductively coupled plasma spectroscopy (ICP-OES) was verified. The detection limits of spectrophotometric and ICP-OES were 0. 012 mg/kg and 0. 009 mg/kg, respectively, which met the requirements of analysis and testing. The accuracy and precision verification results showed that both methods could be used for the detection of soil available boron, and there was no significant difference in the test results of actual samples. Among them, the spectrophotometric method was suitable for the determination of high content (>0. 5 mg/kg) samples, and the ICP-OES method was suitable for the detection of medium and low content samples. Based on the experience of the 3rd National Soil Survey pilot work, it is suggested that ICP-OES should be the first choice for the effective boron determination, which provides reference for The 3rd National Soil Survey. [ABSTRACT FROM AUTHOR]