Method for determining available boron in soil

The invention discloses a method for determining available boron in soil, and relates to the technical field of detection of available boron in soil. The method comprises the following steps: mixing a digestion solution with a to-be-detected soil sample, and carrying out microwave digestion to accelerate the extraction efficiency of available boron in soil and reduce the volatilization of boron element in soil so as to obtain the to-be-detected sample; detecting a to-be-detected sample by using an inductively coupled plasma emission spectrometer to obtain a response value of the to-be-detected sample, and substituting the response value of the to-be-detected sample into the mass concentration-response value standard curve of boron to obtain the mass concentration of effective boron in the to-be-detected sample; the digestion solution is a magnesium sulfate solution, and the concentration of the magnesium sulfate solution is 1g/L; the dosage ratio of the soil sample to be detected to the digestion solution is