SEQUENTIAL EXTRACTION A NEW PROCEDURE FOR SELENIUM OF DIFFERENT FORMS IN SOIL

A modified sequential extraction procedure for Selenium of different forms in soil was developed. By the procedure, Selenium in soil was divided into five fractions: (1) Water soluble, (2) exchangeable, (3) acid soluble, (4) organic compound and (5) residual. All the five forms of Selenium and total Selenium were determined with HG-AFS, showing that the method is precise, accurate, reliable and easy to operate..