A PRELIMINARY STUDY ON LEACHING OF SELENIUM IN THE SOILS OF CHINA
我国土壤中硒的淋溶

It has been shown by study on eight typical soils of China that leaching of Se is positively related to pH, negatively related to content of clay particals, A12O3, R2O3and Se-absorption coefficient in soils. These factors result in the differences of Se leaching in various soils. The percentage of Se leaching in different soils was estimated according to the precipitation condition in local area respectively. It is shown that percentage of Se leaching is affected by physical and chemical parameter of soil such as organic matter etc.,and ranged from 0.35% to 2.22%, in the order as: purplish soil>drab soil>dark brown earth>chernozem>black soil>red earth = laterit soil>sierozem. Comparing the leaching of Se in Se deficient soil-Keshan disease area with Se sufficient soil-disease free area, Se leaching in soil is signifcantly higher in low Se area than that in non-disease area. Therefore, this may be one of the causation for low level of Se in soils of Keshan disease belt