Taking the total desorption quantity of Ca2+
and pH of the equilibrium desorption solution as the representative indexes to evaluate the desorption of soluble matters,this paper primarily investigates the effect of Na+
on the desorption of soluble matters,based on the static state experiments. The results indicate that,with respect to the same sediment and particle size,the total desorption quantity of soluble matters increases with the increment of initial Na+
concentration of the desorption solution,and gradually reaches a maximum amount. With the same sediment but different particle size or in the same particle size but different sediment,the total desorption quantity of soluble matters is of great difference from the same initial Na+
con-centration. For the same initial Na+
concentration with different soluble matters,the variation of the total desorption quantity with sediment components or particle size is also different. With the same sediment,particle size and initial Na+
concentration,the desorption process has a good concomitance with different soluble matters.