The absorption and desorption of selenium in three kinds of soil (peat soil

bog soil and aeolian sandy soil) were studied using an isothermal adsorption approach in order to explore the effect of wetland soil properties on Se availability in Ruoergai Plateau. The results showed that SeO~2_3-Se adsorbing capacity of the reduced soil was more than that of the oxic soil

the desorbing capacity of water selenium (W-Se) and exchangeable selenium (E-Se) was higher in oxidation state than that in reduction state

but on the contrary the desorbing capacity of la- tent available selenium (LA-Se) in three kinds of soil. Soil oxidation state was helpful to improve the availability of soil Se. With the raising of pH value

SeO~2_3-Se adsorbing capacity decreased

the desorbing capacity of W-Se increased and that of E-Se decreased

but the desorbing capacity change of LA-Se was not obvious in peat soil. Soil organic matter adsorbed Se in large quantities and weakened the availability of soil Se

SeO~2_3-Se adsorbing capacity of peat soil reduced greatly

the amount of W-Se and E-Se enhanced and that of LA-Se diminished obvi- ously after getting rid of soil organic matters.