Effects of land application of dredged sediment from the Grand Canal(Hangzhou section)on the distribution of phosphorus in soil layers were studied by soil column leaching experiments.The results showed that application of dredged sediment did not significantly increase phosphorus concentration in the soil column leachate.Dry-wet alternative treatment has strong effect on the release of available phosphorus from dredged sediment to subjacent soil layer.After application of dredged sediment,contents of Olsen-P in the upper 15 cm soil layers were markedly higher than that of the control column,but in deeper soil layers, increasing in Olsen-P was insignificant.The increase in Olsen-P was partly due to release of organic acid from dredged sediment,which increased soil organic carbon content and decreased soil pH in the whole soil column.The more dredged sediment was applied,the longer effect on soil and ground water may last.