A field plot experiment was conducted to study the effects of alternate wetting and drying( AWD) irrigation and controlled-release fertilizers( controlled-release bulk blending fertilizer and polymer-coated urea: BBF and PCU) application on the nitrogen( N) dynamics in percolation water at 30 cm soil depth in paddy fields in Taihu Lake region. Results showed that TN,NH+4-N and NO-2-N concentrations of the percolation water in all treatments peaked within the first 10 days after fertilization,and decreased g...