中文摘要：

通过蒸渗测坑对水稻拔节孕穗期和抽穗开花期2个重要生育期进行水位调控试验,研究单个生育阶段旱涝交替胁迫及2个生育阶段连续旱涝交替胁迫的稻田地表水、地下水总磷（TP）质量浓度变化。结果表明：旱涝交替胁迫对稻田地表水、地下水TP质量浓度变化影响显著,先旱后涝处理地表水的平均TP质量浓度比先涝后旱处理地表水TP质量浓度高,且P释放量下降速率快;地下水各处理受涝阶段的平均TP质量浓度比受旱阶段高,旱涝急转后TP质量浓度显著增加;与单个生育期进行旱涝交替胁迫处理相比,连续2个生育期进行旱涝交替胁迫处理时抽穗开花期TP质量浓度变化规律相似,但地表水平均TP质量浓度偏低,地下水平均TP质量浓度偏高。

英文摘要：

Through water level control tests in two important growth stages of rice, the jointing-booting and heading- flowering stages,the change of total phosphorus （TP） mass concentration in surface and subsurface water of a paddy field were studied using lysimeters under alternative stresses of drought and waterlogging （ASDW） in individual stages and two consecutive growth stages. The results show that ASDW had a significant influence on the change of TP mass concentrations in surface and subsurface water of a paddy field, the TP mass concentration in surface water with the treatment of waterlogging after drought was much higher than it was with the treatment of drought after waterlogging, and the declining rate of phosphorus release amount was faster. The mean TP mass concentration in the waterlogging phase was higher than in the drought phase with all treatments of subsurface water. The TP mass concentration increased significantly after the abrupt alternation from drought to waterlogging. Compared with that during the individual growth stages with the treatment of ASDW,the change of TP mass concentration in the heading- flowering stage during the two consecutive growth stages with the treatment of ASDW was similar, the mean TP mass concentration in surface water was lower, and the mean TP mass concentration in subsurface water was higher.