中文摘要：

选取杭嘉湖地区4种典型稻田土壤开展田间小区试验,研究不同施磷水平的稻田田面水中磷素浓度的动态变化及其影响因素。结果表明,不同水稻土壤类型下磷肥施入后1天均出现田面水总磷（TP）和溶解态反应磷（DRP）浓度的峰值,峰值大小受土壤类型和施磷水平共同影响;峰值出现后,不同土壤类型下田面水TP、DRP浓度均以指数形式下降,并最终保持稳定;磷肥施入后1-3天,田面水中DRP/TP比例可迅速提升至0.6~0.9;施磷水平对田面水中TP、DRP浓度的影响效应随时间逐渐减弱,后期田面水中TP、DRP浓度主要与土壤类型相关。

英文摘要：

The field experiments with four typical paddy soils were conducted to study the temporal changes and the risk of phosphorus loss from paddy field under different P application rates. Results showed the TP and DRP concentrations under all soil types reached their maximum value in the first day after P application, and the maximum values was influenced by both soil type and P rate, thereafter the TP and DRP concentra- tions decreased by an exponential equation, and finally kept at a relatively stable level, 1-3 days after fertili- zation, DRP/TP ratio would rapidly increased to 0.6-0.9. The effect of P application on TP and DRP concentrations in floodwater of paddy fields gradually diminished with increasing. TP and DRP concentrations in floodwater were mainly related to soil type in the late period.