暴雨条件下不同灌排模式稻田排水中氮磷变化规律

为研究暴雨条件下不同灌排模式稻田排水中氮磷质量浓度变化规律，减少农田面源污染，提高氮肥的利用效率，在江苏省宿迁市宿城区运南灌区开展田间试验。试验结果表明：与常规灌排模式( CK)相比，控制灌排模式节水18.7%，排水总量减少50.6%，水稻产量减少3.6%；控制灌排模式由于增加了稻田蓄水深度，减少了雨后排水量，延迟了雨后排水时间，稻田排水中NH+4-N、NO3--N、TN和TP流失总量分别比CK减少48.15%、49.09%、45.54%和49.10%，节水减排效果显著。

Changes of nitrogen and phosphorus concentrations in surface drainage from paddy field under different irrigation and drainage modes

A field experiment was conducted in the Sucheng District, in Suqian of Jiangsu Province, in order to study the changes of the concentrations of nitrogen and phosphorus in surface drainage from a paddy field after a rainstorm with different irrigation and drainage modes, and to reduce agricultural non-point source pollution and improve the utilization efficiency of nitrogen fertilizer. The experimental results show that, compared with conventional irrigation and drainage modes, the controlled irrigation and drainage mode caused an 18. 7% reduction in total irrigation water, a 50. 6% reduction in total drainage water, and a 3. 6% reduction in rice yield. As the controlled irrigation and drainage mode increased the storage water depth in the paddy field, it caused drainage to decrease after the rainstorm, the drainage time to be delayed, and the total amounts of NH⁺₄-N, NO^-₃-N, TN, and TP losses in the surface drainage from the paddy field to decrease by 48. 15%, 49. 09%, 45. 54%, and 49. 10%, respectively, indicating a significant effect in water conservation and drainage reduction.