节肥控污施肥模式对双季稻田氮磷径流损失的影响

Effects of Optimal Fertilization Practice on Nitrogen and Phosphorus Runoff Loss in Double-cropping Paddy Rice Field

利用田间小区试验进行原位监测,研究了节肥控污施肥与习惯施肥两种不同施肥模式对双季稻田地表径流中氮磷的形态特征及流失量的影响。结果表明:稻田地表径流主要受降雨驱动,当降雨量大于24.4 mm时产生地表径流;氮磷径流流失量主要与径流中氮磷浓度相关; NH_4^+-N和悬浮颗粒结合态磷分别是氮、磷流失中比重最大的形态;节肥控污施肥模式全稻季的TN、TP、NH_4^+-N、NO_3^--N的流失量及氮磷流失系数均较常规施肥模式减少。

Through field plot experiment, the effects of different fertilization patterns （optimal fertilization practice, and usual fertilization practice） on the modality and loss amount of nitrogen and phosphorous in surface runoff of double-cropping paddy rice field were investigated. The results showed that rainfall mainly led to the surface runoff, and the surface runoff stably occurred when rainfall amount was bigger than 24.4 mm. The loss amount of nitrogen and phosphorus in runoff mainly depended on the concentration of nitrogen and phosphorus in runoff. NH4^＋-N and suspended-particle-binding-state phosphorus were the major modality of nitrogen and phosphorus runoff loss, respectively. The optimal fertilization practice caused less loss amount of TN, TP, NH4^＋-N and NO3^--N, as well as lower loss coefficients of nitrogen and phosphorus in the whole rice growth season than the usual fertilization practice.