不同施肥模式对稻田氮磷流失及产量的影响

通过在巢湖派河小流域进行田间小区试验,研究了T1(常规复合肥)、T2(生物有机肥替代30%氮肥)、T3(控失肥替代30%氮肥)、T4(生物有机肥和控失肥各替代15%氮肥)不同施肥模式下水稻田面水中氮磷浓度变化、径流氮磷流失以及水稻产量。结果表明:处理T1的田面水总氮、总磷平均浓度分别为10.30,0.45 mg/L,与T1相比,T2、T3、T4的田面水总氮平均浓度分别降低了12.2%,6.5%,5.3%,田面水总磷平均浓度分别降低了26.7%,15.6%,13.3%。T1的径流总氮、总磷累积流失量分别达17.68,1.60 kg/hm~2,处理T2、T3、T4的径流总氮累积流失量较T1分别降低了35.0%,30.8%,25.5%,径流总磷累积流失量较T1分别降低了16.3%,21.9%,22.5%。处理T1的籽粒产量为8.95 t/hm~2,处理T2、T4的产量较T1分别增加了7.8%,6.5%,差异显著,处理T3的产量较T1降低了2.2%,差异不显著。与施用常规复合肥(T1)相比,生物有机肥替代30%氮肥(T2)、生物有机肥与控失肥各替代15%氮肥(T4)这2种施肥模式既可显著提高作物产量,又能有效降低稻田氮磷流失风险。研究结果可为巢湖流域稻田面源污染的防治提供理论依据。

Effects of Different Fertilization Modes on Nitrogen and Phosphorus Loss and Yield in Paddy Fields

In the field plot experiment of the Chaohu Paihe small watershed, four treatments, including T1 (conventional compound fertilizer), T2 (bio-organic fertilizer replacing 30% nitrogen fertilizer), T3(loss-of-control fertilizer replacing 30% nitrogen fertilizer), and T4 (bio-organic fertilizer and loss-of-control fertilizer replacing 15% nitrogen fertilizer respectively) were set up to study the effects of dynamic changes of nitrogen and phosphorus concentrations in the surface water, nitrogen and phosphorus loss in the runoff, and rice yield under several different fertilization modes. The results showed that the average concentrations of total nitrogen and total phosphorus in the surface water of treatment T1 were 10.30 and 0.45 mg/L, respectively. Compared with treatment T1, the average concentrations of total nitrogen in the surface water of treatment T2, T3, and T4 decreased by 12.2%, 6.5%, 5.3%, the average concentrations of total phosphorus in the surface water decreased by 26.7%, 15.6% and 13.3%, respectively.The total loss of total nitrogen and total phosphorus in the runoff with treatment T1 reached 17.68 and 1.60 kg/hm². Compared with treatment T1, the total loss of total nitrogen in the runoff of treatment T2, T3, and T4 decreased by 35.0%, 30.8% and 25.5%, the total loss of total phosphorus in the runoff of treatment T2, T3, and T4 decreased by 16.3%, 21.9% and 22.5%, respectively. The yield of grain of treatment T1 was 8.95 t/hm². The yields of treatment T2 and T4 increased by 7.8% and 6.5%, respectively, showing a significant difference with T1. The yield of treatment T3 decreased by 2.2% compared with T1, and the difference was not significant. The experimental results show that compared with treatment T1(conventional compound fertilizer), T2(bio-organic fertilizer replaces 30% nitrogen fertilizer), and T4(bio-organic fertilizer and loss-of-control fertilizer replacing 15% nitrogen fertilizer respectively) can significantly increase crop yield, and at the same time, reduce the risk of nitrogen and phosphorus loss from paddy fields effectively. The research results provide a theoretical basis for the prevention and control of non-point source pollution in rice fields of Chaohu Basin.