巢湖流域氮肥减施下2种控释肥料对水稻产量、氮肥利用率及环境效益的影响

Effects of two controlled-release fertilizers on rice yield,nitrogen use efficiency and environmental benefits under nitrogen fertilizer reduction in Chaohu Lake Basin

探讨2种控释肥料减氮施用对作物产量与氮素利用率及环境效益的影响,为巢湖流域氮肥减量增效、作物丰产及面源污染防控提供理论依据。于2022年在巢湖流域进行2种新型控释肥料减量施用田间试验,采用两因素随机区组设计,选取无机包裹肥和增效控释肥2种控释肥料,并设置5个施氮水平(不施氮、农户模式施氮量及在农户模式施氮量的基础上减量20%、28%和40%,即施氮量为0 kg/hm^(2)、263 kg/hm^(2)、210 kg/hm^(2)、189 kg/hm^(2)和158 kg/hm^(2))。分析2种控释肥料氮肥减量施用对水稻产量及其构成要素、氮素转运利用及水稻季环境效益的影响。与农户模式相比,减氮20%施用2种新型控释肥料对水稻产量无显著影响,可以实现减氮不减产,且显著降低了水稻季活性氮损失的风险。通过回归分析得出,无机包裹肥和增效控释肥的最佳施氮量为230 kg/hm^(2)和195 kg/hm^(2)。

The effects of nitrogen reduction application of two controlled-release fertilizers on crop yield,nitrogen use efficiency and environmental benefits were discussed,which provided a theoretical basis for nitrogen reduction and efficiency increase,crop yield and non-point source pollution prevention and control in Chaohu Lake Basin.A field trial was conducted in 2022 in Chaohu Lake Basin.Two controlled release fertilizers,inorganic coated fertilizer and synergistic controlled release fertilizer,were selected in a two-factor randomized block design.Five nitrogen application levels were set up,namely,no nitrogen application,nitrogen application rate of farmer mode and reduction of 20%,28%and 40%on the basis of nitrogen application rate of farmer mode,and the nitrogen application rates were 0 kg/hm^(2),263 kg/hm^(2),210 kg/hm^(2),189 kg/hm^(2)and 158 kg/hm^(2).The effects of nitrogen reduction application on rice yield and its components,nitrogen transport and utilization,and environmental benefits in rice season were analyzed.Compared with the farmer model,the application of two new fertilizers with 20%nitrogen reduction had no significant effect on rice yield,and significantly reduced the risk of seasonal active nitrogen loss.Regression analysis showed that the optimal nitrogen application rates of inorganic coated fertilizer and synergistic controlled release fertilizer were 230 kg/hm^(2)and 195 kg/hm^(2).