辽宁省浑河流域不同施肥方式下农田氮素随地表径流与壤中流流失特征

通过人工模拟降雨-径流小区监测的试验方法,设不施肥对照(CK)、基肥穴施(G1)、基肥穴施+追肥面施(G2)、基肥穴施+追肥穴施(G3)4种处理,研究辽宁省浑河流域不同施肥方式下农田氮素随地表径流与壤中流的流失规律,分析不同施肥方式对氮素流失量的影响。结果表明:(1)不同施肥方式下农田地表径流与壤中流产流过程差异显著,地表径流产流时间先于壤中流,同时径流量高于壤中流,是农田主要径流输出方式。G2减少地表径流,G3增大壤中流。(2)地表径流TN平均浓度中G2显著高于其他施肥方式,达到59.00mg/L,其他施肥方式差异较小;壤中流TN平均浓度以G3最高。(3)4种施肥处理,氮素总流失量为385～814mg,各施肥处理的总流失量呈G2>G3>G1>CK,追肥对氮素流失有显著影响。与G2相比,G3在减少地表氮素流失的同时,不会显著增大壤中流氮素流失。

Characteristics of Nitrogen Loss Through Surface Flow and Interflow in Different Fertilization of Farmland in Liaoning Hunhe Basin

A simulated artificial rainfall-runoff plots monitoring experiment was carried out to study farmland nitrogen loss with surface runoff and interflow affected by different fertilization ways in Hunhe river basin in Liaoning province,and exam the influence of different fertilization ways on nitrogen loss.Four treatment models were established: Control(CK),base fertilizer spot application(G1),base fertilizer spot application+topdressing surface application(G2),base fertilizer spot application+topdressing spot application(G3).Results indicated that:(1)With different fertilization ways,the runoff producing of surface runoff and interflow showed significant difference,surface runoff produced runoff before the soil runoff,and the runoff was higher than interflow,which was the main way of farmland runoff output.G2 reduced surface runoff,G3 increased interflow.(2)Surface runoff TN average concentration in G2 was significantly higher than other fertilization methods,which achieved 59.00 mg/L,there were small differences between other fertilization ways,and the highest average concentration of interflow TN was G3.(3)In the four fertilization ways,nitrogen total loss ranged from 385 mg to 814 mg,the total loss in all fertilization treatments were: G2 >G3 >G1 >CK,and topdressing influenced nitrogen loss significantly.Compared with G2,G3 reduced the loss of surface nitrogen,at the same time,it would not significantly increase interflow nitrogen loss.