氮肥形态和地膜覆盖对坡耕地玉米产量和土壤氮素流失的影响

Effects of Different Nitrogenous Fertilizer Modality and Film Mulching on Corn Yield and Soil Nitrogen Loss of Slope Land

采用二因素四水平随机区组试验设计,利用模拟径流小区观测的方法,研究氮肥形态和覆盖对坡耕地玉米产量及土壤氮素流失通量及途径的影响。结果表明:土壤径流以地表径流为主,氮素主要流失途径是地下径流,占总径流量的71.3%,氮素流失的主要形态是硝态氮,占无机氮的92.0%,占水溶性总氮的57.1%。地膜覆盖降低径流深和土壤侵蚀量,增加水溶性氮流失量,提高玉米产量,但是酰胺态氮肥和缓控释肥地膜覆盖可降低氮素流失量,且酰胺态氮肥对玉米增产效果显著;裸地条件下硝态氮肥和缓控释肥可降低地下径流深和氮素流失量,且缓控释肥对玉米增产效果显著。综合考虑水土流失治理和粮食增产增收,四川紫色坡耕地适宜肥料类型为缓控释肥,其次是硝态氮肥,酰胺态氮肥通过地膜覆盖也能较好地控制氮素流失和增加玉米产量。

By using two factors and four levels randomized block experiment design,utilizing simulated runoff observation method,the effects of nitrogen forms and film mulching on corn yield and soil nitrogen loss fluxes and approach in slope land were studied.The results showed that the main runoff approach of soil was surface runoff,the main runoff approach of nitrogen was underground runoff,accounting for 71.3% of runoff,the main runoff form of nitrogen was the nitrate nitrogen,accounting for 92.0% of IN,and accounting for 57.1% of TDN.the depth of runoff and soil erosion were reduced by plastic film mulching,the loss of TDN and corn yield were increased by plastic film mulching,but nitrogen loss was reduced by amide nitrogen fertilizer and slow controlled release fertilizer on plastic film mulching,moreover corn yield was increased significantly by amide nitrogen fertilizer;the depth of underground runoff and nitrogen loss were reduced by nitrate nitrogen fertilizer and slow controlled release fertilizer on bare conditions,moreover corn yield was increased significantly by slow controlled release fertilizer.Considering the soil erosion control and grain increase production,the suitable fertilizer type in Sichuan purple slope land were slow controlled release fertilizer,the next was nitrate nitrogen fertilizer,the amide nitrogen fertilizer could not only control nitrogen loss,but also increase corn yield by plastic film mulching.