中文摘要：

以提高玉米氮素利用效率、减少氮肥污染为目标,在甘肃省定西市李家堡设置了露地（NM）、半膜平作（HM）、全膜平作（CM）和全膜双垄（CMRF）沟播等田间试验处理,对其土壤剖面中NO3--N的积累强度、玉米干物质积累及氮素利用效率进行了系统研究。结果表明：整个生育期覆膜处理在0～10 cm表层中NO3--N浓度最高,明显高于NM,具有表聚现象。所有处理NO3--N含量在140 cm土层以下均有积累。全生育期植株平均氮素积累量表现为：CMRF〉CM〉HM〉NM。籽粒氮积累量CMRF较CM和NM高出20.48%和87.87%,说明CMRF显著增强了植株对土壤氮的利用和氮素向籽粒的转运。生物产量CMRF较HM增产37.60%,经济产量增产49.84%,氮素收获指数CMRF较HM显著提高22.55%。不同处理之间的NUE差异显著（P〈0.05）,CMRF较HM显著提高53.98%。

英文摘要：

A field experiment in Lijiabu,Dingxi City of Gansu province,was carried out based on improving nitrogen use efficiency and reducing the pollution of nitrogen fertilizer.Four treatments,namely flat-planting with no mulching（NM）,half-mulching and flat-planting（HM）,complete-mulching and flat-planting（CM）,completely mulched alternating narrow and wide ridges with furrow planting（CMRF）,were designed to study accumulation of residual NO3--N and dynamic accumulation and distribution of dry matter and nitrogen use efficiency.The results showed that in the whole growth period of mulching treatments NO3--N content of 0～10 cm soil layer was highest and were significantly higher than that of NM,indicating there existed NO3--N surface accumulation in mulching treatments.NO3--N content of all treatments under 140 cm soil layer was accumulated.The average nitrogen accumulation in the whole growth period was：CMRF〉CM〉HM〉NM.Compared with CM and NM,grain nitrogen accumulation of CMRF was increased by 20.48% and 87.87%,showing that CMRF significantly enhanced plants nitrogen utilization from soil,as well as transport of nitrogen to grain Biomass yield of CMRF was 37.60% higher than that of HM,maize yield was increased by 49.84%,and nitrogen harvest index was significantly increased by 22.55% compared with HM.During different treatments nitrogen use efficiency of maize was significantly different at 0.05 level,CMRF was significantly increased by 53.98% than NM.