通过在定西市唐家堡试验站进行的为期2年的旱作冬小麦单作田间试验,研究优化施肥、秸秆还田、免耕、膜上覆土、全膜垄沟种植和砂田等措施对作物产量与水分利用效率,以及收获后土壤硝态氮残留,夏闲期残留硝态氮淋溶的影响.结果表明：底肥和追肥分段施用的优化施肥模式较不施肥和农户传统施肥模式可以显著提高小麦产量和施肥效果(P >0.05),不施肥模式下产量仅能达到其他施肥处理水平的46%~92%,且收获指数最低；优化施肥结合全膜垄沟和砂田栽培模式增产效果最明显,分别比农户传统施肥模式增产43.4%和41.4%,水分利用效率提高56.9%和46.1%.全膜垄沟和砂田的栽培模式可提高小麦拔节期土壤水分,促进小麦对土壤氮素吸收,在小麦休闲期,全膜垄沟和砂田模式0~100 cm 土层累积的硝态氮分别增加了83.2和86.2 kg/hm2,能够提供下季小麦吸收利用,避免土壤残留硝态氮向下层淋溶,从而实现高产稳产.全膜垄沟种植模式和砂田模式可以更好地提高冬小麦的产量、水分利用效率,降低了氮素在土壤中的残留,并且避免了土壤中的硝态氮的向深层淋溶.%The monoculture field experiments of winter wheat were conducted at Tangjiabao Experi-ment Station of Dingxi for two years,and effects of some techniqiues were studied on yield and water use efficiency.The results showed that the optimum fertilization model segmented fertilization of basal and top dressing fertilizer was superior to the no fertilization model and the farmer traditional fertilization model, which improved the yield-increasing effect by fertilizer (P > 0.05 ).The yield of no fertilization model reached 46%~92% levels of other models,and with the lowest harvest index.Compared with traditional fertilization model of farmers,the cultivation patterns of whole film with furrow and sandy field increased yield by 43.4% and 41.4%,respectively,and increased water use efficiency (WUE )by 56.9% and 46.1%, respectively,which also increased the soil moisture at the jointing stage of wheat,promoted N uptake,and increased nitrate nitrogen of 0~100 cm soil layer by 83.2 and 86.2 kg/hm2 in fallow period.The nitrate ni-trogen could be used for next season of wheat preventing nitrate-N leaching to deep soil.It is suggested that the cultivation patterns of whole film with furrow and sandy field are high and stable yield.The whole film furrow planting pattern and sandy field model can significantly improve the wheat yield,water use effi-ciency,reduce the residual nitrogen in soil,and avoid the nitrate nitrogen in the soil to deep leaching.
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