施肥对小麦/玉米带田养分吸收及土壤硝态氮累积的影响

小麦与玉米间作是西北干旱灌区常见的高产栽培模式，为了给小麦/玉米带田高效施肥提供科学依据，通过在干旱灌区进行的小麦/玉米带田田间试验，研究了不同施肥模式对小麦/玉米带田产量、养分吸收及土壤硝态氮累积的影响。结果表明，以有机肥与化肥配施、养分均衡供给与合理运筹为核心的优化施肥模式(施有机肥22.5 t/hm2、N 300 kg/hm2、P2O5 120 kg/hm2、K2O 120 kg/hm2，有机肥、全部磷钾肥及20%的氮肥做底肥，80%的氮肥在小麦三叶期追施10%、小麦挑旗期追施20%、玉米喇叭口期追施30%、玉米灌浆中期追施20%)促进了间作体系作物植株对氮、磷、钾等养分的吸收，相对于增量施肥模式，优化施肥模式的氮肥偏生产力和氮肥农学效率分别提高了38.8%和36.9%，氮肥利用效率增加了14百分点，0～120 cm土层土壤硝态氮累积量减少43.9%～58.0%，小麦产量达5 358 kg/hm2，玉米产量达12 453 kg/hm2。

Effects of Fertilization on Nutrients Uptake and Soil Nitrate Nitrogen Accumulation for Wheat and Maize Intercropping

Wheat and maize intercropping is a commonly used high yield cultivation model in the irrigated area of the northwest arid region. To provide reference for efficient fertilization in the intercropped wheat and maize fields, throught field experiment carried out on the intercropped wheat and maize fieldsin the irrigated area of arid region, effects of different fertilization models on yield, nutrients uptake and soil nitrate nitrogen accumulation in intercropped wheat and maize fields were studied. Results showed that optimized fertilization model, using organic fertilizer and chemical fertilizerwith the concept of balanced nutrient supply andrational application as the core(organic fertilizer, N, P2O5 and K2O applied at 22.5 t/ha, 300 kg/ha, 120 kg/ha and 120 kg/ha, respectively with base fertilizer consisting of all the organic fertilizer plus all the phosphorus and potassium fertilizers plus 20% of nitrogenous fertilizer, 10% of the nitrogenous fertilizer dressed at the wheat trefoil stage, 20% of the nitrogenous fertilizer dressed at thewheat flag leaf elongating stage, 30% of the nitrogenous fertilizer dressed atthemaize bell stage, and the last 20% of the nitrogenous fertilizer dressed in the middle of corn filling stage), promoted the the uptakes of nitrogen, phosphorus and potassium nutrients in the intercropping system. When compared with the incremental fertilization model, nitrogen partial factor productivity and nitrogen agronomic efficiency were 38.8% and 36.9% higher, respectively, nitrogen use efficiencywere increased by 14 percentage, nitrate nitrogen accumulation at the soil depth of 0 to 120 cm were decreased by 43.9% to 58.0%, wheat yield was 5 358 kg/ha, and maize yield was 12 453 kg/hain the optimized fertilization model.