小麦／玉米带田不同用量氮肥残效及回收率

Residual Effects and Recovery Rate of N Fertilizer in Wheat/Maize Strip Intercropping

３年小麦／玉米带田定位试验研究明确了①每公顷总量分别为４５０、９００和１３５０ｋｇＮ的氮肥第１年一次性施用和分年施用的增产效果，每公顷４５０ｋｇ左右Ｎ为带田适宜施氮量；②一次性施用氮肥后的残效、影响残效大小及持续性的主要因素是氮肥用量及土壤保肥性；③不同用量及不同分配方式氮肥的当年利用率比累积利用率低５．７％～２．０％，评价氮肥利用率的高低时，应将残效考虑在内；④等量氮肥分年施用与一次性施用相比。

year wheat/maize strip intercropping field experiments showed ① Rational rate of N fertilizer application in the first year with single application or application in years was 450 kg N/hm 2 for wheat/maize strip intercropping;② The key factors of residual effects and sustain after one time application of N fertilizer depend mainly on the application amount of N and soil nutrient holding capacity; ③ The first year utilization ratio of N fertilizer with different application amount and differently distributive application ways is 5.7￣20.0% lower than that of accumulative utilization,and the residual effects should be taken into consideration when the utilization ratio is evaluated; ④ Application of certain amount of N fertilizer in years had much better results than single application only in the first year.