河北平原冬小麦增产增效潜力分析

为给提高冬小麦产量及氮肥增产效应提供依据,采用大量农户调查数据和田间试验数据,依据产量差、效率差等指标,对河北平原冬小麦增产增效潜力进行了分析。结果表明,河北平原区冬小麦农户平均产量为6.16t.hm-2,氮肥农学效率为4.0kg.kg-1,氮肥用量为272.7Nkg.hm-2。相对于光温生产值、高产纪录、高产农户和施肥区产量,农户的增产空间分别为214.8%、55.4%、21.3%和11.2%;如果以氮肥农学效率10和30kg.kg-1为目标值,农户的氮肥增效空间分别为150%和650%。河北平原不同生态类型区之间差异不明显。如果能够实现高产高效(产量为高产农户产量,氮肥农学效率为10kg.kg-1),则河北平原区冬小麦可以增产约298.7×104 t,少施氮肥约7.2×104 t(折纯)。建议降低或维持现有氮肥投入水平,通过综合措施增加冬小麦产量。

Potential to Improve the Yield and Nitrogen Use Efficiency of On farm Winter Wheat in Hebei Plain

Winter Wheat is the most important cereal on the Hebei Plain.In the challenge of greater food demand,and protection of resources and environments,it is critical to improve the yield and nitrogen use efficiency(NUE) of winter wheat on the Hebei Plain.The indexes,such as yield gap(△YG),Agronomic efficiency of applied N(AEN) and the gap of AEN(△AEG),were calculated based on the data from farmer surveys and field experiments,and the potential to improve the yield and AEN of on-farm winter wheat was analyzed.The survey of 746 farms in sixteen counties of the Hebei Plain during the 2008-2009 season found that the yield of winter wheat averaged at 6 157 kg·hm-2 and it was 32% of the potential productivity of light and temperature,64% of the yield record,82% of the average yield of high-yield farms and 90% of the average yield of fertilization.Agronomic efficiency of applied N(AEN) for winter wheat was 4.0 kg·kg-1 while the N application rate was 272.7 kg N·hm-2.This was 40% of desired value of 10 kg·kg-1 and 13% of desired value of 30 kg·kg-1 as 10 to 30 kg·kg-1 was the common value of AEN in cereals.There were no significant differences on the potential to improve yield and AEN of on-farm winter wheat among different ecological regions.It was estimated that the total yield could increase by 298.7×104 t and the amount of nitrogen fertilizer could decrease by 7.2×104 t(N) if the average yield of farms would reach the average yield of high-yield farms and AEN would approach 10 kg·kg-1.In conclusion,there is a great potential to increase yield and NUE simultaneously for winter wheat and the key way to realize it is to increase wheat yield through integrated measures while N application rate is kept stable or decreased.