渭北旱塬小麦施肥效果及肥料利用效率研究

总结2006~2009年陕西省渭北旱塬测土配方施肥项目180个3414试验数据，分析当前生产条件下旱作区小麦施肥效果以及施肥量、 土壤肥力水平对小麦产量、 经济效益、 肥料利用效率等的影响，为提高旱作小麦产量和肥料高效利用提供依据。结果表明， 施用氮（N）、 磷（P2O5）、 钾肥（K2O）小麦分别增产986、 679和405 kg/hm2，增产率为30.0%、 18.9%和9.5%，增收1098、 810和392 Yuan/hm2，对小麦产量的贡献率分别为21.5%、 14.8%和8.8%，农学效率分别为6.4、 7.1和7.1 kg/kg; 施肥增产、 增收效果以及肥料贡献率均表现为N＞P2O5＞K2O，农学效率表现为P2O5＝K2O＞N; 与不施肥相比，平衡施用氮、 磷、 钾肥（N+P2O5+K2O）小麦增产73.0%，增收1923 Yuan/hm2，对产量的贡献率为40.0%，农学效率为5.8 kg/kg; 过量施用氮、 磷、 钾肥均无显著减产效应，推荐施肥处理化肥的增产、 增收效果， 对产量的贡献率以及农学效率均最高。土壤肥力对化肥肥效有显著影响，投肥于中、 低肥力土壤既能实现养分高效利用又能获得较大经济效益。与20世纪80年代相比，氮肥利用效率明显降低，磷肥肥效基本不变，而钾肥肥效在快速提升。合理施肥与耕作、 栽培等多种措施相结合是旱区作物增产、 增收的有效途径。

Effects of N, P and K fertilization on wheat yield and fertilizer use efficiency in Weibei rainfed highland

The purpose of this research was to study the fertilization effect on wheat, and to investigate the effect of fertilizer application rate and fertility level on the yield, profit, fertilizer contribution rate (FCR) and agronomy efficiency (AE) under present conditions based on the 180 3414 field experiments in Weibei rainfed highland during 2006 to 2009. The results indicate that the yields of wheat are improved about 986, 679 and 405 kg/ha and the yield increase rates are 30.0%, 18.9% and 9.5% respectively by applying nitrogen (N), phosphorus (P2O5) and potassium (K2O) fertilizers. The average profits are increased about 1098, 810 and 392 Yuan/ha, which correspond to 21.5%, 14.8% and 8.8% of FCR, and 6.4, 7.1 and 7.1 kg/kg of AE respectively. The increased yields, profits and contribution rates of fertilizers are N＞P2O5＞K2O, and the AEs are P2O5＝K2O＞N. The N2P2K2 is the best treatment according to the yield, profit, FCR and AE. Compared with the CK, the yield and profit under the balanced fertilization are increased by 73.0% and 1923 Yuan/ha respectively, and the FCR is 40.0% and AE is 5.8 kg/kg. The yield is not significantly decreased under the excessive fertilization. In medium and low fertility soils, the fertilization has high fertilizer use efficiency and high profit. The use efficiency of N decreases significantly, the use efficiency of P2O5 remains the same basically and the use efficiency of K2O increases rapidly compared with those in 1980s. The most effective way of increasing the yield and profit of wheat in rainfed areas is to combine rational fertilization, farming and cultivation.