应用“3414”试验建立冬小麦测土配方施肥指标体系

以山东省冬小麦为例，对应用“3414”完全或部分实施试验结果建立磷、钾施肥技术指标体系的技术环节进行探讨，并就当前建立指标体系中遇到的问题进行解析。本研究以相对产量75%、90%和95%为标准将山东省土壤有效磷、速效钾划分为低、中、高和极高4级；并分别用三元二次、一元二次和线性加平台模型对不同土壤养分分级范围内施肥量与产量关系进行模拟，计算最佳肥料用量。结果表明，当山东省土壤有效磷、速效钾含量处于低等级（Olsen-P10 mg/kg；NH4OAc-K50 mg/kg）时，磷、钾肥（P2O5和K2O）用量分别应为100～130和120～150 kg/hm2；中等级（Olsen-P, 10~30 mg/kg; NH4OAc-K, 50～100 mg/kg）时，磷、钾肥用量为80～100和100～120 kg/hm2；高等级（Olsen-P, 30～50 mg/kg; NH4OAc-K, 100～140 mg/kg）时，磷、钾肥用量为60～80和60～80 kg/hm2；当土壤有效磷高于50 mg/kg，速效钾高于140 mg/kg 时，无需磷钾肥施用。

Establishing phosphorus and potassium fertilization recommendation index based on the"3414"field experiments

Recently, numerous field experiments are conducted in national soil testing and fertilization recommendation project, however, how to use these experimental data to establish fertilization recommendation index is urgently needed. Taking the winter wheat “3414” experiments in Shandong Province as an example, the process of establishing fertilization recommendation index was investigated and discussed. Soil Olsen-P and NH4OAc-K were classified as low (75% relative yield), medium (75%–90% relative yield), high (90%–95% relative yield) and very high (95% relative yield) based on the relative yields. Fertilizer recommended rates were simulated by the models of three-factor or one-factor for each “3414” field experiment. The results indicate that phosphorus fertilizer rates (P2O5) are 100–130, 80–100, 60–80, and 0 kg/ha when soil fertility are classified as low, medium, high and very high (Olsen-P10, 10–30, 30–50 and 50 mg/kg), respectively, while potassium fertilizer rates (K2O) are 120–150,100–120, 60–80, and 0 kg/ha (NH4OAc-K 50, 50–100, 100–140 and 140mg/kg). Therefore, establishing fertilization recommendation index based on "3414" field experimental data is practicable.