基于“3414”试验的川中丘陵区油菜施肥指标体系构建

Establishiment of Fertilization Recommendation Indexes of Rapeseed Soil Based on the "3414" Field Experiments in the Middle of Sichuan Hilly Regions

【目的】旨在建立土壤养分丰缺及施肥指标,为当前生产条件下川中丘陵区油菜合理施肥提供参考依据。【方法】本研究汇总了川中丘陵区2005—2009年61个县(市、区)油菜"3414"田间试验数据,采用养分丰缺指标法,以油菜的相对产量为标准将土壤有效磷、速效钾划分为5个等级;确定肥料推荐用量时,氮肥采用"区域总量控制"的方法计算区域内的平均适宜施氮量,磷、钾肥量则由肥料最佳用量与速效养分含量的关系拟合得出。【结果】(1)川中丘陵区油菜地的氮肥平均适宜施氮量为(170±50)kg.hm-2,低肥力土壤氮肥用量上限为250kg.hm-2。(2)当油菜地土壤有效磷(AP)、速效钾(AK)含量处于低等级(AP<5 mg.kg-1;AK<30 mg.kg-1)时,磷(P2O5)、钾肥(K2O)用量分别为100—120 kg.hm-2、90—110 kg.hm-2;较低等级(AP,5—15 mg.kg-1;AK,30—60 mg.kg-1)时,磷、钾肥用量分别为70—100 kg.hm-2、70—90 kg.hm-2;中等级(AP,15—25 mg.kg-1;AK,60—120 mg.kg-1)时,磷、钾肥用量分别为50—70 kg.hm-2、50—70 kg.hm-2;较高等级(AP,25—45 mg.kg-1;AK,120—240 mg.kg-1)时,磷、钾肥用量分别为30—50 kg.hm-2、30—50 kg.hm-2;高等级(AP,>45 mg.kg-1;AK,>240 mg.kg-1)时,磷、钾肥用量分别为<30 kg.hm-2、<30 kg.hm-2。【结论】当前测土配方施肥条件下,川中丘陵区油菜养分管理过程中呈现出减施氮、磷肥(特别是氮肥),增施钾肥的特点。

【Objective】To provide a theoretical basis for balanced fertilization of rapeseed production in the middle of Sichuan hilly regions,abundance and deficiency indexes of soil nutrient and fertilization recommendation indexes were established.【Method】Data were analyzed based on the ＂3414＂ experiments of rapeseed in the field from 2005 to 2009.Making use of plentiful-lack of soil nutrient as an index,soil available phosphorus（AP） and available potassium（AK） were divided into five levels on the basis of different relative yields.Nitrogen fertilizer application rate（N） on average was estimated based on the method of total quantity control,while phosphorus fertilizer（P2O5） and potassium fertilizer application rates（K2O） were calculated by the method of fertilizer response function.【Result】 Regional optimal application rate of chemical fertilizer N on average is（170±50） kg·hm-2.Phosphorus fertilizer application rates（P2O5） are 100-120,70-100,50-70,30-50,30 kg·hm-2（AP5,5-15,15-25,25-45 and 45 mg·kg-1）,while potassium fertilizer application rates（K2O） are 90-110,70-90,50-70,30-50,30 kg·hm-2（AK30,30-60,60-120,120-240 and 240 mg·kg-1）.【Conclusion】Compared with the fertilization recommendation rate calculated by the original system,the fertilization recommendation rate above suggests that nitrogen and phosphorus fertilizer application rates should be decreased,while potassium fertilizer application rates ought to be increased.