基于土壤肥力与目标产量的冬小麦变量施氮及其效果

Results of variable-rate nitrogen fertilization of winter wheat based on soil fertility and yield map

基于田间18m×18m土壤碱解氮测定数据和2001年的小麦产量图数据,采用目标产量模型,设计了变量施氮处方,进行变量施氮试验。以相邻地块均一施肥区为对照,结果表明,变量施氮区产量略低于均匀施肥,且产量变异系数增加;产量构成因子中,变量区的穗密度与对照区基本持平,但变量区的穗密度变异系数较低;变量区的穗粒数低于对照区,变异系数增加;变量区的千粒重高于对照区,变异系数增加;变量区的蛋白质含量略高于对照区,但变异系数也较高;变量区的肥料经济效益略低于对照区,但变量施氮降低了土壤硝态氮浓度,减小了污染地下水的可能性,生态效果明显。

Based on 18 m×18 m grid-sampling of Alkali-soluble soil nitrogen and yield map in 2001, variable-rate nitrogen fertilization prescription was produced for winter wheat and examined in farmland in 2002. Compared to uniform nitrogen fertilization, variable-rate nitrogen fertilization caused slightly lower yield and higher coefficient of variance of yield. Ear density in variable-rate zone is approximately equal to that in the uniform fertilization zone, but has lower coefficient of variance. Number of grains per ear in variable rate zone is less than that in the uniform fertilization zone, and has a higher coefficient of variance. Both grain weight in variable rate zone and its coefficient of variance are higher than those in the uniform fertilization zone. Grain protein content in variable rate zone is slightly higher than that in the uniform fertilization zone, while its variability is also higher. Economical benefits of fertilization in variable rate zone are smaller than those in uniform zone. Soil nitrate concentration in variable rate zone after the wheat season is much lower than that in the uniform fertilization zone, and the risk of groundwater pollution by soil nitrate is reduced.