【摘 要】
：
依据文献资料以及农户调研数据,对北方玉米种植区的施肥现状和节肥潜力进行分析.调研数据表明,在当前北方玉米区平均玉米产量为9894 kg/hm2水平下,养分投入总量平均为512 kg/hm2,纯氮(N)投入总量为307 kg/hm2,纯磷(P2O5)投入总量为137 kg/hm2,纯钾(K2O)投入总量为68 kg/hm2.氮、磷、钾肥的偏生产力分别为33、78、135 kg/kg.当前农户施肥量总体超量,以最优化肥偏生产力为依据,推荐当前土壤条件下的北方玉米的平均氮、磷、钾施用量分别为193、86和60
【机 构】
：
中国农业大学资源与环境学院,北京100193
论文部分内容阅读
依据文献资料以及农户调研数据,对北方玉米种植区的施肥现状和节肥潜力进行分析.调研数据表明,在当前北方玉米区平均玉米产量为9894 kg/hm2水平下,养分投入总量平均为512 kg/hm2,纯氮(N)投入总量为307 kg/hm2,纯磷(P2O5)投入总量为137 kg/hm2,纯钾(K2O)投入总量为68 kg/hm2.氮、磷、钾肥的偏生产力分别为33、78、135 kg/kg.当前农户施肥量总体超量,以最优化肥偏生产力为依据,推荐当前土壤条件下的北方玉米的平均氮、磷、钾施用量分别为193、86和60 kg/hm2.各区域均需要不同程度地减少氮磷肥投入,其中,陕西省的氮素节肥潜力最大(53％),黑龙江省的磷肥节肥潜力最大(50％).吉林、内蒙古、新疆钾肥节肥潜力是26％～ 41％,黑龙江省、陕西省和甘肃省的钾肥施用量不足,需增施钾肥.
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