【摘 要】
：
在宁南山区的固原市原州区和彭阳县调查65个春玉米种植户的产量、施肥量及肥料种类等.结果 表明,该区域春玉米平均产量为9.4 t/hm2,80％的调查农户春玉米产量处在适中及偏低以下水平(＜10.5 t/hm2).春玉米生产中N、P2O5、K2O养分的平均用量分别为353、253、370 kg/hm2,其中,化肥N、P2O5投入分别为314、175 kg/hm2,K2O全部来自有机肥.有机肥以牛粪为主(施用比例达89.2％),平均用量为25.6 t/hm2.氮、磷养分的平均偏生产力分别是31.6、61.1
【机 构】
：
宁夏农林科学院农业资源与环境研究所,银川750002;北方民族大学生物科学与工程学院,银川750021
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在宁南山区的固原市原州区和彭阳县调查65个春玉米种植户的产量、施肥量及肥料种类等.结果 表明,该区域春玉米平均产量为9.4 t/hm2,80％的调查农户春玉米产量处在适中及偏低以下水平(＜10.5 t/hm2).春玉米生产中N、P2O5、K2O养分的平均用量分别为353、253、370 kg/hm2,其中,化肥N、P2O5投入分别为314、175 kg/hm2,K2O全部来自有机肥.有机肥以牛粪为主(施用比例达89.2％),平均用量为25.6 t/hm2.氮、磷养分的平均偏生产力分别是31.6、61.1 kg/kg;46.2％农户的化肥N施用量为300～400 kg/hm2,52.3％农户的化肥P2O5用量为100～ 200 kg/hm2;72.3％、83.0％的农户分别施用过量的化肥N、P2O5;化肥种类以二铵、尿素为主(施用比例分别达86.2％、83.1％).该区域氮磷化肥减施潜力分别为26.8％和37.1％,宁南山区春玉米在有机肥大量施用的条件下,化肥氮磷减施是节本增效的关键措施.
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