宁南山区春玉米施肥现状及减施潜力

Current Status of Fertilizer Application and the Potential for Fertilizer Reduction in Spring Maize in the Southern Mountain Region of Ningxia

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/hm^(2),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/hm^(2))。春玉米生产中N、P_(2)O_(5)、K_(2)O养分的平均用量分别为353、253、370 kg/hm^(2),其中,化肥N、P_(2)O_(5)投入分别为314、175 kg/hm^(2),K_(2)O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/hm^(2)。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/hm^(2),52.3%农户的化肥P_(2)O_(5)用量为100~200 kg/hm^(2);72.3%、83.0%的农户分别施用过量的化肥N、P_(2)O_(5);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。

The yields,fertilizers input rates and fertilizer types of 65 maize growers were investigated in Yuanzhou district and Pengyang county of Guyuan city.The results showed that spring maize yield was 9.4 t/ha on average.About 80%of the households had medium or low maize yield(lower than<10.5 t/ha).The average N,P_(2)O_(5),and K_(2)O application rates in spring maize were 353,253,and 370 kg/ha,respectively.Among them,N and P_(2)O_(5) input from chemical fertilizers were 314 and 175 kg/ha,respectively.K_(2)O input was totally from manure.Beef cattle manure was the main organic fertilizer,which was applied by 89.2%of the farmers,with the average input rate of 25.6 t/ha.About 46.2%of the households applied 300-400 kg/ha of chemical fertilizer N,and 50.8%of the households applied 100-200 kg/ha of chemical fertilizer P_(2)O_(5).Chemical N and P_(2)O_(5) were excessively applied by 72.3%and 83.0%of growers,respectively.Diammonium phosphate and urea were the main chemical fertilizers used,accounting for 86.2%and 83.1%of the total fertilizer types,respectively.It is suggested that chemical N and P fertilizers can be potentially reduced by 26.8%and 37.1%in this region,respectively.Therefore,under the condition of lots of manure application in spring maize,it is a key countermeasure for saving costs and increasing benefits by reduction of chemical fertilizers N and P in the Southern Mountain Region of Ningxia.