在甘肃引黄灌区选择60 个典型玉米地，对其土壤耕层状况进行了调查分析。结果表明，甘肃引黄灌区玉米地平均耕层深度为22.5 cm，比我国土壤平均耕层(16.5 cm)高6.0 cm，犁底层平均厚度为 9.1 cm。0~40 cm土层容重在1.36 g/cm3左右，孔隙度在48.5%左右。0~45 cm土壤紧实度200～2 450 kPa，靖会灌区显著高于其他灌区，景电、兴电、刘川灌区相差不大。土壤有机质含量为12.94～15.64 g/kg，全氮含量为0.84～1.24 g/kg，碱解氮含量为47.14～60.56 mg/kg，速效磷含量为14.28～33.57 mg/kg，速效钾含量为156.50～185.84 mg/kg，除速效磷和速效钾含量较高外，其它指标均属于中等偏下水平。

Based on 60 typical corn fields, the soil plough layers and soil nutrients were investigated in Gansu Yellow River Irrigation District. The results showed that the thickness of the mean plough layer in Gansu Yellow River Irrigation District was 22.5 cm， which was 6.0 cm shallower than that of nationwide plough layer, the average thickness of plough pan was 9.1 cm. the soil bulk density of 0~40 cm layer was about 1.36 g/cm3， and the soil porosity was about 48.5%. The soil compactness of 0~45 cm layer ranged from 200~2 450 kPa， Jinghui irrigated area were significantly higher than others， Jingdian, Xingdian and Liuchuan Irrigated Areas had little difference. The soil organic matter contents ranged from 12.94~15.64 g/kg， total nitrogen ranged from 0.84~1.24 g/kg， alkaline-hydrolyzed nitrogen ranged from 47.14~60.56 mg/kg， available phosphorus ranged from 14.28~33.57 mg/kg， and available potassium ranged from 156.50~185.84 mg/kg. Except for the high content of available phosphorus and potassium， all the other indexes were in the lower middle level.

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农业部公益性行业(农业)科研专项(201503117)；甘肃省农业科学院科技创新专项(2015G AAS03)资助。