土壤肥力差异对冀中南山前平原与低平原夏玉米产量的影响

评价区域土壤基础肥力差异、明确土壤肥力对作物产量的影响，对农田土壤培肥和优化养分管理具有重要意义。本研究利用2005—2013年在冀中南山前平原和低平原区开展的967组“3414”夏玉米田间试验，系统分析了河北冀中南山前平原与低平原基础地力差异对玉米产量的影响。结果表明：冀中南山前平原土壤有机质、全氮和有效磷均高于低平原，速效钾含量略低于低平原；山前平原玉米基础产量6133 kg/hm²，高于低平原的5815 kg/hm²。基础地力贡献率分别为71.2%和69.0%；山前平原在不施肥条件下获得高产的土壤有机质、全氮、有效磷和速效钾最小值分别为14.9 g/kg、1.07 g/kg、19.1 mg/kg和127 mg/kg，低平原则为16.0 g/kg、0.76 g/kg、18.8 mg/kg和106 mg/kg。影响山前平原玉米基础产量的主要肥力因子是土壤速效钾和有效磷含量，影响程度分别为38.6%和24.8%；影响低平原玉米基础产量的主要因子是土壤有机质和有效磷含量，影响程度分别为45.0%和32.2%。本研究表明，山前平原土壤培肥要以稳定和提高土壤速效钾和有效磷含量为主攻方向，低平原则要以提高土壤有机质和有效磷含量为目标。

Effects of Soil Fertility Difference on Summer Maize Yield in Piedmont Plain and Low Plain in Central and Southern Hebei

Evaluating the regional differences of basic soil fertility and clarifying the impact of soil fertility on crop yield are of great importance to improving farmland soil fertility and optimizing nutrient management. In this study, 967 groups of ‘3414’ summer maize field trials, which were conducted in the piedmont and low plains of central and southern Hebei Province from 2005 to 2013, were used to analyze the impact of the difference in basic soil fertility on summer maize yield. The results showed that the soil organic matter, total nitrogen and available phosphorus in the piedmont plain of central and southern Hebei were higher than those in the low plain, and the available potassium content was slightly lower. The basic maize yield for piedmont and low plains were 6133 kg/hm² and 5815 kg/hm², respectively, and the soil fertility contribution rates were 71.2% and 69.0%, respectively. The minimum values of soil organic matter, total nitrogen, available phosphorus and available potassium that could support high yield in the piedmont plain without fertilization were 14.9 g/kg, 1.07 g/kg, 19.1 mg/kg and 127 mg/kg, respectively, and those in low plain were 16.0 g/kg, 0.76 g/kg, 18.8 mg/kg and 106 mg/kg, respectively. The main fertility factors affecting the basic maize yield in the piedmont plain were the soil available potassium content and available phosphorus content, with the influence degree of 38.6% and 24.8%, respectively; the main factors affecting the basic maize yield in the low plain were the soil organic matter content and available phosphorus content, with the influence degree of 45.0% and 32.2%, respectively. The study suggests that the soil fertility improvement in piedmont plain should focus on stabilizing and increasing soil available potassium and available phosphorus contents, while low plain areas should focus on increasing soil organic matter and available phosphorus contents.