Study on mathematical model for relationships between soil nutrients and wheat yield in dry land in Hebi | 鹤壁市旱地小麦土壤养分与产量的数学模型研究

Chinese. 为探讨鹤壁市旱地小麦土壤养分与产量之间的数量关系，指导农民合理施肥，依据鹤壁市旱地43个有代表性的样点土壤全氮含量、速效磷含量和有机质含量测试数据，建立了土壤养分与产量之间的数学模型。结果表明，鹤壁市旱地土壤养分空间变异以速效磷为最大，属强变异，变异系数为72.77％，说明不同农户在施用磷肥上存在较大差异；土壤全氮含量和土壤有机质含量为中等变异，变异系数分别为24.59％和24.79％；在土壤有机质保持在样点平均水平（14.6 g/kg）的前提下，随着土壤全氮含量的增加，小麦产量呈现“低-高-低-高”的阶段性变化趋势；随着土壤速效磷含量的增加，小麦产量则呈现“低-高-低”的阶段性变化趋势；土壤养分效应函数解析认为，与最高产量相应的土壤全氮含量为1.22 g/kg，速效磷含量为34.33 mg/kg；与最佳经济产量相应的土壤全氮含量为1.2 g/kg，土壤速效磷含量为31.86 mg/kg。

English. To explore the relationships between soil nutrient and yield of winter wheat in dry land in Hebi City, guiding peasants to rationally fertilize the soil, according to 43 representative test samples of soil total nitrogen content, available phosphorus content and organic matter content in dry land in Hebi city, a mathematical model among soil nutrients and yield was established which was up to the very significant level. The results indicate that the space variation of available phosphorus in soil nutrients in Hebi is for maximum, belonging to strong variation, with the variation coefficient for 72.77%, which shows that there is a bigger difference in application of phosphate fertilizer in different farmers, and soil full nitrogen content and soil organic matter content for medium, variation coefficient respectively for 24.59% and 24.79%; On the premise of maintaining soil organic matter being in sample average level (14.6 g/kg), as the increase of soil full nitrogen content, wheat yield is rendered the staged changes trend of low-high-lowmhigh; while with the increase of soil available phosphorus content, wheat output is rendered the periodic trend of low-high-low. According to the view of effects of soil nutrient function, soil total nitrogen content corresponding to the maximum production capacity is 1.22 g/kg, available phosphorus content 34.33 mg/kg. And the soil total nitrogen content corresponding to the best economic production is 1.2 g/kg, soil available phosphorus content 31.86 mg/kg Compared with the usual fertilization model, the mathematical model among the soil nutrients and the yield has the clear advantage of targeted, and can achieve a block corresponding to a fertilization mentoring programme.