农田土壤养分变异与施肥推荐

采用差分式GPS定位的方法 ,对山东省青州市王母宫乡王七村 5.47hm2的地块进行了50m50m的网格式取样 ,用土壤系统研究法对其大、中、微量元素进行了分析。结果表明 ,土壤中的营养元素均存在着一定的变异。根据土壤养分的抽样分布 ,可将土壤养分分为两种类型 ,一为偏斜型营养元素 ,主要有氮、磷、硫等 ;其它属另一类 ,为非偏斜营养元素。造成土壤营养元素偏斜的主要原因是施用化学肥料。对施肥较多 ,且施肥历史较长的营养元素 ,在进行测土推荐施肥时 ,不仅要考虑大田的平均养分含量 ,还应考虑土壤的养分的空间变异状况 ;对非偏斜元素的施肥推荐以大田平均值即可

Variability of soilnutrients in field and fertilizer recommendation

The variability of soil nutrients was studied by grid samplingusing D GPS in the Wangqi village of Qingzhuo City, Shandong Province. It indicated tha t the soil nutrients had variability in field. Based on the sampling distributio n , the nutrients were divided to two classes. One was called declining nutrients , such as nitrogen, phosphorus and sulfur. The other called non-declining nutri en ts. The reasons of declining were mainly caused by supplying of chemical fertil i zer. For the large amount and longer history applying nutrients, the reco mmendati on must be based on the spatial variability of soil nutrients, the others can be based on the average testing values of the field.