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华北土壤一直被认为钾素含量高.农业生产不需施用钾肥。通过第二次土壤普查发现,我市土壤速效钾含量并不高,一般含量在60-120ppm之间。其中含量在100ppm以下的面积占耕地面积的70.84%.只相当于全国土壤速效钾养分等级的第四级。尤其是近几年随着农作物产量的提高,以及氮、磷化肥施用量的不断增加,一些地区土壤钾素不足已成为障碍农业生产的限制因子。为此我们从1980年开始在重点县进行了
North China soil has always been considered high potassium content. Agricultural production without applying potassium fertilizer. Through the second soil census found that the soil available potassium content is not high, the general content of 60-120ppm. The content below 100ppm accounts for 70.84% of the cultivated land area, which is only equivalent to the fourth grade of the national soil available potassium nutrient grade. In recent years, with the increase of crop yield and the increasing application of nitrogen and phosphorus fertilizers, the shortage of potassium in some areas has become a limiting factor for agricultural production. For this reason we have been in key counties since 1980