【摘 要】
：
随着复种指数的提高和单位面积产量的增加,土壤缺钾的现象日趋突出。如何加快磷钾肥的发展及其试验研究,仍然是一项急待解决的问题。1978年世界使用化肥的氮、磷、钾比例平
【机 构】
：
铁岭县农业技术推广中心,中国科学院林业土壤研究所,
论文部分内容阅读
随着复种指数的提高和单位面积产量的增加,土壤缺钾的现象日趋突出。如何加快磷钾肥的发展及其试验研究,仍然是一项急待解决的问题。1978年世界使用化肥的氮、磷、钾比例平均为1:0.6:0.5。而施肥水平较高的国家,
With the improvement of multiple cropping index and the increase of yield per unit area, the phenomenon of potassium deficiency in soil has become increasingly prominent. How to speed up the development of P and K fertilizer and its experimental research is still an urgent problem to be solved. In 1978, the proportion of nitrogen, phosphorus and potassium used by the world fertilizers averaged 1: 0.6: 0.5. Countries with higher fertilization levels,
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