长期施用钾肥对草甸土钾素形态的影响

通过连续13年的钾肥定位试验，研究了施钾对草甸土耕层土壤钾素各形态含量和比例的影响。结果表明，长期施用钾肥较不施钾处理可以增加耕层土中水溶性钾、非特殊吸附钾、特殊吸附钾、非交换性钾的含量和在全钾中的比例，施钾量增加促进了这种状况，同时降低了矿物钾在全钾中的比例。随土层加深，大部分处理的水溶性钾、非特殊吸附钾、特殊吸附钾和非交换性钾含量和比例随之降低，而矿物钾和全钾含量相应处理却随之升高，其中施钾处理的效果明显。

Effect of long-term K application on potassium forms in meadow soil

Based on the long - term field experiment of K application on meadow soil, the effect of K fertilizer apphcation on the content and proportion of K was discussed. The result showed that long - term K application could increase the content and proportion of water - soluble K, non - specially adsorbed K, specially adsorbed K, non - exchangeable K in the plough layer, and decrease the proportion of mineral K in the same time. Along with the layer going to deeper, the content and proportion of water- soluble K, non - specially adsorbed K, specially adsorbed K, non - exchangeable K in most treatments decreased, and the effect was more distinct in the treatments of K application, but mineral K and total K behaved the opposite result. K fertilizer application could increase corn grain yield remarkably.