The content of potassium was determined in the whole soil and in fractions >5, 1–5, and <1 μm in extracts of 1 M NH₄OAc, 2 M HCl, and hot 10% HCl in the (AO)EL horizon of a podzolic soil in the rhizosphere of Norway maple (Acer platanoides L.) and from the bulk soil. It was established that the content of exchangeable potassium is significantly higher in the rhizosphere with a higher amount of organic matter as compared with the bulk soil. Based on the existing gradations of supply of tree cultures with this element, the soil of the rhizosphere refers to the gradation of increased level of supply, and the bulk soil is moderately provided with potassium. In the soil of the maple rhizosphere, as compared with the bulk soil, there is more hardly hydrolysable potassium, which can be explained by the transition of the element to the acid extract from the fine and poorly crystallized mica and illite particles. It is assumed that the increased content of these minerals in the rhizosphere is due the intensification of the processes of illitization and physical disintegration of mica and illite particles occurring in coarser fractions.

中文翻译：

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坡地土壤中挪威枫树根际的可提取钾化合物

在（AO）EL视界中，测定了整个土壤中和> 1 M NH ₄ OAc，2 M HCl和热10％HCl的提取物中> 5、1-5和<1μm的钾含量。挪威枫根际（Acer platanoidesL.）和散装土壤。已经确定，与块状土壤相比，在根际中具有较高有机质含量的可交换钾含量明显更高。根据具有此元素的树木文化的现有供应等级，根际土壤是指供应水平增加的等级，而散装土壤则适度提供钾。与块状土壤相比，在枫树根际土壤中，钾的水解性更高，这可以通过元素从细小且结晶性差的云母和伊利石颗粒向酸提取物的过渡来解释。