The absorption coefficient of soils was measured by using ammonium or phosphorus in the past and potassium was scarcely used.
We attempted to measure the K-absorption capacities of 50 soils in Shimane prefecture, and considered of the correlation of the K-absorption capacity, to humus and clay of soils.
The correlation coefficient between the K-absorption capacity and the humus was -0.10±0.09, and in the clay 0.34±0.08.