抄録
This study was conducted on a model made under the following conditions. Groundwater level was set at approximately one meter. Plow layer and plowsole were closed system percolation and made into a reducing layer. Subsoil above the groundwater level was open system percolation and made into an oxidation layer. Subsoil below the ground water level was closed system percolation and was made into a reducing layer. This model was used to evaluate eluviation and illuviation of soluble ions in percolating water. Findings are listed as follows.
1.Iron ion in the percolating water were found in the reducing layer, but the concentration of the iron ion was reduced in the oxidation layer. Manganese ion was found in both the oxidationlayer and the reducing layer.
2. In the closed system percolation concentration of iron ion in percolating water can affected concentrations of calcium, magnesium, sodium and potassium ion. when concentration of iron ion is higher, the ion cconcentrattion of calcium, magnesium, sodium and potassiumin start to increase.
3. Nitrogen ion concentration in the form of ammonium ion was high in the plow layer and plowsole, and the concentration was considerably lower in the subsoil. However, nitrate ion concentration was low in plow layer and plowsole, and increased sharply in the open system percolation (oxidation layer) in upper subsoil, and lowered considerably in the closed system percolation (reducing layer) of the lower subsoil. As the above results demonstrate that percolation systems were found to be an important factor for eluviation and illuviation of soluble ions.
