Abstract
Three pedons were surveyed to clarify chemical properties and mineralogical characteristics of tea garden soils in the Cheju Island, Korea. The results are as follows: 1) Soil color of the soils in the Cheju Island were black or brownish black. The gravel contents of the soils in the three pedon were very high (10-70%), and the soil textures were sandy loam. 2) All three pedons surveyed were classified into Andosols, which had dark colored and high humic A horizons, the phosphate absorption coefficients of 1500 or more and large amounts of acid oxalate extractable Al and Fe (Al_o and Fe_o). 3) The soil pH (H_2O) under the tree crown were lower than those in the inter-row. The exchangeable Al were high in the soil under the tree crown, reflecting low pH of those soils. Furthermore, the exchangeable cation was low in the soil under the tree crown, because of the strong leaching and the lacking of dolomite application. 4) It was estimated that the tea garden soils in the Cheju Island contain not only allophane but also chrolite, 2:1-2:1:1 intergraded minerals and 1:1 type clay mineral by X-ray diffraction analysis.
