Because the content of insoluble residue is a little in limestone, it is a problem for many years what is the parent materials of dark red soils distributed on limestone. In this paper, it was investigated that properties and uniformity of parent materials in the dark red soils developed over Kinshousan, Ohgaki city, and Maesato, Ishigaki island. The outline of the results are summarized as follows: The indissoluble residue after the treatment with 1 mol L^<-1> acetic acid was 6 and 318g kg^<-1> in the limestones in the Kinshousan soil and the Maesato soil, respectively. It suggested that main materials of Kinsyousan soil is besides limestone. On the other side, it was estimated that limestone was an important parent material in the Maesato soil. The ESR-signal intensity associated with the oxygen vacancies in silt-sized quartz showed that fine quartz in both soils was derived from eolian dust. However, the limestone also affected the physical and chemical properties, and clay mineralogical composition. Moreover, the clay mineralogical composition showed a characteristic of pedogenesis under the climate in which each soil had formed. Furthermore, the influence of the Akahoya tephra was confirmed in the Kinshousan soil, too. Therefore, the Kinsyousan soil is a dark red soil that is derived from not only eolian dust but limestone and Akahoya tephra influenced of pedogenesis under the warm temperate climate. The Maesato soil is a dark red soil that is derived from limestone and eolian dust infuluenced of pedogenesis under the humid sub-tropical maritime climate.

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The ESR-signal intensity associated with the oxygen vacancy in the silt sized fine quartz and the clay mineral composition were examined, in order to investigate the influence of eolian dust on the parent materials in two Red-Yellow soils developed on the bedrock of Tertiary sediments and two Dark Red soils on the bedrock of the Tertiary Ryukyu limestone, in Yonaguni island. The results summarized as follow: In the A, Bw1 and BC horizon of a Red-Yellow soil, Kubura (KUB) soil, ESR-signal intensity of fine quartz in the silt fraction was above 10 and very high value, and suggested the influence of eolian dust brought from the Precambrian area in the southern part of China on the parent materials in this soil during MIS2. In two Dark Red soils, Sonai (SON) and South-meadow (MIN) soil, the ESR-signal intensities of silt sized fine quartz in the A and B horizon were also very high and suggested the eolian dust from Precambrian area in the southern part of China. On the other hand, the ESR-signal intensities of fine quartz in the A and B horizons in a Red-yellow soil, Urabu (URA) soil were slightly low and the parent materials in this soil were the mixture of eolian dust from the Precambrian area in the southern part in China and autochthonous Tertiary bedrock. The parent materials in four reddish soils developed on the Tertiary bedrock in Yonaguni island were derived from the eolian dust brought from the Precambrian area in southern part of China during MIS2, Last glacial Maximum. While a small amount of the autochthonous Tertiary materials were slightly mixed to the parent materials in these soils. This result obtained from the ESR-signal intensities of fine quartz were harmonized with the clay mineral composition in these soils.

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Rehabilitation of tropical rainforest on degraded forestland requires sufficient knowledge of soils. However, in Malaysia, the empirical data of soil properties on degraded forestland under rehabilitation are still lacking, In order to get fundamental information for evaluating the performance of rehabilitation program under various planting techniques on such degraded forestland, firstly, soil profiles of the planted forest of degraded forestland and adjacent natural forest need to be investigated. This study was conducted to elucidate the soil morphology, mineralogical and physico-chemical properties of degraded forestland under rehabilitation in two major forest types at Bukit Kinta and Chikus forest reserves in Perak, Peninsular Malaysia, representing hill and lowland dipterocarp forests, respectively. Shorea leprosula and Shorea parvifolia were planted at both sites. At the Bukit Kinta site, three soil profiles were prepared at two planted forests and one natural forest of hill-dipterocarp. At Chikus site, three soil profiles were examined under one planted forest, one mixed plantation with Acacia mangium and one natural forest of lowland dipterocarp. The soils at Bukit Kinta were derived from granite and showed clayey texture, while those in the Chikus showed relatively sandy texture resulting from their sandy parent materials and fluvial deposits. Soil profiles at Bukit Kinta were relatively uniform, while those in the Chikus site were greatly fluctuated upon micro-topography including water stagnant condition during rainy season. Based on the mineralogical and charge characteristics, the soils in the planted forests and natural forest in both study sites were strongly weathered but had not yet reached the ultimately weathered phase. The clay mineral composition was dominated by kaolin minerals (Bukit Kinta) and gibbsite (Chikus), with almost devoid of 2:1 type clay mineral, while both Al and Fe oxides were low. The soils in both sites were acidic due to the presence of a high amount of exchangeable Al which concomitantly increased the level of Al saturation. The variable negative charges derived from organic matter can potentially play an important role in cation retention, but its contribution under field conditions on the study sites were relatively small due to strongly acidic conditions. The plantation of the trees for rehabilitation (12 and 14-year old) could not sufficiently restore the soil organic matter to the same level as that of the natural forest caused by disturbance preceding the project. It can be concluded that the fertility status of the soils at planted forests were generally lower as compared to the natural forest in both study sites.

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The ESR-signal intensity associated with the oxygen vacancy in the fine quartz and the clay mineral composition were examined in order to investigate the influence of eolian dust on the parent materials in two fine texured Brown Forest soils developed on the bedrocks of the Neogene Tertiary tuffeceous rocks, near Cape Nyudo in Oga peninsula. The results were summarized as follows: The high values more than 10 unit in the ESR-signal intensity of fine quartz in these two soils suggested that large amount of the eolian dust brought from the Precambrian sediments area influenced severely on the parent materials in A to Bw horizons of these soils and this eolian dust had been brought by NW-monsoon during the Last Glacial Maximum(MIS2, 24-11 thousand years ago). On the other hand, the autochthonous Mioce volcanogenous rocks were also influenced slightly on the parent materials in this soil. Moreover, the influence of small amount of the Tephras such as K-Ah also observed in these two soils. Moreover, the parent materials in the 2BC-horizon of the Anzenji soil, which was a paleo-red soil, were also influenced severely by the eolian dust derived from the Precambrian rocks in the northern part of Asia continent, and done considerably by the autochthonous Miocene volcanogenous rocks.

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The ESR-signal intensity associated with the oxygen vacancy in the fine quartz and the clay mineral composition were examined, in order to investigate the influence of eolian dust brought from the northern Asia continent on the parent materials in a fine textured soil developed on the bed rock of the Tertiary and quaternary rocks, near Cape Saruyama in Noto Peninsula. The results were summarized as follows: The high values, more than 10 unit, in the ESR-signal intensity of fine quartz in this soil suggested that large amount of the eolian dust brought from the Precambrian sediments area influenced severely on the parent materials in this soil, and this eolian dust had been brought from Precambrian sediments area in the northern part of Asia continent by the winter NW-monsoon during the Last Glacial Maximum, MIS2 (24-11thousand years ago), when the inland in Asia continent had been dried severely. On the other hand, the autochthonous materials were also influenced slightly on the parent materials in this soil. Moreover, the influence of small amount of the Tephras such as K-Ah and AT also observed on this soil materials.

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The ESR-signal intensity associated with the oxygen vacancy in the fine quartz and the clay mineral composition were examined, in order to investigate the influence of eolian dust on the parent materials in a fine-textured Brown Forest soil developed on the bedrock, Tertiary dacitic Pyroclastic rock, near the top of Mt. Horyu in Noto peninsula. The results were summarized as follows: The high values, more than 10 unit, in the ESR-signal intensity of fine quartz in this soil suggested that, large amount of the eolian dust brought from the Precambrian sediment area influenced severely on the parent materials in this soil, and this eloian dust had been brought from Precambrian sediments area by NW-monsoon during the Last Glacial Maxmum, MIS2 (24-11 thousand years ago). On the other hand, the autochtonous Terciary bedrock was also influenced slightly on the parent materials in this soil. Moreover, the influence of a small amount of the Tephra such as A-Th was also observed in this soil.

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