| dc.description.abstract | 本報告分從成土因子與其主要特徵討論本省紅棕壤、黃棕壤及紅黃色灰化土之生成與土壤分類之明確地位，所用材料為前人經分類鑑別之上列土壤計共49土系之土壤剖面，根據國內外過去研究資料，研訂鑑別此3土類之主要特徵，以樣對上列49土系之特徵，分別其歸屬，結果摘要如下：
（一）現代之本省平地氣候，無法解釋本省紅棕壤之生成，低山丘陵地帶氣候適於灰土化作用之進行，因而本省之紅棕壤已經和緩的灰土化，而黃棕壤及紅黃色灰化土，除具備磚紅土化作用外更具不一之灰土化作用，黃棕壤則更具黃鐵礦化作用，亦有部分係母質之影響，為新成之土壤者。
（二）頗多土壤學者研究紅棕壤之生成，謂非現世氣候下之產物，而係上新世至中新世風化之遺物，本省所發見之紅棕壤，不論東西南北，多發育於更新統臺地礫石層上，頗符合國外之理論。
（三）美農部第七次土壤分類草案以鹽基性火成岩方能生成紅棕壤，惟本省頗多水成岩及變質岩母質亦生成紅棕壤。
This report includes the discussion of the genesis and clarification of classification of reddish brown latosols, yellowish brown latosols and red yellow podzolic soils on basis of soil forming factors and some major characteristics. In view of these general findings some evidence of these three groups being found in the past is clarified. It may be summarized as follow:
1. It is hard to explain the genesis of the reddish brown latosols from the recent climatic data of the lowland in Taiwan. As podzolization is taking good in process in the rolling hill zone, the reddish brown latosols have been podzolized gradually. Laterization and Podzolization are both being found on yellowish brown latosols and red-yellow podzolic soils, and the former have modified with some limonization, but some of them are affected by its parent material, so that it may be called as young soils.
2. The genesis of reddish brown latosols is not the result of recent climate, but its parent material was derived from the weathering rDsidual products of the Plistocene and Miocene age. The reddish brown latosols being found in Taiwan were mostly developed on the pleistocene terrace table land. It confirms the .theory of the pedologists abroad.
3. According to the 7th approximation of soil classification U.S.D.A. 1960, as rhodochrults which have been called reddish brown latosols, they are drived from primary basic igneous rocks, but many of reddish brown latosols of Taiwan are developed from sedimentary rocks and metamorphic rocks also. | en_US |
