Characterization of Ferrallitique Soils

Ferrallitique토양(土壤)의 특성(特性)에 관(關)한 연구(硏究)

Ferrallitique soils are real tropical soils, with an oxic B horizon such a horizon is at least 30cm thick, has > 15% clay, diffuse horizon boundaries, no weatherable minerals and a CEC of clay < 16 me per 100g. These soils are in general the real reddish or yellowish very uniform tropical clay soils with an orchric A horizon and a deep B horizon, otherwise almost characterless. The soil profile looks uniform and maybe some metres thick. It is well drained, has a good permeability and a stable structure. As there is little or no weatherable mineral, because these soils are old and exhausted of bares, natural fertility is very low. There has been a complicated process of soil formation. Intensive and continuous weathering over a very long period has resulted in leaching of bases and silica, in relative accumulation of resquioxides and in formation of kaolinitic clay. Until recently, there has been much confusion in classifing and naming tropical soils. Particularily what are now Ferralsols in the FAO scheme, and Oxisols in Soil Taxonomy. Old names of various classification system are: Lateritic soils, Latosols, Ferrallitic soils. For agriculture, these soils are important, but chemically very poor, not only because of a low CEC but also because of deficiency of bases, especially Ca, Mg, and K, strong P fixation and high exchangeable Al percentage.

Ferrallitique 토는 Orchric A층(層), Oxic B층(層)을 갖고 토색이 황갈색내지 적갈색을 띠고 풍화가 심히 진전되어 이 풍화광물이 매우 적은 토양이다. 염기가 용탈되어 토양비옥도가 매우 낮은 것이 특징이며 주점토광물은 케오리나이트이고 토양의 물리성이 양호한 토양이다. 농업적(農業的)인 면(面)에서는 앞으로 이용(利用) 가능성(可能性)이 높다.