皖南山地主要土壤的特征和分类问题

本文研究了皖南山地主要土壤的特征和分类。结果表明,本区土壤风化和淋溶作用强,富铝化特征明显,且随海拔高度的增加,土壤特征有差异。海拔600-700m以下的土壤,B层颜色以红棕色和亮红棕色(5YR5/6-5/8)为主,粉砂/粘粒值小于1.00,风化淋溶系数小于0.35,盐基饱和度小于35%,粘粒SiO₂/Al₂O₃多小于2.4。粘粒矿物以高岭石为主。氧化铁的活化度和络合度低,表层HA/FA小于0.35。该类土壤定为黄红壤(红壤土类中的一个亚类)。海拔600-700m以上的土壤,B层颜色以黄色(2.5Y8/6)和亮黄棕色(10YR6/6-6/8)为主,粉砂/粘粒值大于1.00,风化淋溶系数大于0.35,盐基饱和度小于35%,粘粒SiO₂/Al₂O₃一般大于2.3。粘粒矿物以蛭石和高岭石为主,并有较多的三水铝石出现。氧化铁的活化度和络合度高,表层HA/FA值0.35-0.75。该类土壤定为黄壤。从粘粒矿物组成和SiO₂/Al₂O₃,判断,皖南山地上部不存在山地黄棕壤和山地棕壤。土壤垂直带谱主要由黄红壤和黄壤构成。

CHARACTERISTICS AND CLASSIFICATION OF MAJOR SOILS IN MOUNTAINOUS AREA OF SOUTH ANHUI

This paper deals with the characteristics and classification of major soils in the mountaiainous area of the southern Anhui Province. The soils in the area are strongly weathered and leached, with obvious enrichment of alumina. The characteristics of soils varied with the altitude. In B horizons of the soils distributed below 600-700m above sea level, the soil colour is reddish brown or bright reddish brown (5YR5/6-5/8), the ratio of silt/clay smaller than 1.00, the coefficient of weathering and eluviation lower than 0.35, the base saturation lower than 35% and the silica-alumina ratio of clay smaller than 2.4. Kaolinite is dominant in clay minerals. Both the degree of activation and the degree of complex of iron oxide are low. HA/FA in surface soils is smaller than 0.35. The soils belong to yellow-red soil (a subgroup of red aoil).