九宫山土壤剖面中黏土矿物的组成特征

Characteristics of Clay Minerals in Soil Profiles of Jiugong Mountain

以湖北省九宫山的4种垂直地带性土壤为对象,研究其剖面层次的黏土矿物组合和铁、铝氧化物的特征,揭示山地土壤中黏土矿物的变化特点。结果表明,随海拔升高,土壤中黏土矿物类型从以高岭石为主,逐渐变为以14.0?矿物、伊利石及三水铝石为主,有从1︰1型向2︰1型矿物过渡的趋势;不同层次的土壤中黏土矿物类型和相对含量变化明显;土壤随垂直高程的升高,其中游离态铁、铝减小,非晶形和络合态铁、铝增加,各种形态铁、铝氧化物的总量也增加。

The composition characteristics of clay minerals and iron-aluminum oxides at different horizons of soil profiles in the vertical zonal soils of the Jiugong Mountain in Hubei Province were studied to reveal the changes of clay minerals in mountain soils. The results indicated that the content of kaolinite was abundant in soil at lower altitude, whereas the majority was 14.0？ minerals, illite and gibbsite at higher altitude. With the increase of altitude, there was a transition trend of clay minerals from 1：1 to 2：1 types. The changes of types and relative contents of clay minerals in soils were obvious at different horizons in soil profiles. With the increase of altitude, the contents of free iron-aluminum oxides decreased but those of amorphous and complex iron-aluminum oxides increased in clays, and the total amounts of iron-aluminum oxides in different forms were also increased.