不同母质发育的东北黑土的粘粒矿物组成研究

A Study on Clay Minerals from Different Parent Material of Black Soil

东北黑土的成土母质主要是第四纪沉积物,在对红土母质和黄土母质上发育的两种东北黑土剖面土壤进行小于2μm粘粒的化学组成和XRD衍射分析基础上,研究这两种母质上发育的东北黑土的粘粒矿物组成。结果表明红土母质上发育的东北黑土风化脱硅作用较强,以1—1型或2—1型粘粒矿物为主,主要含有伊利石、蛭石、高岭石,上层土壤粘粒中含有少量绿泥石,母质层含有大量的蒙脱石,不含有绿泥石。在成土过程中,伊利石大量存在,少量绿泥石逐渐形成,蒙脱石向蛭石转化;黄土母质上发育的东北黑土以2—1型粘粒矿物为主,主要含有伊利石、蛭石、高岭石、少量的绿泥石,母质层粘粒中含有长石,经过脱硅作用逐渐消失,有些土壤的母质层粘粒中也含有蒙脱石,粘粒矿物分布相对均匀,矿物间的转化和演化相对简单。

Parent material of black soil in the Northeast China is mainly quaternary sediment.Based on chemical composition and XRD of two kinds of soil particles（less than 2 μm in diameter） from black soil profile,laterite parent material and loess parent material,the results show that the black soil in Northeast China developed from laterite parent material has strong desilication.The clay minerals are 1-1 and 2-1 types,mainly containing illite,vermiculite,and kaolinite.Soil particles from the upper soil have low contains of chlorite.Parent material has high content of montmorillonite but without chlorite.During the process of soil formation,it existed high contents of illite,with slight chlorite gradually formed,and montmorillonite was converted to vermiculite.Black soil particles developed from the loess parent material are 2-1 type clay minerals,containing illite,vermiculite,kaolinite,with slight chlorite.Some parent material contains feldspar.Feldspar in the soil minerals gradually disappeared after desillication.Some parent material contains montmorillonite.Distribution of soil particle developed from the loess parent material is relatively even,and conversion and evolution among minerals are relatively simple.