摘要
本文对采自我国白浆土主要分布区的四个典型剖面的机械组成,化学性质及元素地球化学分异特征进行了研究。结果表明,所研究的四个剖面从以>0.002mm的颗粒为基础计算的非粘粒粒径在剖面中的分布、土壤的硅铝率、铝钾镁率以及以非粘粒为基础计算的土体TiO_2含量来衡量,母质是同源的;在成土过程中,粘粒由白浆层向淀积层淋淀,形成了两层在机械组成上的“双层性”,而不是母质两次沉积的结果;元素地球化学分异特征是:SiO_2和MnO在白浆层中富集,Fe_2O_3在淀积层中富集,Al_2O_3的富集因成土条件不同而异;Fe_2O_3、MnO、Al_2O_3反TiO_2向粘粒中富集,SiO_2向粗颗粒中富集;白浆土中粘土矿物似有微弱的破坏作用。
Four typical profiles of albic soils from the main distribution areas in China were collected to study for mechanical composition, chemical properties and geochemical elemental variability of albic soils. The main results are summarized as follows:1. The particle size distribution of the non-clay fraction and soil TiO_2 content calculated on the basis of >0.002 mm soil particles, the SiO_2/Al_2O_3 of soil and Al_2O_3(K_2O+MgO) of non-clay fraction proved that each profile has a uniform parent material.2. The mechanical composition of albic soil has a property of 'double layers'. The argillie horizon contains much more clay than the albic horizon. The ratio of clay in the argillic horizon to that in the albic horizon is >1.2.3. During the soil-forming process, clay moves from the albic horizon to argillic horiZon,which, rather than the lithologically uncontinuous deposition of parent material, results in the 'double layers'.4. The properties of geochemical elemental variability are that SiO_2 and MnO were enriched in the albic horizon while Fe_2O_3 in the argillic horizon; Fe_2O_3, MnO, TiO_2 and Al_2O_3 were enriched in clay, but SiO_2 in the non-clay fraction.
出处
《土壤学报》
CAS
CSCD
北大核心
1993年第3期274-288,共15页
Acta Pedologica Sinica
基金
国家自然科学基金
关键词
白浆土
机械组成
地球化学分异
Albic soil
Mechanical composition
Chemical properties
Geochemical elemental variation
