我国南方酸性土壤中的1. 4nm 过渡矿物(英文)

THE 1. 4nm INTERGRADE MINERAL OF ACID SOILS IN THE SOUTHERN CHINA

本文讨论了我国南方不同纬度(北纬32°-19°)、不同母质、不同海拔高度的酸性土壤中1. 4nm 过渡矿物的分布、形成条件及其存在对土壤性质的影响。1) 分布特点是:①黄棕壤中的1. 4nm 矿物主要是蛭石,只有淋溶作用较强的酸性黄棕壤中才含有1. 4nm 过渡矿物。北亚热带山地、山麓土壤中的1. 4nm 矿物主要是蛭石,但随海拔升高,蛭石含量迅速减少,1. 4nm 过渡矿物则从无到有、从少到多。②红壤、赤红壤中的1. 4nm 矿物主要是1. 4nm 过渡矿物,第四纪粘土母质发育的红壤中常伴生有少量蛭石,中-南亚热带山地土壤,随海拔升高,土壤中1. 4nm 过渡矿物含量增高、热稳性增强。③花岗岩发育的砖红壤中不含1,4nm 矿物,而玄武岩发育的砖红壤中含有1. 4nm 过渡矿物,热带山地,山麓土壤中一般不含1. 4nm 矿物,五指山海拔1200米以上才出现1. 4nm 过渡矿物。2) 1. 4nm 过渡矿物的形成条件,可归纳为:①适宜的土壤矿物风化强度,土壤中含有2:1型膨胀性矿物。②土壤呈酸性反应。③土壤有机质含量不是太高。④其形成随地区气候和母质不同而不同。3) 含1. 4nm 过渡矿物的土壤粘粒的硅铝率、阳离子交换量、比表面等都比含蛭石的土壤低,而土壤的交换性铝的含量、固磷量和土壤可变负电荷量占负电荷总量的比例则相反。

The distribution and condition of 1. 4nm intergrade mineral development and its implication on soil roperties for soils in southern China were discussed.1. In yellow brown soil,1. 4nm mineral is generally solely ermiculite and 1. 4nm intergrademineral appears only in soil with a pH value below 5. 6. In the red soil and lateritic oil,1. 4nm mineralis mainly 1. 4nm intergrade mineral,with scant or without vermiculite.There is a little 1. 4nm ineralin the latosol developed from basalt.2. The condition of 1. 4nm intergrade mineral formation may be ummarized as follows:①adequate weathering of soil mineral,② acidic soil reaction.③ not too high content of soil rganicmatter.④ its formation varies with regional climate and parent material.3. The ratio of SiO_2/R_2O_3 and SiO_/Al_2O_3,the value of CEC and the surface area of clay fractionin soils dominant in vermiculite are higher than hose dominant in 1. 4nm intergrade mineral.But theamount of exchange-Al and the percentage of variable negative harge from total negative charge in theformer are lower than those in the latter.