长白山及五大连池火山灰土电荷零点的初步研究

Characters Of Zero Point Of Charge Of Andisols In Changbai Mountain And Wudalianchi

本文采用电位滴定法测定了长白山、五大连池火山灰土的电荷零点(ZPC),分析了影响电位滴定曲线形状、ZPC高低及其位移的因素。研究结果表明,两地火山灰土的ZPC均以C层最高,B层次之,A层最低;长白山剖面A、Bw、C三层的ZPC分别为2.65,4.20,4.35;五大连池削面A、Bw、C三层的ZPC分别为3.20,3.25,3.40;两地火山灰土的ZPC都有不同程度的位移,即ZPC均落在滴定零点(ZPT)的酸侧,说明两地火山灰土均为恒表面电位型胶体和恒表面电荷型胶体的复合体系,两地土壤不同层次中ZPC位移量大小顺序均为:A层>Bw层>C层。

The characters of the zero point of charge (ZPC) of Andisols in Changbai mountain and Wu-dalianchi were studied in the current paper. The results indicated that the values of ZPC rised from A horizons to C horizons in both soils. The ZPC values were 2. 65, 4.20, and 4. 35 in A, Bw, and C horizons for Changbai mountain soil and 3. 20, 3. 25, and 3. 40 in the same horizon sequence for wudalianchi soil. There were some what degree displacement of ZPC from the the values of Zero Point Of Titration for both soils, whose follow the trend of A horizon > Bw horizon > C horizon. It stated that the colloids of both soils belong to the compound type of constant surface charge and constant surface potential soil colloids.