应用Multi-Langmuir模型评价土壤的表面电荷特性  

EVALUATION OF SURFACE CHARGE CHARACTERISTICS OF SOILS USING MULTI-LANGMUIR MODEL

作　　者：王代长[1,2] 蒋新[2] 贺纪正[3] 卞永荣[2] 饶伟[1] 

机构地区：[1]河南农业大学资源与环境学院,郑州450002 [2]土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所),南京210008 [3]中国科学院生态环境研究中心,北京100085

出　　处：《土壤学报》2009年第4期611-616,共6页Acta Pedologica Sinica

基　　金：土壤与农业可持续发展国家重点实验室开放基金(0751010004);国家杰出青年科学基金(No.40325001);河南农业大学创新基金(2006-CX-017)联合资助

摘　　要：用返滴定技术测定土壤的可变电荷量(Qv),应用Muti-Langmuir模型评价土壤的表面电荷特性。结果表明,黄壤和黄棕壤可变电荷量的变化范围在0～45cmolkg-1,红壤为0～21cmolkg-1,砖红壤和赤红壤为0～14cmolkg-1。可变电荷量(Qv)依赖土壤悬液的pH,3点位模型能很好地描述6种土壤的可变电荷量随pH的变化关系;黄壤、黄棕壤、湖南红壤、江西红壤、赤红壤和砖红壤的pK1分别为4.45、4.46、4.76、4.62、4.66和4.74,可变电荷量Qv1分别为11.7、9.64、9.31、7.14、4.86和5.95cmolkg-1。黄壤和黄棕壤pK1较红壤、砖红壤和赤红壤约低0.3。pK1与ZPC呈现极显著的线性关系,可变电荷量(Qv(i))与有机质含量呈极显著的正相关。Soil surface charge was measured with the potentiometric back-titration technique, and its characteristics evaluated with the Multi-Langmuir model. Results show that the variable surface charge of yellow soil and yellow brown soil varied in the range of 0 -45 cmol kg^-1, of red soils in the range of 0 - 22 cmol kg^-1 and of latosolic red soil and latosol in the range of 0 - 14 cmol kg^-1, depending on pH of their respective soil suspension. The muhi-Langmuir model was used to simulate surface charge, assuming that the three-site model might be adopted to describe the relationship of variable charge with pH. Of yellow soil, yellow brown soil, Hunan red soil, Jiangxi red soil, latosolic red soil and latosol, pK1 was 4.45,4.46, 4.76, 4.62, 4.66 and 4.74, respectively ; and Qvl was 11.65, 9.64, 9.31,7.14, 4.86 and 5.95 cmol kg^-1 respectively. Yellow soil and yellow brown soil was about 0. 3 lower than red soil, latosolic red soil and latosol in pK1. An extremely significant linear correlation of pK1with ZPC was observed and so was an extremely significant positive correlation of Qv （i） with organic matters.

关 键 词：表面电荷特性 可变电荷 返滴定法 Multi—Langmuir模型 

分 类 号：S152.2[农业科学—土壤学]