电位滴定法研究可变电荷土壤表面酸碱性质的进展  

Research Progress on the Acid-base Properties of Variable Charge Soils Using Potentiometric Titration

作　　者：温晓翠 李九玉[3] 宋洁 陶亮 WEN Xiaocui;LI Jiuyu;SONG Jie;TAO Liang(National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China,Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management,Institute of Eco-environmental and Soil Sciences,Guangdong Academy of Sciences,Guangzhou 510650,China;School of Environmental Science and Engineering,Guangdong University of Technology,Guangzhou 510006,China;Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;School of Environment,Jinan University,Guangzhou 510632,China)

机构地区：[1]广东省科学院生态环境与土壤研究所,华南土壤污染控制与修复国家地方联合工程研究中心,广东省农业环境综合治理重点实验室,广州510650 [2]广东工业大学环境科学与工程学院,广州510006 [3]中国科学院南京土壤研究所,南京210008 [4]暨南大学环境学院,广州510632

出　　处：《土壤学报》2022年第4期910-923,共14页Acta Pedologica Sinica

基　　金：国家自然科学基金项目(42077016,41877038);广东省“珠江人才计划”本土创新科研团队项目(2017BT01Z176)资助。

摘　　要：我国长江以南地区的土壤富含铁铝氧化物,其土壤胶体表面电荷具有可变性,显著不同于温带地区的恒电荷土壤,因而称之为可变电荷土壤。开展可变电荷土壤的表面特性研究对农业可持续发展、土壤资源保护等均具有重要的现实意义。电位滴定法是开展可变电荷土壤表面特性研究最直接有效的方法。本文首先总结了电位滴定法的实验条件设置对可变电荷土壤表观电荷零点的影响,在此基础上,归纳了应用电位滴定法结合表面络合模型开展可变电荷土壤酸碱特性的研究进展,分类讨论了黏土矿物组成、氧化物、有机质等相关影响因子对可变电荷土壤酸碱缓冲能力的影响,并展望可变电荷土壤表面酸碱缓冲能力的未来研究。本文将有助于初学者理解可变电荷土壤,呼吁更多学者关注可变电荷土壤的酸碱缓冲特性研究及其在土壤资源可持续利用中所起的重要作用。Compared with the constant charge soils that distribute in temperate regions,the variable charge soils in tropical and subtropical zones are unique soils,with highly variable particle surface charges.Investigations on the surface chemical characteristics of variable charge soils have received considerable attentions.The potentiometric acid-base titration method is the most straightforward approach to qualitatively and quantitatively identify the surface chemical characteristics of variable charge soils.In this paper,the characteristics of variable charge soils are briefly described and the concept and difference of point of zero charge(PZC)is described and classified according to(i)the conditions for surface charge measurement,(ii)the modes of expression for PZC,and(iii)measurement methods for surface charge of soil colloidal particles.On this basis,the influence of the acid-base potentiometric titration setup conditions on the observed PZC,including co-existing ions,ionic strength of the solution,pre-equilibrium time,titration ranges,reaction atmosphere and titration method,is summarized and discussed.Furthermore,the research progresses on the application of potentiometric titration combined with surface complexation model(SCM,including diffuse layer model,basic stern model,triple layer model and distribution multi-site complexity and so on)to analyze the acid-base buffering capacity of variable charge soils were further summarized.Moreover,how related factors such as clay mineral composition,metal oxides,organic matter and other factors,affect the acid-base buffering capacity of variable charge soils are discussed.We believe that future studies on the variable charge soils could be carried out with the hope to:(1)establish a typical acid-base potentiometric titration method for all types of soils;and(2)verify if the combination of various surface complexation models could accurately quantify the acid-base buffer capacity of variable charge soils.It is hoped that this review can help soil science beginners to un

关 键 词：可变电荷土壤 电荷零点 电位滴定 表面络合模型 土壤资源 

分 类 号：X53[环境科学与工程—环境工程]