土壤碳酸盐间接测定方法研究及其应用  

An Indirect Method for Determination of Soil Total Carbonate

作　　者：彭洪翠[1] 肖和艾[1] 吴金水[1] 苏以荣[1] 李新爱[1] 唐国勇[1] 

机构地区：[1]中国科学院亚热带农业生态研究所亚热带农业生态重点实验室

出　　处：《土壤》2006年第4期477-482,共6页Soils

基　　金：中国科学院知识创新工程项目(KZCX3–SW–426);国家自然科学基金重点项目(40235057);国家重点基础研究发展规划项目(G1999011802;2002CB412503)共同资助。

摘　　要：通过添加CaCO3内标法及与中和滴定法进行比较,提出了采用C/N分析仪测定的土壤总C量与重铬酸钾氧化法测定的有机C量差值估算土壤碳酸盐含量的方法。采用该方法对广西环江县喀斯特低山区石灰岩发育的土壤和湖南沅江平原湖区湖积物形成的土壤的碳酸盐含量进行了分析。结果表明,石灰岩发育的土壤,林地、旱地和稻田含碳酸盐的土样占总土样数的比例依次为50.0%、43.7%和2.1%,其土壤碳酸盐平均含量分别为134、15.7和37.1g/kg。湖积物形成的土壤,新垦旱地、熟化旱地和稻田土样100%含碳酸盐,其土壤碳酸盐平均含量分别为73.3、46.6和37.7g/kg。成土母质和土地利用方式对土壤碳酸盐含量有明显的影响。A new indirect method for determination of soil carbonate was proposed and established by comparing with neutralization titration method in measuring the recovery of added CaCO3. First, soil total carbon content （TC） was measured with the elemental analyzer （Vario MAX C/N）, and then soil organic carbon content （SOC） with the potassium dichromate oxygenation method. And finally, based on difference between TC and SOC, soil carbonate content （SIC） was estimated. Using the indirect method, total carbonate in calcareous soil and lacustrine sediment soil from Guangxi and Hunan in subtropical China was determinated. Results indicated that only some of the calcareous soil samples contain carbonates. The proportion of soil samples which contain carbonate in woodland, upland, and paddy soil was 50.0%, 43.7% and 2.1%, respectively. The carbonate contents of these woodland, upland and paddy soil were 134, 15.7 and 37.1 g/kg, respectively. All of the lacustrine sediment soil samples contained carbonate with average carbonate contents of 73.3, 46.6 and 37.3 g/kg, respectively in upland cultivated for three to five years, upland cultivated for a long time and paddy soil. The impact of land use and soil parent on the soil carbonates content is significant.

关 键 词：土壤碳酸盐 测定方法 石灰性土壤 湖积物形成土壤 

分 类 号：S153[农业科学—土壤学]