土壤有机质测定方法对比分析  

Comparative tests on different methods for content of soil organic matter

作　　者：钱宝[1] 刘凌[1] 肖潇[2] 

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [2]长沙理工大学水利工程学院,湖南长沙410114

出　　处：《河海大学学报（自然科学版）》2011年第1期34-38,共5页Journal of Hohai University(Natural Sciences)

基　　金：国家自然科学基金(50879018)

摘　　要：采用不同方法(TOC分析仪法、550℃烧失量法、950℃烧失量法和水合热重铬酸钾氧化比色法)测定长江底沉积物标准物质中有机质含量,并分析不同测定方法的准确度、精密度及对测定土壤有机质含量的影响,结果表明:在实验准确度和精密度方面,TOC分析仪法最高,950℃烧失量法最低.采用以上4种方法对南京秦淮河沿程5个断面采取的表层底泥沉积物样品进行对比分析,结果表明:实验室测定土壤有机质含量推荐采用TOC分析仪法,其次为550℃烧失量法;水合热重铬酸钾氧化比色法测定结果偏低,而950℃烧失量法测得的结果偏差较大,不能代表样品的有机质含量,故不宜采用.Four kinds of methods,TOC analyzer,550℃ loss-on-ignition（LOI）,950℃ LOI and hydrated heat potassium dichromate oxidation-colorimetry,were employed to determine the content of organic matter（OM） of the sediments in Changjiang River.The accuracy and precision of the above methods as well as their influences on the measurements of content of soil OM were discussed.Standard OM reference materials and five sediment samples from Qinhuai River in Nanjing were analyzed.The results of the four methods were compared.A conclusion is drawn that the test accuracy of the four methods has the sequence of TOC analyzer,550°C LOI method,hydrated heat potassium dichromate oxidation-colorimetry and 950°C LOI method.The precision has the sequence of TOC analyzer,hydrated heat potassium dichromate oxidation-colorimetry,550°C LOI method and 950°C LOI method.The TOC analyzer method and the 550°C LOI method are superior,and the other two should not be employed.The results of the hydrated heat potassium dichromate oxidation-colorimetry are too small and the 950°C LOI method leads to large errors in the results.

关 键 词：土壤有机质 烧失量 TOC分析仪法 烧失量法 水合热重铬酸钾氧化比色法 

分 类 号：X502[环境科学与工程—环境工程] S151.93[农业科学—土壤学]