燃烧-红外吸收光谱法是土壤和沉积物中总碳含量测定的标准方法,为探究元素分析仪发展为土壤、沉积物中总碳含量标准方法的可行性,进行了题示项目研究。选取5种具有代表性的土壤、沉积物标准物质,分别采用燃烧-红外吸收光谱法和元素分析仪进行测定。结果表明:燃烧-红外吸收光谱法测定值的相对标准偏差(RSD,n=6)为1.2%~2.7%,相对误差为-2.9%~0.63%;元素分析仪测定值的RSD(n=6)为0.24%~2.7%,相对误差为-3.3%~0.84%;两种方法t检验结果均满足｜t｜<t_0.05,P>0.05,表明两种方法无显著性差异。基于元素分析仪简便、快速、适用于大批量样品测定及具有较高的准确度和精密度,因此可考虑将其发展为土壤和沉积物等地质样品中总碳含量测定的标准方法。

Combustion-infrared absorption spectrometry is a standard method for the determination of total carbon in soil and sediment. In order to explore the feasibility of developing the elemental analyzer into a standard method for the determination of total carbon in soil and sediment, the research mentioned by this article was carried out. Five representative soil and sediment reference materials were selected and determined by combustion-infrared absorption spectrometry and elemental analyzer. It was shown that RSDs (n=6) of the determined values obtained by combustion-infrared absorption spectrometry were in the range of 1.2%-2.7%, with relative errors ranged from -2.9% to 0.63%, and RSDs (n=6) of the determined values obtained by elemental analyzer were in the range of 0.24%-2.7%, with relative errors ranged from -3.3% to 0.84%. The results of t test for the two methods were satisfied ｜t｜<t_(0.05) and P>0.05, indicating that there was no significant difference between the two methods. Based on these facts that the elemental analyzer was simple, rapid, and suitable for the determination of large quantities of samples, which had high accuracy and precision, so it could be considered as a standard method for the determination of total carbon in geological samples such as soil and sediment.