重铬酸钾容量法中不同加热方式测定土壤有机质的比较研究

Comparison on determining the organic matter contents in the soils by different heating methods in the potassium dichromate-volumetric method

以油浴加热法[2]测定土壤有机质含量结果为基准,比较30 min或60 min 100℃恒温水浴加热法和稀释水合热法测定有机质的精确度和准确度,并获得三者的氧化校正系数平均值分别为1.16,1.13和1.33。结果表明,30 min恒温水浴加热—重铬酸钾容量分析法,可达到经典油浴加热法的测定精度和准确度,而且操作简便,是可靠的土壤有机质含量测定方法。

The precisions and accuracies of the soil organic matter contents tested by three heating methods including the boiling water bath heating 30min or 60 min and the dilution heating method were compared with the oil bath heating method as a standard conventional method. The results showed that the oxidation adjusting coefficients for above three heating method were 1.16,1.13, and 1.33, respectively. The precision and aceuryey of the boiling water bath heating method were as the same as the oil bath heating method in determining soil organic by the potassium dichromate-volumetric method. Because the boiling water bath heating 30 rain method is facility and credibility, it can be applied in measurement of soil organic matter.