不同消解方法测定土壤有机质含量

重铬酸钾为氧化剂，选用油浴、磷酸浴、电沙浴、微波消解加热消解土壤有机质，比较有机质测得量。结果表明：微波法有机碳氧化率最高，精密度和准确度最高，平行测定RSD为0．42％～0．69％。磷酸浴法氧化率高，准确度与精密度高，平行测定RSD为0．43％～0．70％。磷酸浴法温度稳定，易于控制，简单，安全，环保。微波法和磷酸浴法试验结果相对误差为＋0．61％～＋1．39％，可以作为实验室分析土壤有机质的标准加热消解方法。油浴法与沙浴法氧化率较低，试验误差大。油浴法温度不易控制，存在环境污染。

Determination of soil organic matter under different digestion methods

K2Cr207 as the oxidizer, select oil bath, H3PO4 bath, sand bath and microwave heating methods to heat soil, compare the testing values of soil organic matter. The results showed：microwave heating method has the highest oxidation ratio,the highest precision and accuracy, the variation of RSD is 0.42% -0.69%. H3PO4 bath method has high oxidation ratio, high precision and accuracy, the variation of RSD is 0.43% - 0.70%. The heating temperature is stable, easy to control, it is simple, safe and environment protective. The relative error of HaPO4 bath and microwave heating methods is ＋0.61% - ＋ 1.39% ,the two methods can be selected as the standard decomposing methods in soil organic matter determination. Oil bath and sand bath methods have comparatively low oxidation ratio,more experimental errors. The boiling temperature is difficult to control in oil bath method and it causes environment pollution