目前国内用重铬酸钾容量法(180℃油浴)测定有机质。大量实验证明,此法对含各种高缩合度形态碳(为发电厂灰烬、碳、煤等)的土壤测定值偏高。为模拟试验结果,0.3g无粉煤灰土壤有机质含量为0.82%,加入10mg粉煤灰后,有机质升为2.98%,升值达3.6倍,且随粉煤灰含量的增加而升高。这表明用18℃油浴法测定值不能反映土 Currently used domestic potassium dichromate capacity method (180 ℃ oil bath) determination of organic matter. A large number of experiments show that this method contains a variety of high condensation degree of shape carbon (for power plants, ashes, carbon, coal, etc.) the measured value of the soil is high. In order to simulate the experiment results, the content of organic matter in 0.3g soil without fly ash was 0.82%. After adding 10mg fly ash, the organic matter content increased to 2.98% and increased by 3.6 times, with the content of fly ash increasing. This indicates that the value measured by the 18 ° C oil bath method does not reflect the soil