摘要： 为了便捷、安全、准确地测定土壤有机质含量，采用河北省不同有机质含量的土壤样品和国标土壤样品为试验材料，以油浴加热重铬酸钾容量法（NY/T1121.6-2006，即油浴加热法）为标准方法，对其中的油浴加热条件进行了改进即烘箱加热法。同时对烘箱恒温180℃测定土壤有机质的保温时间、加热器皿进行了研究。结果表明，烘箱加热法测定土壤有机质的标准差为0.04~0.11 g/kg，变异系数为0.32%~0.55%；而油浴加热法测定土壤有机质的标准差为0.06~0.25 g/kg，变异系数为0.77%~1.46%。烘箱加热法测定的土壤有机质含量（Y）与油浴加热法测定的土壤有机质含量（X）呈极显著相关，回归方程Y=0.990 X+0.154（r=0.999 > r_0.01=0.874）。统计检验显示，2种方法测定土壤有机质含量没有明显差异，t（0.385）< t_0.01（3.707），即2种测定方法有着同样的准确度；而2种测定方法的变异系数则存在显著差异，t（5.979）> t_0.01（3.707），显然烘箱加热法测定土壤有机质的精密度明显高于油浴加热法。与标准方法即油浴加热法相比，烘箱恒温180℃用150 mL三角瓶保温氧化30 min测定土壤有机质准确度高、重现性好，而且高效、安全、环保、实用。

关键词: 烘箱加热法, 土壤有机质, 重铬酸钾容量法

Abstract: In order to determine the soil organic matter content conveniently,safely and precisely,the soil samples of different organic matter content in Hebei Province and national standard soil sample were used as experimental materials.The oil bath heating method(NY/T1121.6-2006) was regarded as a standard method.That was the Potassium dichromate volumetric method by the oil bath heating.The feasibility was studied by the oven heating instead of the oil bath heating.At the same time the heating time and heating containers were studied by the oven heating oxidation of 180℃.The results showed that the standard deviation and coefficient of variation were 0.04-0.11 g/kg,0.32%-0.55% by the oven heating method,and 0.06-0.25 g/kg,0.77%-1.46% by the oil bath heating method.The soil organic matter contents between oven heating method and oil bath heating method had extremely significant correlation.The regression equation was Y=0.990 X +0.154(r=0.999 > r_0.01=0.874).Statistics test showed that there was no significant difference in soil organic matter content between two methods.However,there were significant differences in variation coefficients.The oven heating 30 min/180℃ of 150 mL triangle bottle had the same accuracy and the higher precision compared with the standard method.And the oven heating method was high efficiency,safety,environmental protection and utility.

Key words: Oven heating method, Soil organic matter, Potassium dichromate volumetric method

中图分类号: 

• S158