以我国东北黑土为研究对象，分析了2004—2005年采集的136个土壤样品在3699～12000 cm-1范围的近红外光谱，利用偏最小二乘法建立了原始光谱吸光度与土壤有机碳、全氮和碳氮比之间的定量分析模型.结果表明：土壤有机碳和全氮的模型拟合效果良好，决定系数R2分别为0.92和0.91（P<0.001），相对分析误差RPD分别为3.45和3.36，利用该模型对验证样本土壤有机碳和全氮的预测值与实测值之间的相关系数分别为0.94和0.93（P<0.001），表明可以用近红外光谱分析法对黑土有机碳和全氮含量进行测定.但是利用近红外光谱分析法对土壤碳氮比的预测并不理想，虽然验证样本集黑土碳氮比模型预测值与实测值呈显著相关（r＝0.74,P<0.001）,但是校正模型的R2为0.61，RPD仅为1.61，建立的模型不能对黑土碳氮比做出合理的估测.
In this study, near infrared reflectance spectroscopy (NIRS) was used to determine the organic carbon (OC), total nitrogen (TN), and C/N ratio in black soil of Northeast China. Based on the 3699-12000 cm-1 NIRS of 136 black soil samples collected in 2004-2005, and by using. partial least square (PLS), the related quantitative models were established. Leave one out cross validation showed that the OC and TN were well predicted, with the values of coefficient of determination (R2) being 0.92 and 0.91, RPD (the ratio of standard deviation of validation set to root mean square error of cross validation) being 3.45 and 3.36, and correlation coefficient (r) being 0.94 and 0.93 respectively, suggesting that NIRS had the potential to predict the OC and TN in black soil of Northeastern China. However, the C/N ratio was poorly predicted, with R2=0.61, RPD=1.61, and r=0.74, indicating that NIRS could not give reasonable prediction for the C/N ratio in black soil.