基于可见/近红外光谱的土壤有机质快速测定方法的研究

目的]研究在野外直接测定土壤有机质含量的方法。方法]以重铬酸钾容量法(外加热法)测定土壤样本有机质含量作为真实值,在不进行土壤样本预处理的前提下,利用近红外光谱直接扫描未作处理的土壤样本,测定土壤有机质含量,以其作为土壤有机质含量的预测值。结果]利用620和1 900 nm的波长组合,可以较好地预测土壤有机质含量,预测模型(定标模型)的相关系数为0.9,极为显著。结论]该模型对同类土壤有机质含量的预测效果很好,预测值与实测值的相关系数达到0.95。

Study on Rapid Determination of Soil Organic Matter Based on Visible and Near Infrared Spectrum

Objective] The research aimed to study the methods for direct determination of organic matter content in the fields.Method]The organic matter content of the soil samples determined by the hydroquinone volumetric method(heating method) was taken as a truth value.With the condition of no pretreatment of soil samples,near infrared spectrum was used to scan untreated soil sample directly and soil organic matter content was determined to make it as predictive value.Result]It could be good to predict the content of soil organic matter by the use of a combination of 620 and 1 900 nm.The data for prediction model(calibration model) was 0.9 and the effect was very remarkable.Conclusion] The model had good prediction effect on the content of similar soil organic matter for the correlation coefficient between the predict value and the real value reached 0.95.