土壤是农业生产的基础,采用近红外光谱技术实现对土壤养分的快速分析,研制分立波长型近红外土壤养分测量系统,指导农业生产过程,有助于改变现有农业生产的粗放经营状态。首先,使用FOSSXDS近红外光谱分析仪对85份东北土壤样品采集光谱,采用相关系数谱及连续投影法等化学计量学算法分析土壤的近红外光谱,并优选出总氮和有机质的特征波长;其次,基于确定的特征波长研制了一套高信噪比近红外光谱测量系统,对土壤样品的近红外光谱及测量结果进行了分析。研制的测量系统测得土壤养分中总氮和有机质的预测均方差(RMSEP)分别为0.019%和0.36%,预测相关系数(Rp)分别为0.851和0.923。通过近红外光谱分析,确定出能够代表土壤主要养分分析的特征光谱;研制的测量系统可以用于土壤养分分析,为进一步产业化应用打下基础。
Soil is the foundation of agricultural production.Rapid analysis of soil nutrients,using near infrared spectral analysis technology,can guide process of agricultural production.Developing near-infrared measuring system with discrete wavelength will change the extensive operation situation of agricultural production.First,the spectra of 85 black soil samples of northeast China,collected by FOSS XDS near-infrared spectrometer were analyzed using the correlation spectra and successive projection algorithm.Then,the characteristic wavelengths of total nitrogen and organic matter were obtained.After that the authors collected the spectra of soil samples using the measuring system with high signal to noise ratio(SNR) that the authors developed.The calibration models for total nitrogen and organic matter were established.The root mean square error of prediction(RMSEP) of total nitrogen and organic matter is 0.019% and 0.36% respectively,and the correlation coefficient of prediction(Rp) is 0.851 and 0.923,respectively.Experimental results indicate that the characteristic wavelengths for total nitrogen and organic matter can be obtained through the near infrared spectra analyses.The measuring system can be used for soil nutrient analysis and lays the foundation for the industrial applications.