基于近红外光谱快速分析东南极湖泊沉积物化学元素含量

RAPID ANALYSIS ON CONTENTS OF CHEMICAL ELEMENTS IN POND SEDIMENTS FROM EAST ANTARCTICA USING NEAR-INFRARED SPECTROSCOPY

以东南极罗斯岛地区的3个湖泊沉积剖面为研究对象,利用紫外-可见-近红外反射光谱仪获得了沉积物样品的光谱曲线,讨论了东南极罗斯岛湖泊沉积物的光谱特征。在沉积物化学元素分析的基础上将样品分成建模集和验证集,采用偏最小二乘法建立光谱与化学元素指标的对应关系矩阵,通过验证集预测值和测定值之间的误差参数比较,发现研究的20种元素含量均能和光谱曲线建立有效的计算关系,其中,N、C、H、Mn、Ba、P、Al、Fe、K、Se、As和Hg等元素能够达到相当精确的预测水平(预测值与测量值之间的相关系数r2>0.90)。本研究结果表明,利用近红外反射光谱快速分析东南极湖泊沉积物中元素含量是一种潜在有效的方法。

Spectra of three pond sediment profiles collected from Ross Island in East Antarctica were measured by an ultraviolet-visible-near-infrared reflectance spectrophotometer. Specific peaks and troughs were observed in the spectra,and their distribution patterns correlated well with lithology. All sediment subsamples were separated into a modeling set and a test set to establish the relationship between the spectra and the element contents using a partial least squares method. The difference between the predicted and test values showed that the contents of all 20 measured elements strongly correlated with the spectral data. Among them,the N,C,H,Mn,Ba,P,Al,Fe,K,Se,As,and Hg contents were predicted accurately（ the correlation coefficients between the predicted and tested values（ r2） were 〉0. 90）. Thus,we conclude that the element contents in sediments from East Antarctic can be determined rapidly using near-infrared reflectance spectroscopy.