基于近红外光谱法的沉积物间隙水化学组分快速测量

Rapid Determination of Chemical Components in Interstitial Water of Lake Sediments Using Near-Infrared Spectroscopy

通过对巢湖柱状沉积物剖面间隙水样品的近红外光谱(NIR)分析,采用OSC+WC和WC+OSC光谱预处理方法,结合偏最小二乘法(PLS)回归,建立了分层沉积物间隙水中TN,NH3-N,PO33-,TOC和SiO3-的校正模型,该模型的TN,NH3-N,PO33-,TOC和SiO3-的预测值与实测值的校正相关系数分别为0.975,0.989,0.937,0.862和0.888,校正标准误差分别为0.353,0.238,0.0313,2.005和2.674mg·L-1,预测相关系数分别为0.912,0.918,0.773,0.337和0.856,预测标准误差分别为1.424,0.945,0.081,7.866和4.273mg·L-1。实验结果表明,近红外光谱技术有潜力作为快速测定湖泊沉积物间隙水样品中主要化学指标的新方法。

The near infrared reflectance spectra（NIRS） of interstitial water samples of lake sediments in Chaohu lake were determined by near-infrared reflectance spectrometry.The respective near NIRS calibration models for predicting total nitrogen（TN）,total organic carbon（TOC）,phosphorus（PO3-3）,ammonia nitrogen（NH3-N） and silicate（SiO-3） were built using partial least squares（PLS） algorithm with two spectral pretreatment tools including,wavelet compression combining orthogonal signal correction（OSC） and orthogonal signal correction（OSC） combining wavelet compression.The correlation coefficients between measured values and predicted values in calibration set for TN,NH3-N,PO3-3,TOC and SiO-3 were 0.975,0.989,0.937,0.862 and 0.888,respectively.RMSEC（root mean square error of the calibration）for TN,NH3-N,PO3-3,TOC and SiO-3 were 0.353,0.238,0.031 3,2.005 and 2.674 mg·L-1,respectively.The correlation coefficients between measured values and predicted values in validation set for TN,NH3-N,PO3-3,TOC and SiO-3 were 0.912,0.918,0.773,0.337 and 0.856,respectively.RMSEP（root mean square error of the prediction）for TN,NH3-N,PO3-3,TOC and SiO-3 were 1.424,0.945,0.081,7.866 and 4.273 mg·L-1,respectively.