摘要
采用近红外漫反射光谱和偏最小二乘法（PLS）建立了土壤锌快速分析的定量模型，并进行了波段优选。首先，基于单波长模型预测效果将全体样品划分为定标集和预测集；然后，采用多元散射校正（MSC）和Savitzky-Golay（SG）平滑方法对光谱进行预处理。选取全谱400～2500nm，400～1100nm，1100～1900nm，1900～2500nm，580～900nm等5个波段，每个波段分别采用原谱、一阶导数谱、二阶导数谱，共建立了15个定标模型。同时调整SG平滑点数和PLS因子数，每个模型分别进行PLS数值实验，按照预测效果进行优选。结果显示，采用1900-2500nm波段一阶导数谱的模型效果最好，预测相关系数（RP）、RMSEP、RRMSEP分别为0．806，31．0mg／kg和19．96％。这些结果表明，1900-2500nm波段可以代替全谱波段得到更好的预测效果，可为设计专用土壤近红外光谱仪提供依据。
The quantification model of zinc rapid analysis in the soils was established by using near-infrared diffuse reflectance spectroscopy and a Partial Least Square （PLS） method, and the optimal measured wave band was also selected. All the samples were divided into calibration set and prediction set based on the prediction effect of single wavelength model, and then the spectra were pretreated by Multiplicative Scatter Correction （MSC） and Savitzky-Golay （SG） smoothing methods. The following five wave bands, the whole region 400-2 500 nm,400-1 100 nm,1 100-1 900 nm,1 900-2 500 nm,580-900 nm were selected, and 15 calibration models were constructed for each band selected by the original spectra, the first derivative spectra and the second derivative spectra respectively. By simultaneous adjusting the numbers of SG smoothing points and PLS factors, the PLS computational experiments for each model were carried out and the best model was selected according to the prediction effect. The results indicate that the prediction effect of the model using the first derivative spectra in 1 900-2 500 nm is the best, and its prediction correlation coefficient （RP）, RMSEP and RRMSEP are 0.806, 31.0 mg/kg, and 19.96% respectively. Obtained results show that 1 900-2 500 nm can replace the whole band to get a better calibration effect, and can provide a basis for the design of special soil near-infrared spectroscopy instruments.
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2010年第3期586-592,共7页
Optics and Precision Engineering
基金
国家自然科学基金资助项目(No.10771087)
广东省自然科学基金资助项目(No.7005948)
广东省科技计划资助项目(No.2007A020905001
2007B030501008
2007B020714001)
广州市科技攻关项目(No.2007Z3-E0281)
关键词
土壤
锌
近红外漫反射光谱
偏最小二乘法
波段选择
soil
Zn
near-infrared diffuse reflectance spectroscopy
partial least square method
waveband choice
