近红外光谱法快速分析有机肥料中有机质、总养分和pH值

建立了近红外光谱法结合偏最小二乘(PLS)法测定126种有机肥料中有机质、总养分和p H值的快速方法。采用K–S法分类,选取S–G平滑、S–G导数、多元散射校正和均值平均化4种前处理方法对粉碎后样品的近红外光谱信息进行预处理,以PLS法建立定量分析模型。结果表明,有机肥料中总养分的RC,SEC,RP,SEP,RPD分别为0.990,1.272%,0.985,1.084%,5.9;p H值的RC,SEC,RP,SEP,RPD分别为0.910,0.344%,0.737,0.428%,2.9。有机质项目根据国标方法分为小于40%、小于55%和大于55%3种样品进行分析,3种样品的RP分别为1.000,0.989,1.000;RPD分别为18.9,17.5,8.8。对比国标方法,有机质和总养分的测定精度满足实验室精确分析要求,p H值测定法可用于定量分析。NIR–PLS法实现了对有机肥料进行无损快速的检测分析。

Rapid Analysis of Organic Matter,Total Nutrient and pH of Organic Fertilizer by Near-infrared Relfectance Spectroscopy

A new method was explored to predict the content of organic matter, total nutrient and pH value of organic fertilizer using near-infrared spectroscopy(NIR) combined with partial least squares(PLS). The near-infrared spectroscopy of 126 pulverized samples were pretreated by S–G smooth, S–G derivative, multiplicative scatter correction(MSC) and average, and the models were established by PLS using K–S classification. The results showed that RC, SEC, RP, SEP and RPD of total nutrient were 0.990, 1.272%, 0.985, 1.084%, 5.9; and RC, SEC, RP, SEP and RPD of pH value were 0.910, 0.344%, 0.737, 0.428%, 2.9, respectively. The organic matter was divided into three samples according to national standard(<40%, <55% and >55%), RP were 1.000, 0.989, 1.000; and RPD were 18.9, 17.5, 8.8, respectively. The determination accuracy of organic matter and total nutrient could be used in accurate analysis, and pH value test could be used in quantitative analysis. NIR–PLS method could be used in quantitative analysis of main components of organic fertilizer rapidly and nondestructive.