Novel estimation of the humification degree of soil organic matter by laser-induced breakdown spectroscopy
Novel estimation of the humification degree of soil organic matter by laser-induced breakdown spectroscopy
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DOI：
10.1016/j.sab.2014.06.016
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发表时间：
2014-09-01
影响因子：
3.3
通讯作者：
Bastos Pereira Milori, Debora Marcondes
中科院分区：
文献类型：
--
作者：
Ferreira, Edilene Cristina;Ferreira, Ednaldo Jose;Bastos Pereira Milori, Debora Marcondes
土壤有机质(SOM)是陆地碳的重要储存库，可作为大气碳储存的替代品，有助于减缓全球变暖。土壤管理有利于大气碳的吸收或从土壤有机质释放到大气中。因此，腐殖化程度(HD)是土壤有机质顽固性的一个指标，它可以提供对不同管理方式下土壤固碳能力的估计。可以使用包括荧光光谱在内的各种分析技术来估计SOM的HD。在本工作中，首次评估了激光诱导击穿光谱(LIBS)估计SUM的HD的可能性。利用激光诱导荧光光谱(LIFS)测定的荧光发射光谱中Al、Mg和Ca的发射线强度，建立了基于k近邻(k-NN)方法的多元校正模型。该模型(A-LIBS)的预测值与LIFS结果具有很强的相关性，皮尔逊系数为0.87。用样品中的总碳对A-Libs进行归一化后得到的SUM的HD与LIFS的结果(0.94)有很强的相关性，这表明LiBS在这一新的应用中具有很大的潜力。(C)2014爱思唯尔B.V.保留所有权利。
Soil organic matter (SOM) constitutes an important reservoir of terrestrial carbon and can be considered an alternative for atmospheric carbon storage, contributing to global warming mitigation. Soil management can favor atmospheric carbon incorporation into SUM or its release from SOM to atmosphere. Thus, the evaluation of the humification degree (HD), which is an indication of the recalcitrance of SOM, can provide an estimation of the capacity of carbon sequestration by soils under various managements. The HD of SOM can be estimated by using various analytical techniques including fluorescence spectroscopy. In the present work, the potential of laser-induced breakdown spectroscopy (LIBS) to estimate the HD of SUM was evaluated for the first time. Intensities of emission lines of Al, Mg and Ca from LIBS spectra showing correlation with fluorescence emissions determined by laser-induced fluorescence spectroscopy (LIFS) reference technique were used to obtain a multivaried calibration model based on the k-nearest neighbor (k-NN) method. The values predicted by the proposed model (A-LIBS) showed strong correlation with LIFS results with a Pearson's coefficient of 0.87. The HD of SUM obtained after normalizing A-LIBS by total carbon in the sample showed a strong correlation to that determined by LIFS (0.94), thus suggesting the great potential of LIBS for this novel application. (C) 2014 Elsevier B.V. All rights reserved.