The chemical composition of wood is one of the key features that determine wood quality. The focus of this study was on identifying differences between juvenile and mature woods in Scots pine (Pinus sylvestris L.) and developing models for predicting the chemical composition of these two wood types. Chemical traits, determined by traditional wet chemistry techniques, included the proportion of lignin, polysaccharides and extractives. Partial least squares regression of Fourier transform infrared (FTIR) spectra was used for model building. The model performance was primarily evaluated by root mean squared error of predictions (RMSEP). High predictive power was attained for the content of lignin (RMSEP of 0.476 and 0.495 for juvenile and mature woods, respectively) and extractives (0.302 and 0.471), good predictive power for cellulose (0.715 and 0.696) and hemicelluloses in juvenile wood (0.719) and low predictive power for hemicelluloses in mature wood (0.823). A distinct band was observed at 1693 cm−1, and its intensity was strongly associated with the content of extractives (r = 0.968 and 0.861 in juvenile and mature woods, respectively). FTIR has proved suitable for the rapid, non-destructive, cost-efficient assessment of the chemical composition of juvenile and mature woods in Scots pine. The band at 1693 cm−1 is to be further investigated to unravel its link with individual extractive components.

中文翻译：

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使用 FTIR 光谱预测苏格兰松 (Pinus sylvestris L.) 幼年和成熟木材的化学成分

木材的化学成分是决定木材质量的关键特征之一。本研究的重点是确定苏格兰松 (Pinus sylvestris L.) 幼年和成熟木材之间的差异，并开发预测这两种木材类型化学成分的模型。由传统湿化学技术确定的化学特性包括木质素、多糖和提取物的比例。傅里叶变换红外 (FTIR) 光谱的偏最小二乘回归用于模型构建。模型性能主要通过预测的均方根误差 (RMSEP) 进行评估。对木质素（幼木和成熟木材的 RMSEP 分别为 0.476 和 0.495）和提取物（0.302 和 0.471）的含量具有高预测能力，对纤维素（0.715 和 0. 696) 和幼木中的半纤维素 (0.719) 以及成熟木中半纤维素的低预测能力 (0.823)。在 1693 cm-1 处观察到一个明显的带，其强度与提取物的含量密切相关（幼木和成熟木材中的 r 分别为 0.968 和 0.861）。FTIR 已被证明适用于对苏格兰松幼木和成熟木的化学成分进行快速、无损、经济高效的评估。将进一步研究 1693 cm-1 处的波段，以解开其与各个提取成分的联系。分别）。FTIR 已被证明适用于对苏格兰松幼木和成熟木的化学成分进行快速、无损、经济高效的评估。将进一步研究 1693 cm-1 处的波段，以解开其与各个提取成分的联系。分别）。FTIR 已被证明适用于对苏格兰松幼木和成熟木的化学成分进行快速、无损、经济高效的评估。将进一步研究 1693 cm-1 处的波段，以解开其与各个提取成分的联系。