Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy is a powerful tool for investigating the biochemical fingerprint of plants, but its applicability to tundra plant leaves has yet to be addressed. The present study aimed to apply ATR-FTIR measurement to characterize tundra plant leaves and to discriminate these among plant species with different growth forms. The ATR-FTIR spectra in the fingerprint region (1800–800 cm⁻¹) of live and dead leaves from 14 tundra plant species of shrubs, forbs, graminoids, and mosses showed a variability in overall appearance among plant species and a degree of similarity between live and dead leaves of the same plant species. Four highest peaks were found at 1637–1575 cm⁻¹, 1452–1406 cm⁻¹, 1325–1313 cm⁻¹, and 1058–1022 cm⁻¹ in these spectra and are attributed to chemical features of lignin, cellulose, and/or oxalate. Principal component analyses showed that leaves of Oxyria digyna and other forbs had distinctive spectral characteristics attributable to the content of oxalate and other putative compounds and that contents of lignin relative to cellulose were generally greater in shrubs than in graminoids and mosses. These results demonstrated that ATR-FTIR spectroscopy is useful for future applications in polar biology and ecology, for example the description of functional traits of arctic plants and decomposition processes by microbes.

衰减全反射傅里叶变换红外（ATR-FTIR）光谱是研究植物生化指纹的有力工具，但其对苔原植物叶子的适用性尚未得到解决。本研究旨在应用 ATR-FTIR 测量来表征苔原植物叶子，并区分不同生长形式的植物物种。灌木、禾本科植物、禾本科植物和苔藓等 14 种苔原植物的活叶和死叶的指纹区域 (1800–800 cm ⁻¹ ) 的 ATR-FTIR 光谱显示植物物种之间整体外观的差异以及同一植物物种的活叶和死叶之间的相似程度。发现四个最高峰，分别为 1637–1575 cm ⁻¹ 、1452–1406 cm ⁻¹ 、1325–1313 cm ⁻¹ 和 1058–1022 cm ⁻¹ 在这些光谱中，归因于木质素、纤维素和/或草酸盐的化学特征。主成分分析表明，Oxyria digyna 和其他草本植物的叶子由于草酸盐和其他假定化合物的含量而具有独特的光谱特征，并且灌木中木质素相对于纤维素的含量通常高于禾本科植物和苔藓。这些结果表明，ATR-FTIR 光谱对于极地生物学和生态学的未来应用非常有用，例如描述北极植物的功能特征和微生物的分解过程。