First Calibration and Application of Leaf Wax n-Alkane Biomarkers in Loess-Paleosol Sequences and Modern Plants and Soils in Armenia
First Calibration and Application of Leaf Wax n-Alkane Biomarkers in Loess-Paleosol Sequences and Modern Plants and Soils in Armenia
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DOI：
10.3390/geosciences9060263
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发表时间：
2019-06
期刊：
影响因子：
2.7
通讯作者：
Yesmine Trigui;D. Wolf;L. Sahakyan;H. Hovakimyan;K. Sahakyan;R. Zech;M. Fuchs;T. Wolpert;M. Zech;D. Faust
中科院分区：
文献类型：
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作者：
Yesmine Trigui;D. Wolf;L. Sahakyan;H. Hovakimyan;K. Sahakyan;R. Zech;M. Fuchs;T. Wolpert;M. Zech;D. Faust
通过正构烷烃生物标志物分析来解释古环境条件是具有挑战性的，因为结果取决于不同的影响因素。因此，由于植物化学分类行为的不同，需要对正构烷烃模式进行区域校准。我们首次从现代植物、凋落物、表层土壤和最近在亚美尼亚(小高加索)发现的两个黄土-古土壤序列(LPS)中研究了叶蜡衍生的正构烷烃生物标志物。我们在现代样品上的结果显示，尽管植被组内植物间的变异性很大，但基于正构烷烃链长NC33(可能是NC31)的区分能力对草本植物和落叶乔木来说是有希望的。与欧洲的其他黄土记录相比，欧洲晚更新世的环境从类似苔原的(冰期)到落叶森林生境(间冰期)，我们来自两个亚美尼亚LPS的结果表明，从间冰期占主导地位的湿润草原生物群或森林草原植被过渡到更适应冰期干旱加剧的半荒漠灌木物种。
Interpreting paleoenvironmental conditions by means of n-alkane biomarker analyses is challenging because results depend on different influencing factors. Thus, regional calibration of n-alkane patterns is needed because of different plant chemo-taxonomic behavior. We investigated for the first-time leaf wax-derived n-alkane biomarkers from modern plants, litter, top soils, and two recently discovered loess-paleosol sequences (LPSs) in Armenia (Lesser Caucasus). Our results on modern samples show a promising discrimination power based on n-alkane chain length nC33 (probably nC31)) for grasses and herbs versus nC29 for deciduous trees, despite the large interplant variability within vegetation groups. In contrast with other Loess records in Europe, where Late Pleistocene environments are ranging from tundra-like (glacial) to deciduous forest habitats (interglacial), our results from two Armenian LPSs suggest a transition from humid-steppe biome or forest-steppe vegetation dominating during interglacial periods, to semi-desert shrubs species more adapted to the enhanced aridity during glacial periods.