The Pollen Representation of Vegetation and Climate Along an Altitudinal Gradient on the Eastern Tibetan Plateau

作者：Weihe Ren, Min Liu, Feng Qin, Quan Li, Guitian Yi, Wei‐Yu Chen, Shuming Li, Zijian Liu, Qing Peng, Chen Liang, Yan Zhao · 发表于：Land · 年份：2024 · DOI：10.3390/land13111866 · 被引用次数：5 · 研究领域：Geology and Paleoclimatology Research、Tree-ring climate responses、Ecology and Vegetation Dynamics Studies

Understanding the relationship between modern pollen assemblages and vegetation/climate for various elevations is essential for accurately interpreting fossil pollen records and conducting quantitative climate reconstructions in mountainous regions. However, these relationships for the Tibetan Plateau, which is the highest and one of the most ecologically sensitive regions globally, are still scarce. We present modern pollen assemblages from 78 topsoil samples collected along altitudinal gradients from 498 to 4046 m above sea level on the eastern Tibetan Plateau. They were distributed in alpine shrub meadows, coniferous forests, and mixed broad-leaved and coniferous forest vegetation types. Multivariate statistical methods, including discriminant analysis, indicator species analysis, logistic regression, and redundancy analysis, were employed to identify relationships among modern pollen assemblages, vegetation types, and climate along an altitudinal gradient. The results revealed that (1) vegetation types along the altitudinal gradient can be effectively differentiated by comparing pollen assemblages, discriminant analysis, and indicator species analysis; (2) the conifer/broadleaf pollen ratio (C/B) efficiently distinguished coniferous forests (C/B > 5) from mixed forests (C/B < 5); and (3) variations in modern pollen assemblages are primarily influenced by temperature, with pollen ratios, such as Artemisia/Cyperaceae (Art/Cy) and Tsuga/(Tsuga + Abies + Picea) (T/TAP),...