1. Pollen-based biome reconstruction on the Qinghai-Tibetan Plateau during the past 15,000 years.
- Author
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Li, Zhen, Wang, Yongbo, Herzschuh, Ulrike, Cao, Xianyong, Ni, Jian, and Zhao, Yan
- Subjects
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BIOMES , *FOSSIL pollen , *WESTERLIES , *POLLEN , *MOUNTAIN meadows - Abstract
Reconstruction of past vegetation change is critical for better understanding the potential impact of future global change on the fragile alpine ecosystems of the Qinghai-Tibetan Plateau (QTP). In this paper, pollen assemblages comprising 58 records from the QTP, spanning the past 15 kyrs, were collected to reconstruct biome compositions using a standard approach. Six forest biomes were identified mainly on the southeastern plateau, exhibiting a pattern of gradual expansion along the eastern margin during early to mid-Holocene times. The alpine meadow biome was separately identified based on an updated scheme, and showed notable westward expansions towards lower latitudes and higher altitudes during early Holocene times. Consistent patterns of migration could also be identified for the alpine steppe biome, which moved eastward during the late Holocene after 4 ka. As the dominant biome type, temperate steppe was distributed widely over the QTP with minor migration patterns, except for a progressive expansion to lower altitudes in the late Holocene times. The desert biome was inferred mainly as covering the northwestern plateau and the Qaidam Basin, in relatively restricted areas. The spatial distribution of the reconstructed biomes represent the large-scale vegetation gradient on the QTP. Monsoonal precipitation expressed predominant controls on the development of alpine ecosystems, while the variations in desert vegetation responded to regional moisture brought by the mid-latitude Westerlies. Temperature changes played relatively minor roles in the variations of alpine vegetation, but exerted more significant impacts on the forest biomes. • Fossil pollen based biome reconstruction on the Qinghai-Tibetan Plateau since 15 ka. • Spatial/temporal patterns of biome changes on the QTP were illustrated and examined. • Forest and alpine meadow biomes experienced migrations during the mid-Holocene. • Vegetation changes responded closely to moisture changes with spatial divergence. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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