Tibetan Dust Accumulation Linked to Ecological and Landscape Response to Global Climate Change

Authors

Xianmei Huang, Shantou University and Purdue University
Xiaodong Miao, Linyi UniversityFollow
Qiufang Chang, Zhengzhou Normal University
Jiemei Zhong, Shantou University
Joseph A. Mason, University of Wisconsin-MadisonFollow
Paul R. Hanson, University of Nebraska-LincolnFollow
Xianjiao Ou, Jiaying University
Liubing Xu, South China Normal University
Zhongping Lai, Shantou University and China University of GeosciencesFollow

ORCID IDs

Xianmei Huang

Xiaodong Miao

Joseph Mason

Paul Hanson

Liubing Xu

Zhongping Lai

Date of this Version

1-16-2022

Citation

Geophysical Research Letters 49:1 (16 January 2022), e2021GL096615 (10 pp.)

doi: 10.1029/2021GL096615

Comments

Copyright © Xianmei Huang, Xiaodong Miao, Qiufang Chang, Jiemei Zhong, Joseph A. Mason, Paul R. Hanson, Xianjiao Ou, Liubing Xu, and Zhongping Lai. Published by Wiley Open Access. This work is licensed under a Creative Commons Attribution 4.0 International License.

Abstract

The Tibetan Plateau (TP) is a hotspot of earth system research, and understanding its landscape and ecosystem evolution has been hampered by the lack of time-constrained geological records. Geochronological data from 14 loess sites covering a large region in the Tibetan interior show that the TP loess, rather than accumulating during glacial periods, began aggrading at either 13.4 ± 0.4 or 9.9 ± 0.2 ka. An ecological threshold was crossed, when warmer and wetter conditions resulted in increased vegetation cover enabling dust trapping. This dust accumulation model is out of phase with that of the Chinese Loess Plateau (CLP) where high sedimentation rates occurred during the cold/dry glacial stages. The TP loess accumulation is in response to global climate change, at both orbital (glacial/interglacial) and millennial (e.g., Younger Dryas event) time scales, despite more complexity via ecological and landscape processes than the CLP loess.

It is very important to understand the processes of landscape and ecosystem evolution in Tibet to adapt to and mitigate the consequences from potential abrupt future climate changes, but not enough well-dated geological records are available. In this study, we present stratigraphic and numerical age results from 14 loess sites covering a large region in the Tibetan interior. Results show that Tibetan loess began aggrading at either 13.4 ± 0.4 or 9.9 ± 0.2 thousand years ago. Tibetan loess accumulated during warm/interglacial conditions of the Holocene and not during the last glacial period when loess aggradation rates in the Chinese Loess Plateau were high. In Tibet, vegetation cover, which was lowered during the last glacial period, increased during Holocene warming allowing for loess accumulation.