TY  - JOUR
A1  - Wang, Yongbo
A1  - Liu, Xingqi
A1  - Herzschuh, Ulrike
A1  - Yang, Xiangdong
A1  - Birks, H. John B.
A1  - Zhang, Enlou
A1  - Tong, Guobang
T1  - Temporally changing drivers for late-Holocene vegetation changes on the northern Tibetan Plateau
JF  - Palaeogeography, palaeoclimatology, palaeoecology : an international journal for the geo-sciences
N2  - Fossil pollen records have been widely used as indicators of past changes in vegetation and variations in climate. The driving mechanisms behind these vegetation changes have, however, remained unclear. In order to evaluate vegetation changes that have occurred in the northern part of the Tibetan Plateau and the possible drivers behind these changes, we have applied a moving-window Redundancy Analysis (RDA) to high resolution (10-15 years) pollen and sedimentary data from Lake Kusai covering the last 3770 years. Our analyses reveal frequent fluctuations in the relative abundances of alpine steppe and alpine desert components. The sedimentary proxies (including total organic carbon content, total inorganic carbon content, and "end-member" indices from grain-size analyses) that explain statistically some of the changes in the pollen assemblage vary significantly with time, most probably reflecting multiple underlying driving processes. Climate appears to have had an important influence on vegetation changes when conditions were relatively wet and stable. However, a gradual decrease in vegetation cover was identified after 1500 cal a BP, after which the vegetation appears to have been affected more by extreme events such as dust-storms or fluvial erosion than by general climatic trends. Furthermore, pollen spectra over the last 600 years are shown by Procrustes analysis to be statistically different from those recovered from older samples, which we attribute to increased human impact that resulted in unprecedented changes to the vegetation composition. Overall, changes in vegetation and climate on the northern part of the Tibetan Plateau appear to have roughly followed the evolution of the Asian Summer Monsoon. After taking into account the highly significant millennial (1512 years) periodicity revealed by time-series analysis, the regional vegetation and climate changes also show variations that appear to match variations in the mid-latitude westerlies.
KW  - Asian Summer Monsoon
KW  - Late-Holocene
KW  - Pollen
KW  - Procrustes analysis
KW  - Redundancy analysis
KW  - Tibetan Plateau
KW  - Vegetation
KW  - Westerlies
Y1  - 2012
U6  - https://doi.org/10.1016/j.palaeo.2012.06.022
SN  - 0031-0182
VL  - 353
IS  - 8
SP  - 10
EP  - 20
PB  - Elsevier
CY  - Amsterdam
ER  -