Hydrological and ecosystem response to abrupt changes in the Indian monsoon during the last glacial, as recorded by sediments from Xingyun Lake, Yunnan, China

ISL OpenIR > 青海盐湖研究所知识仓储

	Hydrological and ecosystem response to abrupt changes in the Indian monsoon during the last glacial, as recorded by sediments from Xingyun Lake, Yunnan, China
	Wu, Duo 1; Zhou, Aifeng 1; Chen, Xuemei 1; Yu, Junqing 2; Zhang, Jiawu 1; Sun, Huiling 3
	2015-03-01
发表期刊	PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
卷号	421 页码:15-23
关键词	Lake Level Indian Summer Monsoon Abrupt Change Ecosystem Last Glacial Xingyun Lake
摘要	The Indian Summer Monsoon (ISM) is the major moisture source of precipitation in southwest China and plays an important role in regional environmental change and in economic and social development, since abrupt changes of the ISM can cause crop failures and flooding that impact the livelihood of a large population. However, with the exception of speleothem records, abrupt changes of the ISM during the last glacial are not well documented in terrestrial records. Here we present a sediment record from Xingyun Lake in Yunnan Province, southwest China, spanning the interval 36.4 ka BP to 13.4 ka BP (1 ka = 1000 cal a) which documents the occurrence of a series of millennial-scale episodes which may reflect the abrupt weakening of the ISM. Seven AMS C-14 dates from terrestrial wood fragments provide a robust chronology. The results demonstrate that increases in the coarse sediment fraction (>30 mu m) correspond to increases in the concentration of Pediastrum, the grain size of magnetic minerals, carbonate content and C/N ratios, which together indicate episodes of low lake level. In addition, pollen analysis indicates that Quercus (oak) increased and that ferns decreased during intervals of abrupt weakening of the ISM, indicating a drier environment. Nine abrupt shifts to a low lake level are documented for the studied interval and three of them are correlative with Heinrich events 1 to 3. Our study supports the hypothesis that, in response to the cold events in the North Atlantic associated with massive iceberg influxes and the corresponding slowing down of Atlantic meridional overturning circulation, the mean latitudinal extent of the ITCZ shifted southwards. As a result of an atmospheric teleconnection there was a corresponding decrease in precipitation associated with ISM precipitation, which caused reduced fluvial runoff in Yunnan. (C) 2015 Elsevier B.V. All rights reserved.
语种	英语
引用统计
文献类型	期刊论文
条目标识符	http://ir.isl.ac.cn/handle/363002/5741
专题	青海盐湖研究所知识仓储中国科学院青海盐湖研究所
作者单位	1.Lanzhou Univ, Collaborat Innovat Ctr Arid Environm & Climat Cha, MOE Key Lab Western Chinas Environm Syst, Lanzhou 73000, Peoples R China 2.Chinese Acad Sci, Qinghai Inst Salt Lakes, Xining 810008, Peoples R China 3.Yunnan Normal Univ, Coll Tourism & Geog Sci, Kunming 650500, Peoples R China
推荐引用方式 GB/T 7714	Wu, Duo,Zhou, Aifeng,Chen, Xuemei,et al. Hydrological and ecosystem response to abrupt changes in the Indian monsoon during the last glacial, as recorded by sediments from Xingyun Lake, Yunnan, China[J]. PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY,2015,421:15-23.
APA	Wu, Duo,Zhou, Aifeng,Chen, Xuemei,Yu, Junqing,Zhang, Jiawu,&Sun, Huiling.(2015).Hydrological and ecosystem response to abrupt changes in the Indian monsoon during the last glacial, as recorded by sediments from Xingyun Lake, Yunnan, China.PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY,421,15-23.
MLA	Wu, Duo,et al."Hydrological and ecosystem response to abrupt changes in the Indian monsoon during the last glacial, as recorded by sediments from Xingyun Lake, Yunnan, China".PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY 421(2015):15-23.