Changes in climate and vegetation of central Guizhou in southwest China since the last glacial reflected by stalagmite records from Yelang Cave----Institute of Geochemistry Chinese Academy of Sciences

Two stalagmites (6-cm and 18-cm long) from Yelang Cave (26 2'28"N, 105 44'11"E) in central Guizhou of China have been dated by ICP-MS Th-230/U, Pb-210 and AMS C-14 dating methods. Low U but high Th contents in the young stalagmites were difficult to apply 23 Th-230/U dating. Instead, AMS 14C dating solved the chronological problem of these stalagmites. Both stalagmites had fast growth rates during Holocene Optimum and the last 600 years, but absent growth between 4 and 8 ka. The delta O-18 record of Stalagmite 20120824-13 agrees well with the Dongge delta O-18 records on centennial or longer scales, showing dry climates during the Last Glacial Maximum (LGM) and Younger Dryas and wet climates during Holocene Optimum following the solar insolation trend. The summer monsoon strength decreased from 4.12 ka to 1.5 ka, but increased during the Medieval Warm Period to produce wet climates and abundant vegetation in the study area. The delta O-18 record during the last 600 years exhibits strongly decadal variations. Twelve light delta(18) O excursions on decadal scales during the last 600 years can be identified, agreeing with the local Dry-Wet index record. The Pacific Decadal Oscillation (PDO) strongly affects decadal variability of the moisture budget in the study area, with cold PDO (La Nifia condition) in favor of stronger EASM and wet climates. The delta C-13 record indicates that natural vegetation in the study area was strongly destroyed by human activity after the reign of Emperor Yong Zheng (AD 1722-1735) of Qing Dynasty. Since then, the karst-desertification in central Guizhou has been strongly developed due to rapidly increased population and land-use. (c) 2015 Elsevier Ltd. All rights reserved.

Publication name	JOURNAL OF ASIAN EARTH SCIENCES, 114 549-561; SI 10.1016/j.jseaes.2015.07.021 3 DEC 15 2015
Author(s)	Zhao, Min; Li, Hong-Chun; Liu, Zai-Hua; Mii, Horng-Sheng; Sun, Hai-Long; Shen, Chuan-Chou; Kang, Su-Chen
Corresponding author	LI Hongchun hcli1960@ntu.edu.tw POB 13-318,1,Sec 4,Roosevelt Rd, Taipei 106, Taiwan.
Author(s) from IGCAS	ZHAO Min, LIU Zaihua, SUN Hailong

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