FANG Moqin1,2,YANG Xunlin1,2,LIU Xiuming3,LYU Chunyan1,2,CUI Guyue1,2, SUN Xili1,2, SHI Zhichao1,2
(1. School of Geographical Sciences, Southwest China University, Chongqing 400715, China;
2. Karst Environment Laboratory, Southwest University, Chongqing 400715, China；
3. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China)
Abstract: Heifeng Cave (28°50′-29°20′N, 107°00′-107°20′E; 1980m above sea value) is located on the north slope of the Jinfo Mountains, and the climate here is controlled by Asian monsoon system, with abundant rainfall and high temperature in summer. Stalagmite HF01 in Heifeng Cave was collected as the research subject in this paper. Based on the 230Th dating results, grey value data, oxygen isotope data and trace elements data, the grey scale time series of the stalagmite HF01 grown during the Holocene was established. Results suggest that the grey value of stalagmite HF01 is controlled by the East Asian monsoon variability. The main trend of Holocene climate change is: in the early and middle Holocene, the summer monsoon of North Hemisphere increased gradually, and in late Holocene decreased continually; this change of stalagmite HF01 is reflected from both the evolution of δ18O value and the grey value of stalagmite. The grey scale of HF01 stalagmites responses to 8 cold events of the North Atlantic record, indicating that the grey value of stalagmite is closely associated with variations in past climates and environments. Using the spectral analysis of Redfit 37, the main cycles of stalagmite records from grey scale are 55a, 45a, 40a, 33a, 25a, 23a, 22a, 18a, 16a, 14a and 12a. The 55a cycle may be related to the Pacific Decadal Oscillation (PDO), and 45a, 25a, 23a, 22a, 18a, and 12a cycles agree well with the solar activity, suggesting that the Pacific Decadal Oscillation (PDO) and solar activity changes may be partly responsible for centennial-decadal changes in East Asian monsoon.
Keywords: stalagmite; grey value; Asian monsoon; solar activity; Holocene
EARTH AND ENVIRONMENT Vol.45, No.2, Tot No.316, 2017, Page 126-134
