The Spatial and Time Scales for the Dry Mid-Holocene Event in Zhuye Lake

详细信息   

• 责任者：Li Yu(College of Earth and Environmental Sciences ; Center for Hydrologic Cycle and Water Resources in Arid Region ; Lanzhou University ; Lanzhou ; Gansu 730000 ; China) ; Wang Naiang
• 刊名：Scientia Geographica Sinica
• 出版年：2012
• 卷期：32(6)
• 页码：p.731-738
• issnNo：ISSN1000-0690
• isbnNo：CN22-1124/P

摘要

In this paper, the sediments and paleo-lakeshores data in Zhuye Lake and surrounding areas, the terminal lake of Shiyang River drainage basin, in the marginal area of the Asian monsoon, were synthesized and then the spatial and time scales around Zhuye Lake and in the drainage basin were discussed. In the spatial scale, this study compared the results of mid-Holocene geomorphology and lake sediments in Zhuye Lake, and we also studied the mid-Holocene sections in the middle and upper regions of the Shiyang River. In the time scale, nearly a hundred dating results in Zhuye Lake and the drainage basin were compared. Then it was concluded that there was a centennial-scale extremely dry interval occurring during 8.0-7.0 cal ka B.P. in Zhuye Lake, instead of the previous study which reported the dry interval during 7000-5000 cal a B.P.. And the centennial- scale extremely dry could be detected in the middle and lower reaches of the drainage basin, but the upper region was less affected. The centennial-scale extremely dry interval might be related to the changes in water and heat balance, and the characteristics of climatic conditions in this drainage lead to the different responses to the dry interval in the different locations of the drainage basin. There were no obvious evidences showing that the dry interval was related to the Asian monsoon weakening. In this paper, the time and spatial scales analysis of the dry mid-Holocene in Zhuye Lake provide some clues and ideas for the dry mid-Holocene studies in other parts of the Asian monsoon domain.