• 论文 •

### 祁连山东段全新世与现代水热组合特征研究

1. 兰州大学地理系 甘肃兰州730000
• 收稿日期:1999-04-27 修回日期:1999-12-27 出版日期:2000-03-20 发布日期:2000-03-20
• 基金资助:
国家自然科学基金(49731010);教育部重点项目

### Study on Hydro-Thermal Characteristic of Eastern Qilian Mountains in Holocene and Present

WU Guang-jian, PAN Bao-tian, GUANG Qing-yu, LIU Zhi-gang, WANG Yi-xiang

1. Department of Geography, Lanzhou University, Lanzhou, Gansu, 730000
• Received:1999-04-27 Revised:1999-12-27 Online:2000-03-20 Published:2000-03-20

Abstract: Biandukou and Haxi section recorded climatic changes in Holocene, Eastern Qilian Mountains. Susceptibility, organic carbon content and CaCO3 content are used as excellent proxies to summer monsoon, mainly the precipitation. Compared with the Dunde ice-core record, used as the thermal proxy, here we can rebuild the hydro-thermal characteristic in Holocene in this region. During the 7.2-6.0 Ka B. P., in eastern China and many other regions, climate characteristic was high temperature and high precipitation. But, in eastern Qilian Mountains, this period was not the optimum, it’s only relatively suitable. The climate optimum took place during 5.2-4.0 ka B. P., not in the same time with Megathermal Maximum. Significant environment deterioration took place in 4.0 ka B. P. and 3.0 ka B. P., but the former was more distinct than the latter. So we took 4.0 ka B. P. as the boundary of the middle Holocene and the late. Changes of ancient civilizations serviced as another proof for climatic changes. In 2.0-1.0 ka B. P., scores of climatic proxies showed another climate suitable period, but the leaching depth of CaCO3 was shallow and the Dunde ice-core recorded the drop of temperature. Analysis of modern weather data shows that humidity has an incline to drop beyond a certain high temperature in arid and semi-arid region. While in subhumid regions, humidity increases with the increase of temperature and this may give the possibility of the assembly of high temperature and high humidity as now as in the middle Holocene(7.2-6.0 ka B. P.). Environment qualities in arid and semi-arid regions mainly depend on water since it is the most important in all the factors. So temperature and humidity would not reach their maximum simultaneously in the studied area.

• P532