干旱区生态环境知识资源中心(Arid): 青土湖地区9 500 a BP以来的环境变化研究

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	青土湖地区9 500 a BP以来的环境变化研究
其他题名	Environmental Change around the Qingtu Lake since 9 500 a BP
	赵强 1; 王乃昂1 ; 李秀梅 2; 程弘毅 1; 李育 1; 李钢 1
来源期刊	冰川冻土
ISSN	1000-0240
出版年	2005
卷号	27 期号:3 页码:352-359
中文摘要	通过对青土湖地区ZY剖面的代用指标分析, 研究了该区9 500 a BP以来的气候环境变化. 在9 500～6 700 a BP期间, 剖面为风成砂沉积, 平均粒径、磁化率、碳酸盐含量和C/N代用指标值均出现了的最低值, 代表了湖泊干涸状态下强烈的风力搬运堆积, 反映为一种暖干的古气候环境;6 700 ～5 800 a BP期间, 为碳酸盐粉砂质粘土沉积, 代用指标的值均为高值, 指示高水位、暖湿的古气候环境;5 800～2 700 a BP为碳酸盐粉砂沉积, 代用指标的值均表现为中等, 代表了低水位状态下的碳酸盐沉积, 反映夏季风减弱, 区域降水量减少;2 700～1 100 a BP期间为沼泽沉积, 此时湖泊水量变化是以人为因素为主还是自然因素为主, 需要进一步研究.
英文摘要	Investigations of geomorphology and sedimentology, and analyses of radiocarbon dates i grain size, susceptibility, content of carbonate and C/N-indicates of the sediment at the present-day closed basin (Qingtu Lake) in the terminal of the Shiyang River in arid region of China were conduc-ted to recover the history of palaelake change since the Holocene. Qingtu Lake lies in Minqin basin in the east of the Hexi Corridor, which is located in the west edge of the East Asia monsoon, Through a field survey, the profile ZY is chosen as study object. Proxies of the Profile ZY, such as grain size, susceptibility, content of carbonate and C/N, reveal the variation of summer monsoon precipita- tion in the Shiyang River drainage basin during 9 500 ~ 1 100 a BP. An abrupt event happened during 9 500 ~ 6 700 a BP, when climate was droughty and windy, with sands depositing; Dur-ing 6 700-’5 800 a BP summer monsoon strongly impacted the region, and precipitation was abun-dant, atmosphere was humid, lakes were deeper! During 5 800 ~ 2 700 a BP summer monsoon be-came unsteady, so was water level of lakes, with frequently fluctuating climate; During 2 700 - 1 100 a BP human activity increased obviously and water level of lakes declined continuously, so it is necessary to study whether the natural factors were the key to control the water level.
中文关键词	青土湖 ; 东亚夏季风 ; 代用指标
英文关键词	Qingtu Lake East Asia summer monsoon proxy
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOLOGY
WOS研究方向	Geology
CSCD记录号	CSCD:1995393
来源机构	兰州大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/205921
作者单位	1.兰州大学,资源环境学院地理科学系, 兰州, 甘肃 730000, 中国; 2.兰州大学,资源环境学院地理科学系, 甘肃 730000, 中国
推荐引用方式 GB/T 7714	赵强,王乃昂,李秀梅,等. 青土湖地区9 500 a BP以来的环境变化研究[J]. 兰州大学,2005,27(3):352-359.
APA	赵强,王乃昂,李秀梅,程弘毅,李育,&李钢.(2005).青土湖地区9 500 a BP以来的环境变化研究.冰川冻土,27(3),352-359.
MLA	赵强,et al."青土湖地区9 500 a BP以来的环境变化研究".冰川冻土 27.3(2005):352-359.