气候变化领域集成服务门户(CCPortal): 黄土高原西部地区黄土粒度的环境指示意义

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	黄土高原西部地区黄土粒度的环境指示意义
其他题名	Environmental Significance of Grain Size of Loess-paleosol Sequence in Western Part of Chinese Loess Plateau
	汪海斌; 陈发虎; 张家武
发表日期	2002
ISSN	1000-694X
卷号	22 期号:1 页码:21-26
中文摘要	通常把＞30mum颗粒含量作为冬季风的替代指标。对黄土高原西部地区的兰州九州台剖面、西宁土巷道剖面粒度主成分和聚类分析表明：＞40mum颗粒的含量是黄土高原西部地区更为敏感的古冬季风替代指标，＜2mum颗粒的含量的变化所指示的古气候意义可能与黄土高原中部地区不同。
英文摘要	Chinese loess paleosol sequence has provided some the most detailed terrestrial records of climate changes in Quaternary. Grain size and magnetic susceptibility have proved to be good proxies of East Asian Winter Monsoon and Summer Monsoon variations respectively. Studies on loess sections through Loess Plateau in Central China suggested that > 30 mum size fraction is a sensitive proxy of winter monsoon strength for central part of loess plateau. However, one thing that should be reemphasized is that grain size distribution becomes finer leeward, from northwest through southeast, gradually on Chinese Loess Plateau. Therefore >30 mum size fraction should be argued when it was issued as an indicator of winter monsoon strength of west Chinese Loess Plateau. While western part of Chinese Loess Plateau has great potentials to provide much higher-resolution climatic records than Central Chinese Loess Plateau does. So it is necessary to find out a sensitive proxy of winter monsoon strength for West Chinese Loess Plateau. This paper focuses on discussing grain size distribution characteristics of two typical loess sections, Tux-iangdao Section in Xining and Jiuzhoutai Section in Lanzhou > on West Chinese Loess Plateau so as to obtain related climatic information and appropriate proxy of winter monsoon strength.Using SPSS for Window 8.0, we conduct Principal Component Analysis on amounts of size distribu-tion data of these two Loess sections. Output accomplished with SPSS shows that the cumulative loading of the initial three components of Jiuzhoutai section and Tuxiangdao section accounts for 95. 37%, 96. 07% respectively, which suggests that these three extracted principal components are fully credible. Results al-so indicate that the first component and the third component is linked to winter monsoon variation in Ji-uzhoutai section; while the first component and the second component is related to winter monsoon varia-tion in Tuxiangdao section. To determine candidate for winter monsoon strength proxy, we employ classif-ying analysis that is a useful way to tell threshold value. The threshold level is 40. 2 ～ 43. 9 mum in Ji-uzhoutai section and 38. 9~42. 6 mum in Tuxiangdao section. Therefore, we conclude that coarser size frac-tion >40 mum is a proper indicator of winter monsoon strength for west Chinese Loess Plateau.
关键词	风尘冬季风古气候主成分分析黄土高原黄土粒度
英文关键词	eolian dust;winter monsoon;paleoclimate;principal component;analysis
语种	中文
WOS研究方向	Mineralogy
WOS类目	MINERALOGY
CSCD记录号	CSCD:1078071
来源期刊	中国沙漠
来源机构	兰州大学 ; 中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/1865
推荐引用方式 GB/T 7714	汪海斌,陈发虎,张家武. 黄土高原西部地区黄土粒度的环境指示意义[J]. 兰州大学, 中国科学院青藏高原研究所,2002,22(1):21-26.
APA	汪海斌,陈发虎,&张家武.(2002).黄土高原西部地区黄土粒度的环境指示意义.中国沙漠,22(1),21-26.
MLA	汪海斌,et al."黄土高原西部地区黄土粒度的环境指示意义".中国沙漠 22.1(2002):21-26.