• 责任者：Li Pingyuan (Key Laboratory of Western China’s Environmental Systems ; Ministry of Education ; Research School of Arid Environment ＆ Climate Change ; Lanzhou University ; Lanzhou 730000 ; China) ; Liu Xiuming
• 刊名：Quaternary Sciences
• 出版年：2013
• 卷期：33(2)
• 关键词：磁化率 ; magnetic susceptibility ; 黄土 ; loess ; 黄土高原 ; Loess Plateau
• 页码：p.360-367
• 图表：illus., 1 table, 44 refs.
• 分类号：1400
• issnNo：ISSN1001-7410
• isbnNo：CN11-2708/P

The magnetic susceptibility variation of loess-paleosol sequences in Chinese Loess Plateau （CLP） coincides with paleoclimatic changes and hence is widely used for climate reconstruction. Previous studies indicate the existence of a linear relationship between precipitation and magnetic susceptibility of topsoil, which is, however, speculated more complicated.  Here we study topsoil（ 170 samples and together with other 61 published）including Gobi and CLP in northwest of China, spanning 96° - 110°E ,33°N to 43°N, with precipitation 50 - 700mm/a. Low field magnetic susceptibility Elf and frequency dependent susceptibility （Xfa and Zfd% ） have been obtained using Bartington MS2. The precipitation,ranging from 1971 -2000,at each sample site is simulated and determined with GIS methods.  The correlation between magnetic susceptibility and precipitation presented in this study indicates that： linear relationship between susceptibility and precipitation only occurs to a high precipitation larger than 200mm/a and 300mm/a. Below this threshold,the relationship is unintelligible. This relation boundary likely attributes to different pedogensis degree over this area. Superparamagnetic （SP）particles bearing very high susceptibility form during the strong pedognesis in humid area; while in arid area due to weak pedogenic process,the contribution of SP particles of pedogensis origin is limited.