Carbon isotopic composition of modern soil and paleosol as a response to vegetation change on the Chinese Loess Plateau  

作　　者：LIU Weiguo NING Youfeng AN Zhisheng WU Zhenghai LU Huayu CAO Yunning 

机构地区：[1]State Key Laboratory of Loess and Quaternary Geology, IEE, Chinese Academy of Sciences, Xi'an 710075, China State Key Laboratory of Loess and Quaternary Geology, IEE, Chinese Academy of Sciences, Xi'an 710075, China State Key Laboratory of Loess and Quaternary Geology, IEE, Chinese Academy of Sciences, Xi'an 710075, China Northwest Sci-Tech University of Agriculture and Forest, Yangling 710000, China State Key Laboratory of Loess and Quaternary Geology, IEE, Chinese Academy of Sciences, Xi'an 710075, China State Key Laboratory of Loess and Quaternary Geology, IEE, Chinese Academy of Sciences, Xi'an 710075, China

出　　处：《Science China Earth Sciences》2005年第1期93-99,共7页中国科学（地球科学英文版）

基　　金：This research was supported by the Chi-nese Academy of Sciences(Grant Nos.KZCX2-SW-118);the National Natural Science Foundation of China(Grant Nos.40373008 and 40121303);the foundation for the Author of National Excellent Doctonl Dissertation of China

摘　　要：The relationship between the carbon isotopic composition of paleosols and paleovegetation on the Loess Plateau is still unclear. One of the main reasons is that we are short of knowledge about the characteristics of the carbon isotopic composition of modern soil in this area. A preliminary investigation of the carbon isotopic compositions of the modern soil and the loess/paleosol sequence on the Loess Plateau shows that the carbon isotopic composition of modern soil is consistent with the distribution of modern plants on the Loess Plateau, where the ecosystem is dominated by a mixture of C4 and C3 plants. Comparing theδ13C values of modern soil and loess-paleosol sequences from the Xunyi profile, we conclude that C3 plants dominated the landscape during loess sediment stages, while C4 plants expanded during paleosol stages.The relationship between the carbon isotopic composition of paleosols and pale-ovegetation on the Loess Plateau is still unclear. One of the main reasons is that we are short of knowledge about the characteristics of the carbon isotopic composition of modern soil in this area. A preliminary investigation of the carbon isotopic compositions of the modern soil and the loess/paleosol sequence on the Loess Plateau shows that the carbon isotopic composition of modern soil is consistent with the distribution of modern plants on the Loess Plateau, where the ecosystem is dominated by a mixture of C4 and C3 plants. Comparing the δ13C values of modern soil and loess-paleosol sequences from the Xunyi profile, we conclude that C3 plants dominated the landscape during loess sediment stages, while C4 plants expanded during paleosol stages.

关 键 词：MODERN soil  paleosol  carbon isotope  paleovegetation  LOESS Plateau. 

分 类 号：N[自然科学总论]