Carbon and oxygen isotopes of calcified root cells, carbonate nodules and total inorganic carbon in the Chinese loess-paleosol sequence: The application of paleoenvironmental studies

doi:10.1016/j.jseaes.2020.104515

IEECAS OpenIR

	Carbon and oxygen isotopes of calcified root cells, carbonate nodules and total inorganic carbon in the Chinese loess-paleosol sequence: The application of paleoenvironmental studies
	Luo, Xi 1,2; Wang, Hong 1,3; An, Zhisheng 1,4; Zhang, Zeke 1; Liu, Weiguo 1,4
通讯作者	Liu, Weiguo(liuwg@loess.llqg.ac.cn)
	2020-10-01
发表期刊	JOURNAL OF ASIAN EARTH SCIENCES
ISSN	1367-9120
卷号	201 页码:8
摘要	The continuous loess-paleosol sequence on the Chinese Loess Plateau (CLP) is a major terrestrial archive of paleoclimate changes. The carbon and oxygen isotopes of soil carbonate in the sequence have long been applied to reconstruct Quaternary climate changes, yet which soil carbonates has the integrity to signify the climate variability still remains a controversy. Hence, in this study, we compared carbon and oxygen isotopic compositions of soil inorganic carbon (TIC), carbonate nodules, and calcified root cells (CRCs) found in the Xifeng loess profile on the CLP to test their significance as paleoclimate indicators. The X-ray diffraction and scanning electron microscope analysis performed on CRCs prove that they are pure micro-scale calcite minerals with distinct epidermal cell structures of plant rootlets. The results of C-14 dating show that CRCs and nodules have evident translocation of younger carbon while the TIC appears more or less consistent with the model ages. The delta C-13(CRC) values vary from -18.2 parts per thousand to -11.6 parts per thousand, while the delta O-18(CRC) values range from -13.7 parts per thousand to -9.2 parts per thousand on the V-PDB scale, spanning 6.6 parts per thousand and 4.5 parts per thousand, respectively. The contrast shows that delta C-13(CRC) values are more negative than those of nodules and TIC, and the delta C-13(CRC) values disperse within a large spectrum, which reflects a rapid germination of root cell calcification with little or even no time for diffusion process within individual C-3 plant roots. We argue that pure secondary micro carbonates like CRCs are closely associated with the plant-genic carbon. Their isotope values carry seasonal or even single event-based climate signals. Our study also suggests that stable isotope compositions of carbonate nodules and TIC are interfered by primary carbonate minerals. Thus, it should be used with caution when applying those materials for researches of paleoclimate changes.
关键词	Stable carbon isotope Calcified root cells C-14 age Paleoclimate Chinese Loess Plateau
DOI	10.1016/j.jseaes.2020.104515
关键词[WOS]	EARTHWORM CALCITE GRANULES ; ASIAN SUMMER MONSOON ; PEDOGENIC CARBONATE ; SECONDARY CARBONATES ; DELTA-C-13 VALUES ; NORTHERN CHINA ; MODERN SOIL ; PLEISTOCENE ; RECORD ; C-4
收录类别	SCI ; SCI
语种	英语
资助项目	Chinese Academy of Sciences[XDB40000000] ; Chinese Academy of Sciences[QYZDY-SSW-DQC001]
WOS研究方向	Geology
项目资助者	Chinese Academy of Sciences
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000568796600020
出版者	PERGAMON-ELSEVIER SCIENCE LTD
引用统计	被引频次：7[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.ieecas.cn/handle/361006/15327
专题	中国科学院地球环境研究所
通讯作者	Liu, Weiguo
作者单位	1.Chinese Acad Sci, State Key Lab Loess & Quaternary Geol, Inst Earth Environm, Xian 710061, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Beijing Normal Univ, Interdisciplinary Res Ctr Earth Sci Frontier, Beijing 100875, Peoples R China 4.CAS Ctr Excellence Quaternary Sci & Global Change, Xian 710061, Peoples R China
推荐引用方式 GB/T 7714	Luo, Xi,Wang, Hong,An, Zhisheng,et al. Carbon and oxygen isotopes of calcified root cells, carbonate nodules and total inorganic carbon in the Chinese loess-paleosol sequence: The application of paleoenvironmental studies[J]. JOURNAL OF ASIAN EARTH SCIENCES,2020,201:8.
APA	Luo, Xi,Wang, Hong,An, Zhisheng,Zhang, Zeke,&Liu, Weiguo.(2020).Carbon and oxygen isotopes of calcified root cells, carbonate nodules and total inorganic carbon in the Chinese loess-paleosol sequence: The application of paleoenvironmental studies.JOURNAL OF ASIAN EARTH SCIENCES,201,8.
MLA	Luo, Xi,et al."Carbon and oxygen isotopes of calcified root cells, carbonate nodules and total inorganic carbon in the Chinese loess-paleosol sequence: The application of paleoenvironmental studies".JOURNAL OF ASIAN EARTH SCIENCES 201(2020):8.