The distribution of organic carbon fractions in a typical loess-paleosol profile and its paleoenvironmental significance

doi:10.7717/peerj.4611

CORC > 水土保持研究所 > 中国科学院水利部水土保持研究所 > 水保所2018届毕业生论文

	The distribution of organic carbon fractions in a typical loess-paleosol profile and its paleoenvironmental significance
	Chang Wenqian 3; Zhang Qingqing1,2 ; Huang Jinghua 2,3; Hu Feinan 2,3; Huo Na 3; Shang Yingni 3; Zhao Shiwei 2,3
刊名	Peer J
	2018-04-13
期号	6 页码:e4611
关键词	The Chunhua Loess-paleosol Sequence Grain Size Paleoclimate Moc/toc Caco3
DOI	10.7717/peerj.4611
英文摘要	Background. The loess-paleosol sequence on the Loess Plateau has been considered an important paleoclimatic archive to study global climatic and environmental changes in the Quaternary. So far, little attention has been paid to the characteristics of soil organic carbon fractions in loess-paleosol sequences, which may provide valuable information for exploring the evolution of climate and environment in the Quaternary on the Loess Plateau. Methods. In order to explore the significance of mineral-associated organic carbon to total organic carbon (MOC/TOC) ratios in the loess-paleosol sequence for reconstruct- ing paleoenvironmental and paleoclimatic evolution in the Quaternary on the Loess Plateau, we selected a typical loess-paleosol profile in Chunhua county, Xianyang city, Shaanxi province, as the research object. The content of total organic carbon (TOC) and MOC/TOC ratio in each loess and paleosol layers of the Chunhua loess-paleosol profile were analyzed, together with the paleoclimatic proxies, such as soil grain size, CaCO3 content and their correlations with organic carbon parameters. Results. The main results were as follows: (1) the total content of soil organic carbon and MOC/TOC ratios were generally higher in paleosol layers than in the underlying loess layers of the Chunhua loess-paleosol profile. Compared to total organic carbon content, MOC/TOC ratios changed more obviously in soil layers below a paleosol layer S8; (2) soil clay content and median grain size (Md ( )) were higher in paleosol than in the underlying loess, while CaCO3 content showed an opposite tendency. In the Chunhua profile, the distribution characteristics of the three paleoclimatic proxies showed good indications of paleoclimate changes in the Quaternary; (3) in the Chunhua loess-paleosol profile, MOC/TOC ratios were positively correlated with clay content and median grain size ( ), while negatively correlated with CaCO3 content, and the correlations were more significant in soil layers below S8. Discussion. Our results indicated that MOC/TOC ratios in the Chunhua loess-paleosol profile correlated with the cold dry-warm wet paleoclimatic cycle in the Quaternary. The high MOC/TOC ratios in the loess-paleosol profile might reflect warm and humid climate, while lower ratios indicated relatively cold and dry climate. That is because when the climate changed from warm-humid to cold-dry, the vegetation coverage and pedogenesis intensity decreased, which increased soil CaCO3 content and decreased soil clay content and Md ( ), leading to decreased MOC/TOC ratios. Compared to TOC, MOC/TOC ratios had greater significance in indicating paleoenvironmental evolution in the Quaternary on the Loess Plateau. Therefore, investigating MOC/TOC ratios in loess-paleosol profile can offer new evidence to reconstructing paleoenvironmental changes, and also provide a basis for predicting responses of soil organic carbon pools to vegetation and climate changes in the future.
学科主题	农学
会议日期	0
语种	英语
资助机构	This work was supported by the National Science Foundation of China (No.31500449), West Light Foundation of the Chinese Academy of Sciences (No.XAB2015B05), Open Fund of State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources (No.A314021402-1515), and the Fundamental Research Funds for the Central Universities (No.2452016101). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; This work was supported by the National Science Foundation of China (No.31500449), West Light Foundation of the Chinese Academy of Sciences (No.XAB2015B05), Open Fund of State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources (No.A314021402-1515), and the Fundamental Research Funds for the Central Universities (No.2452016101). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; This work was supported by the National Science Foundation of China (No.31500449), West Light Foundation of the Chinese Academy of Sciences (No.XAB2015B05), Open Fund of State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources (No.A314021402-1515), and the Fundamental Research Funds for the Central Universities (No.2452016101). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; This work was supported by the National Science Foundation of China (No.31500449), West Light Foundation of the Chinese Academy of Sciences (No.XAB2015B05), Open Fund of State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources (No.A314021402-1515), and the Fundamental Research Funds for the Central Universities (No.2452016101). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
内容类型	期刊论文
源URL	[http://ir.iswc.ac.cn/handle/361005/8122]
专题	水保所2018届毕业生论文
通讯作者	Zhao Shiwei
作者单位	1.University of Chinese Academy of Sciences 2.State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources 3.State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University
推荐引用方式 GB/T 7714	Chang Wenqian,Zhang Qingqing,Huang Jinghua,et al. The distribution of organic carbon fractions in a typical loess-paleosol profile and its paleoenvironmental significance[J]. Peer J,2018(6):e4611.
APA	Chang Wenqian.,Zhang Qingqing.,Huang Jinghua.,Hu Feinan.,Huo Na.,...&Zhao Shiwei.(2018).The distribution of organic carbon fractions in a typical loess-paleosol profile and its paleoenvironmental significance.Peer J(6),e4611.
MLA	Chang Wenqian,et al."The distribution of organic carbon fractions in a typical loess-paleosol profile and its paleoenvironmental significance".Peer J .6(2018):e4611.