Pedogenesis, permafrost, substrate and topography: Plot and landscape   scale interrelations of weathering processes on the central-eastern   Tibetan Plateau

doi:10.1016/j.geoderma.2014.02.019

CORC > 北京大学 > 城市与环境学院

	Pedogenesis, permafrost, substrate and topography: Plot and landscape scale interrelations of weathering processes on the central-eastern Tibetan Plateau
	Baumann, Frank ; Schmidt, Karsten ; Doerfer, Corina ; He, Jin-Sheng ; Scholten, Thomas ; Kuehn, Peter
刊名	geoderma
	2014
关键词	Tibetan Plateau Pedogenesis Permafrost Weathering indices Pedogenic oxides Multiple linear regression ESTIMATING RELATIVE AGES LOESS-PALEOSOL SEQUENCE IRON-OXIDE MINERALOGY WESTERN PO VALLEY CLIMATIC-CHANGE SOILS CHINA ROCKS GEOCHEMISTRY SEDIMENTS
DOI	10.1016/j.geoderma.2014.02.019
英文摘要	Weathering indices (WI) and pedogenic oxides ratios (POR) were used to describe patterns of weathering intensities and pedogenesis along climatic gradients, mainly affected by varying influences of the Asian and Indian Monsoon. These climate settings induce particular soil moisture (SM) conditions, in turn closely related to permafrost state, substrate, and topography. Nine sites including a total of 30 soil profiles were examined along an eastern and a western transect across the central-eastern Qinghai-Tibet Plateau. Additionally, differences between four soil groups were analysed. According to our knowledge, the presented study is the first attempt of a comprehensive application of different WI and POR to substrates of currently permafrost-affected soils. It provides an evaluation of various tools in terms of chemically describing and differentiating the related processes to distinct environmental settings in low-weathering regions. We found that weathering trends along the climatic gradients could be clearly outlined by WI, whereas POR rather account for small scale variations, describing significant differences of pedogenesis between continuous and discontinuous permafrost conditions. Pyrophosphate soluble iron (Fep) proved to be useful for differentiating permafrost and ground water influenced soils, showing a strong correlation to total organic carbon (r = 0.89). The chemical index of alteration (CIA) is the most suitable WI, whereas Ca-free CPA is more easily biased by salinity variations of topsoils at sites with negative water balance, thus pretending lower weathering intensities. Regression analyses for WI and POR with main independent variables underline the specific characteristics: climatic parameters best explain WI, while SM is dominant for POR. The ratio (Fed-Feo)/Fet proved as the most appropriate POR with 64% explained variation by a multiple linear regression model, implying significantly lower iron release with higher SM and pH values. Variation of Fep can be explained by 63% with soil acidity being most important followed by SM. Importantly, the presented research provides tools for investigating past and future stability or respective degradation processes of permafrost ecosystems on the Tibetan Plateau and may be applicable to other permafrost-affected environments. (C) 2014 Elsevier B.V. All rights reserved.; Soil Science; SCI(E); EI; 3; ARTICLE; frank.baumann@uni-tuebingen.de; 1; 300-316; 226
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/211024]
专题	城市与环境学院
推荐引用方式 GB/T 7714	Baumann, Frank,Schmidt, Karsten,Doerfer, Corina,et al. Pedogenesis, permafrost, substrate and topography: Plot and landscape scale interrelations of weathering processes on the central-eastern Tibetan Plateau[J]. geoderma,2014.
APA	Baumann, Frank,Schmidt, Karsten,Doerfer, Corina,He, Jin-Sheng,Scholten, Thomas,&Kuehn, Peter.(2014).Pedogenesis, permafrost, substrate and topography: Plot and landscape scale interrelations of weathering processes on the central-eastern Tibetan Plateau.geoderma.
MLA	Baumann, Frank,et al."Pedogenesis, permafrost, substrate and topography: Plot and landscape scale interrelations of weathering processes on the central-eastern Tibetan Plateau".geoderma (2014).