DOI: 10.1016/j.quascirev.2018.05.022
Scopus记录号: 2-s2.0-85047499305
论文题名: Pedo-sedimentary constituents as paleoenvironmental proxies in the Sudano-Sahelian belt during the Late Quaternary (southwestern Chad Basin)
作者: Diaz N. ; Dietrich F. ; Sebag D. ; King G.E. ; Valla P.G. ; Durand A. ; Garcin Y. ; de Saulieu G. ; Deschamps P. ; Herman F. ; Verrecchia E.P.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2018
卷: 191 起始页码: 348
结束页码: 362
语种: 英语
英文关键词: Monsoon
; Optical methods
; Pedogenic carbonate nodules
; Quaternary
; Radiogenic isotopes
; Soil water balance
; Vertisol genesis
; Western Africa
Scopus关键词: Carbonation
; Erosion
; Feldspar
; Geochronology
; Luminescence
; Organic carbon
; Soil moisture
; Stratigraphy
; Monsoon
; Optical methods
; Pedogenic carbonates
; Quaternary
; Radiogenic isotopes
; Soil water balance
; Vertisols
; Western Africa
; Sedimentology
; anthropogenic effect
; carbonate sediment
; monsoon
; numerical method
; paleoenvironment
; parent material
; precipitation (chemistry)
; proxy climate record
; Quaternary
; radiocarbon dating
; radionuclide
; satellite imagery
; semiarid region
; soil erosion
; soil organic matter
; tropical region
; vegetation cover
; Vertisol
; water budget
; Cameroon
; Chad Basin
; Nigeria
; Sahel [Sub-Saharan Africa]
; Sudan
; West Africa
英文摘要: Climate and environmental changes since the Last Glacial Maximum in the tropical zone of West Africa are usually inferred from marine and continental records. In this study, the potential of carbonate pedo-sedimentary geosystems, i.e. Vertisol relics, to record paleoenvironmental changes in the southwestern part of Chad Basin are investigated. A multi-dating approach was applied on different pedogenic organo-mineral constituents. Optically stimulated luminescence (OSL) dating was performed on the soil K-rich feldspars and was combined with radiocarbon dating on both the inorganic (14Cinorg) and organic carbon (14Corg) soil fractions. Three main pedo-sedimentary processes were assessed over the last 20 ka BP: 1) the soil parent material deposition, from 18 ka to 12 ka BP (OSL), 2) the soil organic matter integration, from 11 cal ka to 8 cal ka BP (14Corg), and 3) the pedogenic carbonate nodule precipitation, from 7 cal ka to 5 cal ka BP (14Cinorg). These processes correlate well with the Chad Basin stratigraphy and West African records and are shown to be related to significant changes in the soil water balance responding to the evolution of continental hydrology during the Late Quaternary. The last phase affecting the Vertisol relics is the increase of erosion, which is hypothesized to be due to a decrease of the vegetation cover triggered by (i) the onset of drier conditions, possibly strengthened by (ii) anthropogenic pressure. Archaeological data from Far North Cameroon and northern Nigeria, as well as sedimentation times in Lake Tilla (northeastern Nigeria), were used to test these relationships. The increase of erosion is suggested to possibly occur between c. 3 cal ka and 1 cal ka BP. Finally, satellite images revealed similar geosystems all along the Sudano-Sahelian belt, and initial 14Cinorg ages of the samples collected in four sites gave similar ages to those reported in this study. Consequently, the carbonate pedo-sedimentary geosystems are valuable continental paleoenvironmental archives and soil water balance proxies of the semiarid tropics of West Africa. © 2018 Elsevier Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/112169
Appears in Collections: 气候减缓与适应
There are no files associated with this item.
作者单位: Institute of Earth Surface Dynamics, Faculty of Geosciences and the Environment, University of Lausanne, Geopolis, Lausanne, 1015, Switzerland; Department of Geography, Royal Holloway University of London, Egham, TW20 0EX, United Kingdom; Normandie Univ, UNIROUEN, UNICAEN, CNRS, M2C, Rouen, 76000, France; HSM, IRD, CNRS, Université de Montpellier, Montpellier, France; Institute of Geological Sciences and Oeschger Centre for Climate Change, University of Bern, Switzerland; Universität Potsdam, Institute of Earth and Environmental Science, Potsdam, 14476, Germany; IRD, UMR PALOC, Paris, 75005, France; CEREGE, Aix-Marseille Université-CNRS-IRD, Marseille, 13284, France
Recommended Citation:
Diaz N.,Dietrich F.,Sebag D.,et al. Pedo-sedimentary constituents as paleoenvironmental proxies in the Sudano-Sahelian belt during the Late Quaternary (southwestern Chad Basin)[J]. Quaternary Science Reviews,2018-01-01,191