干旱区生态环境知识资源中心(Arid): Geochemistry of soils of a deep pedon in the Okavango Delta, NW Botswana: Implications for pedogenesis in semi-arid regions

Arid

DOI	10.1016/j.geodrs.2020.e00352
	Geochemistry of soils of a deep pedon in the Okavango Delta, NW Botswana: Implications for pedogenesis in semi-arid regions
	Eze, Peter N.; Molwalefhe, Loago N.; Kebonye, Ndiye M.
通讯作者	Eze, PN (corresponding author), Botswana Int Univ Sci & Technol, Dept Earth & Environm Sci, Private Bag 16, Palapye, Botswana.
来源期刊	GEODERMA REGIONAL
ISSN	2352-0094
出版年	2021
卷号	24
英文摘要	Pedogenic parameters and data on geochemical compositions were analysed to improve our understanding of pedogenesis and soil morphology in an ecologically and geologically unique and relatively quiescent tectonic setting of the Okavango Delta, northern Botswana. A complex interaction of pedogenic and gradational processes in the area resulted in the formation of a deep (similar to 4 m) pedon with three distinct morphologies: a weakly structured surface horizon, modern pedogenic carbonate enriched B horizons at stage III development and slightly pedogenically altered sediment C horizons. The pH ranged from 8.1 to 10.0 implying alkaline soil environment, while electrical conductivity ranged from 2 to 55 dS/cm. Gleying, an evidence hydromorphism, was present in the wetting front (C horizon). Results of the total elemental composition show the dominance of silica followed by CaO, Al2O3, MgO and Fe2O3 as the major oxides. Trace elements had lower HFSE (e.g. Zr and Nb) than LILE (e.g. Ba, Sr, Rb, Cr and V) contents. Calcite, quartz and opal-CT are the minerals present in the fine silt and clay fractions of the soils. Geochemical indicators points to incipient weathering and pedogenesis. Evolutionary accumulation of pedogenic carbonate in the diagnostic horizons bestows Calcisols as the Reference Soil Group and not Arenosols as previously known. Other pedogenic processes including leaching losses, redox processes and salt accumulation were strongly influenced by the saline groundwater processes. By comparing these site-specific findings with examples from other settings, this study has demonstrated the applicability of morphological, geochemical and mineralogical properties of soils in assessing pedogenic processes and classification in deep calcic soils associated with alluvial and aeolian depositions. (C) 2020 Elsevier B.V. All rights reserved.
英文关键词	Calcisols Kalahari Basin Pedogenic carbonates Opal-CT Redoximorphism
类型	Article
语种	英语
开放获取类型	Bronze
收录类别	SCI-E
WOS记录号	WOS:000621429700014
WOS类目	Soil Science
WOS研究方向	Agriculture
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/350387
作者单位	[Eze, Peter N.; Molwalefhe, Loago N.] Botswana Int Univ Sci & Technol, Dept Earth & Environm Sci, Private Bag 16, Palapye, Botswana; [Kebonye, Ndiye M.] Czech Univ Life Sci, Fac Agrobiol Food & Nat Resources, Dept Soil Sci & Soil Protect, Kamycka 129, Prague 16500 6, Czech Republic
推荐引用方式 GB/T 7714	Eze, Peter N.,Molwalefhe, Loago N.,Kebonye, Ndiye M.. Geochemistry of soils of a deep pedon in the Okavango Delta, NW Botswana: Implications for pedogenesis in semi-arid regions[J],2021,24.
APA	Eze, Peter N.,Molwalefhe, Loago N.,&Kebonye, Ndiye M..(2021).Geochemistry of soils of a deep pedon in the Okavango Delta, NW Botswana: Implications for pedogenesis in semi-arid regions.GEODERMA REGIONAL,24.
MLA	Eze, Peter N.,et al."Geochemistry of soils of a deep pedon in the Okavango Delta, NW Botswana: Implications for pedogenesis in semi-arid regions".GEODERMA REGIONAL 24(2021).