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Eva Lehndorff - One of the best experts on this subject based on the ideXlab platform.
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late pleistocene dust dynamics and pedogenesis in southern eurasia detailed insights from the loess profile toshan ne iran
Quaternary Science Reviews, 2018Co-Authors: Stefan Vlaminck, Manfred Frechen, Eva Lehndorff, Martin Kehl, Christian Rolf, Svenoliver Franz, Tobias Lauer, Farhad KhormaliAbstract:Abstract In southern Eurasia recurrent phases of aridization, dust source extension and enhanced Aeolian sedimentation alternated with moister intervals, promoting reduced deflation areas and dust accumulation in the context of late Pleistocene climate changes. Weathering and Soil forming intensity in this greater region are, hence, mainly governed by fluctuations in the balance between dust supply and moisture availability. Among the hitherto known sections, the Toshan loess-Soil sequence (LPS) represents a key site due to the quality of the record and the multitude of available data giving detailed insights into the timing and magnitude of dust accumulation and Soil Formation of the region. To elucidate these dynamics for much of the past 130.000 years bulk mineralogical and geochemical data are presented supplemented by a high resolution magnetic susceptibility record and by the results of a detailed micromorphological study of loess at Toshan. The last interglacial Luvisol/Phaeozem-like (∼MIS 5e) and the early glacial interstadial steppic palaeosols (∼MIS 5 c and a) are characterized by gradually increasing grain-size and decreasing degrees in decomposition of micaceous and mafic minerals. Pronounced feldspar weathering is detected in the last interglacial and modern Soils only, which formed under reduced or absent dust deposition on penultimate and last glacial loess, respectively (postsedimentary). The overall pedosedimentary conditions correspond to large scale trends of increasing drought, dust accumulation and wind strength in southern Eurasia in relation to decreasing moisture availability towards the early Pleniglacial (∼MIS 4), causing Soil Formation under ongoing dust deposition (synsedimentary). Similar intervals of synsedimentary Soil Formation are recorded during the interglacial/interstadial-stadial transitions of the early glacial and during pleniglacial (∼MIS 4 to 2) interstadials. The latter are marked by gradual increases in magnetic susceptibility, colour and decreasing texture. Conversely, silicate weathering could not be detected, suggesting that grain-size fluctuations are a primary feature. Thus, windy and arid pleniglacial conditions in southern Eurasia were interrupted by intermittent phases of synsedimentary Soil Formation, in response to short-lived and relatively moist interstadials. Although the interrelation of these incipient Soils, throughout southern Eurasia is afflicted with considerable restrictions, the oscillatory pattern of the Toshan LPS bears great similarity with millennial-scale oscillations recorded in limnic archives of western Asia.
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accelerated Soil Formation due to paddy management on marshlands zhejiang province china
Geoderma, 2014Co-Authors: Angelika Kolbl, Peter Schad, Reinhold Jahn, Wulf Amelung, Andrea Bannert, Z H Cao, Sabine Fiedler, Karsten Kalbitz, Eva Lehndorff, Cornelia MullerniggemannAbstract:Inundation of paddy Soils for submerged rice production strongly impacts Soil Formation. Here we used chronosequences with up to 2000 years of cultivation history to compare Soil Formation in non-inundated (non-paddy) cropping systems with the Formation of Soils used for paddy rice production. This approach allowed us to identify the influence of agricultural management at different stages of pedogenesis. Soil samples were taken from two chronosequences derived from uniform parent material in the coastal region of the Zhejiang Province (P.R. China). One chronosequence consisted of paddy Soils of different ages (50-2000 years), characterized by a yearly cropping sequence of rice cultivation under flooded conditions alternated with a non-inundated crop. The adjacent non-inundated (non-paddy) chronosequence was exclusively used for non-inundated crop production for 50-700 years. Lipid biomarkers revealed origin and homogeneity of the original coastal sediments and enabled the reconstruction of a consistent land use history for both chronosequences. The chronological development of Soil properties and horizons suggested that the Formation of paddy Soils can be subdivided into three phases. The initial phase of paddy Soil development takes only a few decades and is dominated by desalinization and Formation of a compacted plow pan, leading from Fluvisols to Anthraquic Cambisols. During the next centuries (second phase), the differentiation between paddy and non-paddy management becomes increasingly obvious in terms of accelerated carbonate losses and constantly increasing organic carbon concentrations in paddy topSoils. In the third stage of paddy Soil development (>= 700 years), a (trans-)Formation and redistribution of oxides is accompanied by clearly visible hydromorphic patterns in paddy subSoils, thus promoting further development from Cambisols to Hydragric Anthrosols. To account for the underlying processes we suggest modifying the depth and mottling criteria for the definitions of anthraquic and hydragric Soil horizons in the classification of the World Reference Base for Soil Resources. The non-paddy chronosequence was characterized by a low degree of Soil development in which decalcification-related processes dominated throughout 700 years of Soil Formation. Hence, Soil Formation under paddy management was accelerated relative to that under dryland cropping, even though the 2000-year-old paddy Soils lacked evidence of an advanced stage of silicate weathering, Formation of pedogenic clay minerals, or clay migration. (C) 2013 Elsevier B.V. All rights reserved.
Farhad Khormali - One of the best experts on this subject based on the ideXlab platform.
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late pleistocene dust dynamics and pedogenesis in southern eurasia detailed insights from the loess profile toshan ne iran
Quaternary Science Reviews, 2018Co-Authors: Stefan Vlaminck, Manfred Frechen, Eva Lehndorff, Martin Kehl, Christian Rolf, Svenoliver Franz, Tobias Lauer, Farhad KhormaliAbstract:Abstract In southern Eurasia recurrent phases of aridization, dust source extension and enhanced Aeolian sedimentation alternated with moister intervals, promoting reduced deflation areas and dust accumulation in the context of late Pleistocene climate changes. Weathering and Soil forming intensity in this greater region are, hence, mainly governed by fluctuations in the balance between dust supply and moisture availability. Among the hitherto known sections, the Toshan loess-Soil sequence (LPS) represents a key site due to the quality of the record and the multitude of available data giving detailed insights into the timing and magnitude of dust accumulation and Soil Formation of the region. To elucidate these dynamics for much of the past 130.000 years bulk mineralogical and geochemical data are presented supplemented by a high resolution magnetic susceptibility record and by the results of a detailed micromorphological study of loess at Toshan. The last interglacial Luvisol/Phaeozem-like (∼MIS 5e) and the early glacial interstadial steppic palaeosols (∼MIS 5 c and a) are characterized by gradually increasing grain-size and decreasing degrees in decomposition of micaceous and mafic minerals. Pronounced feldspar weathering is detected in the last interglacial and modern Soils only, which formed under reduced or absent dust deposition on penultimate and last glacial loess, respectively (postsedimentary). The overall pedosedimentary conditions correspond to large scale trends of increasing drought, dust accumulation and wind strength in southern Eurasia in relation to decreasing moisture availability towards the early Pleniglacial (∼MIS 4), causing Soil Formation under ongoing dust deposition (synsedimentary). Similar intervals of synsedimentary Soil Formation are recorded during the interglacial/interstadial-stadial transitions of the early glacial and during pleniglacial (∼MIS 4 to 2) interstadials. The latter are marked by gradual increases in magnetic susceptibility, colour and decreasing texture. Conversely, silicate weathering could not be detected, suggesting that grain-size fluctuations are a primary feature. Thus, windy and arid pleniglacial conditions in southern Eurasia were interrupted by intermittent phases of synsedimentary Soil Formation, in response to short-lived and relatively moist interstadials. Although the interrelation of these incipient Soils, throughout southern Eurasia is afflicted with considerable restrictions, the oscillatory pattern of the Toshan LPS bears great similarity with millennial-scale oscillations recorded in limnic archives of western Asia.
Talitha C Santini - One of the best experts on this subject based on the ideXlab platform.
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from tailings to Soil long term effects of amendments on progress and trajectory of Soil Formation and in situ remediation in bauxite residue
Journal of Soils and Sediments, 2018Co-Authors: Talitha C Santini, Martin V FeyAbstract:Bauxite residue is an alkaline, saline-sodic byproduct of the Bayer process for alumina production. In situ remediation of bauxite residue is a cost-effective management strategy that transforms the residue into a Soil-like medium; however, the effects of applied amendments on trajectories and progress of Soil Formation over the medium-long term are unclear. Here, we investigated how in situ remediation amendments guided the progress and trajectories of Soil Formation in bauxite residue over 20 years. Chemical and mineralogical properties of samples from a field site in Corpus Christi, Texas, were analyzed to compare the effects of three different amendments (sewage sludge, yard waste, and topSoil) on progress and trajectories of Soil Formation in bauxite residue. Bauxite residue was deposited ca. 40 years prior to sampling; amendments were applied at varying frequencies for 20 years prior to sampling. Sewage sludge was the most effective amendment for decreasing pH, EC, and total alkalinity of bauxite residue and increasing plant nutrients and exchangeable cations. Overall Soil development is in an early stage; however, incipient Soil horizons were identified from differences in chemical and mineralogical properties with depth. Although amendment type influenced the progress of Soil Formation, it did not appear to influence the overall trajectory of Soil Formation processes. Soil derived from the bauxite residue parent material is likely to progress from a spolic Technosol to a technic Cambisol and finally either a Ferralsol or Luvisol depending on organic matter dynamics. Long-term impacts of amendments were consistent with those observed in previous short-term studies, with some outcomes improving further over the long term (e.g., Na+ leaching) and were realized to a depth enabling maintenance of a vegetation cover. These outcomes provide strong support for the use of in situ remediation as an alternative to Soil capping that enables transFormation of bauxite residue to a Soil capable of supporting a self-sustaining ecosystem.
Manfred Frechen - One of the best experts on this subject based on the ideXlab platform.
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rate of Soil Formation in arenosols of dunes on spiekeroog island germany
Geoderma Regional, 2020Co-Authors: Thomas Pollmann, Sumiko Tsukamoto, Manfred Frechen, Luise GianiAbstract:Abstract This study is concerned with the rate of Soil Formation in Arenosols of dunes on the barrier island Spiekeroog at the southern North Sea coast. It focuses on Fe dynamics in the Soils in relation to slope aspect, as well as on the interaction between minerals and Soil organic matter (SOM) in the course of Soil Formation. Ten quartz-rich (≈ 95 wt%) Arenosols on slopes with different aspects (north/south), low in primary carbonates (≈ 0.5 wt%) and total Fe (Fet, ≈ 0.15 wt%), were studied across a Soil chronosequence with optically stimulated luminescence (OSL) ages between 43 ± 7 and 279 ± 26 years. During this period, pH (CaCl2) decreased from 7.1 in fresh sands to 3.1 in initially podzolized Soils. SOM contents and the optical density of oxalate extracts (ODOE) increased with Soil age. Differences in Fe stocks, vertical distribution of Fed, Feo and Fep and horizontation of equally old Soils indicated an influence of microclimate on pedogenesis determined by slope aspect. Initial podzolization features occurred after 179 ± 17 years. Eluviation resulted in the Formation of an E horizon free of amorphous and poorly crystalized Fe oxides (Feo-Fep), indicating that these oxides provided a source of Fe during podzolization. However, illuviation features were absent. Field findings, macroscopic examinations and carbon fractionations revealed, that SOM was exclusively present in free particulate form (free POM). This indicated, that prior to podzolization, mineral grains did not become enclosed by organic pigments during the Formation of Ah horizons.
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late pleistocene dust dynamics and pedogenesis in southern eurasia detailed insights from the loess profile toshan ne iran
Quaternary Science Reviews, 2018Co-Authors: Stefan Vlaminck, Manfred Frechen, Eva Lehndorff, Martin Kehl, Christian Rolf, Svenoliver Franz, Tobias Lauer, Farhad KhormaliAbstract:Abstract In southern Eurasia recurrent phases of aridization, dust source extension and enhanced Aeolian sedimentation alternated with moister intervals, promoting reduced deflation areas and dust accumulation in the context of late Pleistocene climate changes. Weathering and Soil forming intensity in this greater region are, hence, mainly governed by fluctuations in the balance between dust supply and moisture availability. Among the hitherto known sections, the Toshan loess-Soil sequence (LPS) represents a key site due to the quality of the record and the multitude of available data giving detailed insights into the timing and magnitude of dust accumulation and Soil Formation of the region. To elucidate these dynamics for much of the past 130.000 years bulk mineralogical and geochemical data are presented supplemented by a high resolution magnetic susceptibility record and by the results of a detailed micromorphological study of loess at Toshan. The last interglacial Luvisol/Phaeozem-like (∼MIS 5e) and the early glacial interstadial steppic palaeosols (∼MIS 5 c and a) are characterized by gradually increasing grain-size and decreasing degrees in decomposition of micaceous and mafic minerals. Pronounced feldspar weathering is detected in the last interglacial and modern Soils only, which formed under reduced or absent dust deposition on penultimate and last glacial loess, respectively (postsedimentary). The overall pedosedimentary conditions correspond to large scale trends of increasing drought, dust accumulation and wind strength in southern Eurasia in relation to decreasing moisture availability towards the early Pleniglacial (∼MIS 4), causing Soil Formation under ongoing dust deposition (synsedimentary). Similar intervals of synsedimentary Soil Formation are recorded during the interglacial/interstadial-stadial transitions of the early glacial and during pleniglacial (∼MIS 4 to 2) interstadials. The latter are marked by gradual increases in magnetic susceptibility, colour and decreasing texture. Conversely, silicate weathering could not be detected, suggesting that grain-size fluctuations are a primary feature. Thus, windy and arid pleniglacial conditions in southern Eurasia were interrupted by intermittent phases of synsedimentary Soil Formation, in response to short-lived and relatively moist interstadials. Although the interrelation of these incipient Soils, throughout southern Eurasia is afflicted with considerable restrictions, the oscillatory pattern of the Toshan LPS bears great similarity with millennial-scale oscillations recorded in limnic archives of western Asia.
Stefan Vlaminck - One of the best experts on this subject based on the ideXlab platform.
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late pleistocene dust dynamics and pedogenesis in southern eurasia detailed insights from the loess profile toshan ne iran
Quaternary Science Reviews, 2018Co-Authors: Stefan Vlaminck, Manfred Frechen, Eva Lehndorff, Martin Kehl, Christian Rolf, Svenoliver Franz, Tobias Lauer, Farhad KhormaliAbstract:Abstract In southern Eurasia recurrent phases of aridization, dust source extension and enhanced Aeolian sedimentation alternated with moister intervals, promoting reduced deflation areas and dust accumulation in the context of late Pleistocene climate changes. Weathering and Soil forming intensity in this greater region are, hence, mainly governed by fluctuations in the balance between dust supply and moisture availability. Among the hitherto known sections, the Toshan loess-Soil sequence (LPS) represents a key site due to the quality of the record and the multitude of available data giving detailed insights into the timing and magnitude of dust accumulation and Soil Formation of the region. To elucidate these dynamics for much of the past 130.000 years bulk mineralogical and geochemical data are presented supplemented by a high resolution magnetic susceptibility record and by the results of a detailed micromorphological study of loess at Toshan. The last interglacial Luvisol/Phaeozem-like (∼MIS 5e) and the early glacial interstadial steppic palaeosols (∼MIS 5 c and a) are characterized by gradually increasing grain-size and decreasing degrees in decomposition of micaceous and mafic minerals. Pronounced feldspar weathering is detected in the last interglacial and modern Soils only, which formed under reduced or absent dust deposition on penultimate and last glacial loess, respectively (postsedimentary). The overall pedosedimentary conditions correspond to large scale trends of increasing drought, dust accumulation and wind strength in southern Eurasia in relation to decreasing moisture availability towards the early Pleniglacial (∼MIS 4), causing Soil Formation under ongoing dust deposition (synsedimentary). Similar intervals of synsedimentary Soil Formation are recorded during the interglacial/interstadial-stadial transitions of the early glacial and during pleniglacial (∼MIS 4 to 2) interstadials. The latter are marked by gradual increases in magnetic susceptibility, colour and decreasing texture. Conversely, silicate weathering could not be detected, suggesting that grain-size fluctuations are a primary feature. Thus, windy and arid pleniglacial conditions in southern Eurasia were interrupted by intermittent phases of synsedimentary Soil Formation, in response to short-lived and relatively moist interstadials. Although the interrelation of these incipient Soils, throughout southern Eurasia is afflicted with considerable restrictions, the oscillatory pattern of the Toshan LPS bears great similarity with millennial-scale oscillations recorded in limnic archives of western Asia.
