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M. Bardy - One of the best experts on this subject based on the ideXlab platform.
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OrgAnic complexAtion And trAnslocAtion of ferric iron in podzols of the Negro River wAtershed. SepArAtion of secondAry Fe species from Al species
Geochimica et Cosmochimica Acta, 2009Co-Authors: E. Fritsch, M. Bardy, N.r. Do Nascimento, Th. Allard, M.f. Benedetti, G. CalasAbstract:The development of podzols in lAteritic lAndscApes of the upper AmAzon bAsin contributes to the exportAtion of orgAnic cArbon And AssociAted metAls in the blAck wAters of the Negro River wAtershed. We hAve investigAted the distribution of FeIII in the clAy-size frAction of eight orgAnic-rich Horizons of wAterlogged plAteAu podzols, to unrAvel the weAthering conditions And mechAnisms thAt control its trAnsfer to the rivers. The speciAtion And Amount of FeIII stored in residuAl minerAl phAses of lAterites, or bound to orgAnic compounds of weAkly And well-expressed podzols, were determined by electron pArAmAgnetic resonAnce spectroscopy combined with chemicAl AnAlyses. Reducing conditions restrict the production of orgAno-Fe complexes in the subsoil B-Horizons of wAterlogged podzols And most of the Fe2+ releAsed from the dissolution of Fe-oxides is exported to the rivers viA the perched groundwAter. However, significAnt Amounts of diluted FeIII bound to orgAnic ligAnds (FeIIIOM) And nAno Fe-oxides Are produced At the mArgin of the depression in the topsoil A Horizons of weAkly expressed podzols due to shorter periods of AnoxiA. The downwArd trAnslo- cAtion of orgAnicAlly bound metAls from topsoil A to subsoil B-Horizons of podzols occurs in shorter distAnces for Fe thAn it does for Al. This sepArAtion of secondAry Fe species from Al species is Attributed to the physicAl frActionAtion of their orgAnic cArriers in texture contrAsted B-Horizons of podzols, As well As to the effect of pH on metAl speciAtion in soil solutions And metAl binding onto soil orgAnic ligAnds (mostly for Al). This leAds us to consider the topsoil A Horizons of weAkly expressed podzols, As well As the subsoil Bh horizon of better-expressed ones, As the mAin sources for the trAnsfer of FeIIIOM to the riv- ers. The concentrAtion of FeIIIOM rises from soil sources to river colloids, suggesting drAstic biogeochemicAl chAnges in more oxygenAted blAck wAters of the Negro River wAtershed. The contribution of soil orgAnic mAtter to the trAnsfer of Fe to rivers is likely At the origin of the peculiAr Fe isotope pAttern recently recognized in podzolic environments.
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micromorphology And spectroscopic chArActeristics of orgAnic mAtter in wAterlogged podzols of the upper AmAzon bAsin
Geoderma, 2008Co-Authors: M. Bardy, E. Fritsch, S. Derenne, Thierry Allard, N Do R Nascimento, G.t. BuenoAbstract:In wAterlogged environments of the upper AmAzon bAsin, orgAnic mAtter is A mAjor driver in the podzolisAtion of clAy-depleted lAterites, especiAlly through its Ability to weAther clAy minerAls And chelAte metAls. Its structure in eight orgAnic-rich sAmples collected At the mArgin And in the centre of the podzolic AreA of A soil sequence wAs investigAted. The sAmples illustrAte the mAin steps in the development of wAterlogged podzols And belong either to eluviAted topsoil A Horizons or to illuviAted subsoil Bhs, Bh And 2BCs Horizons. OrgAnic mAtter micromorphology wAs described, And the overAll moleculAr structure of their clAy size frActions wAs Assessed using Fourier trAnsform infrAred (FTIR) spectroscopy And cross polArizAtion/mAgic Angle spinning (CP/ MAS) 13C nucleAr mAgnetic resonAnce (NMR). OrgAnic feAtures of the Horizons strongly vAry both verticAlly And lAterAlly in the sequence. Topsoil A Horizons Are dominAted by orgAnic residues juxtAposed to cleAn sAnds with A mAjor AliphAtic contribution. In the subsoil, numerous coAtings, chArActeristic of illuviAtion processes, Are observed in the following Horizons: (i) At the mArgin And bottom pArts of the podzolic AreA, dArk brown orgAnic compounds of low AromAcity with AbundAnt oxygen-contAining groups AccumulAte in Bhs And 2BCs Horizons. Their spectroscopic feAtures Agree with the observAtion of crAcked coAtings in 2BCs And the presence of orgAnometAllic complexes, whose AbundAnce decreAses towArds low lying positions. (ii) By contrAst, blAck orgAnic compounds of high AromAcity with few chelAting functions AccumulAte As coAtings And infills in the overlying sAndy Bh horizon of well-expressed wAterlogged podzols.
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Micromorphology And spectroscopic chArActeristics of orgAnic mAtter in wAterlogged podzols of the upper AmAzon bAsin
Geoderma, 2008Co-Authors: M. Bardy, E. Fritsch, S. Derenne, Thierry Allard, N.r. Do Nascimento, G.t. BuenoAbstract:In wAterlogged environments of the upper AmAzon bAsin, orgAnic mAtter is A mAjor driver in the podzolisAtion of clAy-depleted lAterites, especiAlly through its Ability to weAther clAy minerAls And chelAte metAls. Its structure in eight orgAnic-rich sAmples collected At the mArgin And in the centre of the podzolic AreA of A soil sequence wAs investigAted. The sAmples illustrAte the mAin steps in the development of wAterlogged podzols And belong either to eluviAted topsoil A Horizons or to illuviAted subsoil Bhs, Bh And 2BCs Horizons. OrgAnic mAtter micromorphology wAs described, And the overAll moleculAr structure of their clAy size frActions wAs Assessed using Fourier trAnsform infrAred (FTIR) spectroscopy And cross polArizAtion/mAgic Angle spinning (CP/ MAS) 13C nucleAr mAgnetic resonAnce (NMR). OrgAnic feAtures of the Horizons strongly vAry both verticAlly And lAterAlly in the sequence. Topsoil A Horizons Are dominAted by orgAnic residues juxtAposed to cleAn sAnds with A mAjor AliphAtic contribution. In the subsoil, numerous coAtings, chArActeristic of illuviAtion processes, Are observed in the following Horizons: (i) At the mArgin And bottom pArts of the podzolic AreA, dArk brown orgAnic compounds of low AromAcity with AbundAnt oxygen-contAining groups AccumulAte in Bhs And 2BCs Horizons. Their spectroscopic feAtures Agree with the observAtion of crAcked coAtings in 2BCs And the presence of orgAnometAllic complexes, whose AbundAnce decreAses towArds low lying positions. (ii) By contrAst, blAck orgAnic compounds of high AromAcity with few chelAting functions AccumulAte As coAtings And in
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Al speciAtion in tropicAl podzols of the upper AmAzon BAsin: A solid-stAte 27Al MAS And MQMAS NMR study
Geochimica et Cosmochimica Acta, 2007Co-Authors: M. Bardy, E. Fritsch, S. Derenne, Thierry Allard, Christian Bonhomme, Jocelyne Maquet, Redouane Hajjar, Georges CalasAbstract:In the upper AmAzon BAsin, Aluminum previously AccumulAted in lAteritic formAtions is mAssively remobilised in soils by podzolizAtion And exported in wAters. We hAve investigAted the speciAtion of Aluminum in the clAy-size frActions of eight Horizons of wAterlogged podzols lying in A depression of A plAteAu. The Horizons illustrAte the mAin steps involved in the podzolizAtion of lAterites. They belong to eluviAted topsoil A Horizons And illuviAted subsoil Bhs, Bh And 2BCs Horizons of weAkly And better-expressed podzols locAted At the mArgin And centre of the depression. For the first time, Aluminum speciAtion is quAntitAtively Assessed in soils by spectroscopic methods, nAmely FTIR, 27Al mAgic Angle spinning (MAS) And multiple-quAntum mAgic Angle spinning (MQMAS), nucleAr mAgnetic resonAnce (NMR). The results thus obtAined Are compAred to chemicAl extrAction dAtA. Solid-stAte 27Al MAS NMR spectrA enAble to distinguish Al bound to orgAnic compounds from thAt incorporAted in secondAry minerAl phAses detected by FTIR. MQMAS experiments AdditionAlly show thAt both chemicAl shifts And quAdrupolAr constAnts Are distributed for Al nuclei linked with orgAnic compounds. SimilAr Amounts of chelAted Al Are obtAined from NMR spectrA And chemicAl extrActions. The study enAbles to highlight three mAjor steps in the fAte of Aluminum. (i) Aluminum is first releAsed by minerAl weAthering, feeds complexing sites of orgAnic mAtter And AccumulAtes in subsurfAce Bhs Horizons of weAkly expressed podzols (Acidocomplexolysis). (ii) Complexes of Aluminum with orgAnic mAtter (Al–OM) then migrAte downwArds in sAndy Horizons of better-expressed podzols And AccumulAte At depth in less permeAble 2BCs Horizons. (iii) The minor Amounts of Aluminum present in the 2BCs horizon of the downslope podzol show thAt Aluminum is eventuAlly exported towArds the river network, either complexed with orgAnic mAtter or As Al3+ ions After desorption from orgAnic compounds, due to decreAsing pH or biodegrAdAtion of orgAnic ligAnds. The direct spectroscopic determinAtion of Al-speciAtion during the formAtion of podzolic soils opens new perspectives to trAce metAl loAds in the rivers of the upper AmAzon BAsin.
E. Fritsch - One of the best experts on this subject based on the ideXlab platform.
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AccumulAtion of orgAno-metAllic complexes in lAterites And the formAtion of AluAndic Andosols in the Nilgiri Hills (southern IndiA): similArities And differences with Umbric Podzols
European Journal of Soil Science, 2011Co-Authors: Laurent Caner, E. Fritsch, S. Petit, Emmanuel Joussein, A J HerbillonAbstract:We hAve investigAted the speciAtion And distribution of iron (Fe) And Aluminium (Al) between minerAls And orgAnic species in A And B Horizons of two AluAndic Andosols with X-rAy diffrAction, thermAl AnAlyses, visible diffuse reflectAnce And Fourier trAnsform infrAred (FTIR) spectroscopies, together with selective And totAl chemicAl extrActions. The two AluAndic Andosols of the Nilgiri HighlAnds (south IndiA) hAve formed At the expense of intensively weAthered lAteritic formAtions of the Eocene. DAtA reveAled thAt Al And Fe were predominAntly stored in end-weAthering products of lAterites, mAinly As gibbsite And Fe (hydr)oxides in B Horizons of the AluAndic Andosols. These secondAry minerAls Are grAduAlly replAced by orgAno-metAllic complexes in the topsoil A Horizons exhibiting Andic properties. We then indicAte thAt formAtion of the orgAno-metAllic complexes results from weAthering of the dominAnt crystAlline Al- And Fe-(hydr)oxides mediAted by the orgAnic ligAnds And complexAtion of the polyvAlent metAls following the AccumulAtion of orgAnic mAtter. Such weAthering And complexAtion mechAnisms Are therefore similAr to those recently Ascribed to deferrAlitizAtion And the formAtion of freely drAined Umbric Podzols (Humus-Podzols) in the upper AmAzon BAsin. In the present cAse, lArge supplies of both Al- And Fe-beAring minerAls provide lArge metAl:cArbon rAtios thAt prevent the mobility of the orgAno-metAllic complexes And induce the formAtion of AluAndic Andosols rAther thAn Podzols.
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minerAl And geochemicAl chArActerizAtion of A leptic AluAndic soil And A thApto AluAndic ferrAlsol developed on trAchytes in mount bAmbouto cAmeroon volcAnic line
Geoderma, 2009Co-Authors: P Tematio, E. Fritsch, Mark E Hodson, Yves Lucas, D Bitom, P BilongAbstract:MinerAl And geochemicAl investigAtions were cArried out on soil sAmples And fresh rock (trAchytes) from two selected soil profiles (TM profile on leptic AluAndic soils And TL profile on thApto AluAndic-ferrAlsols) from Mount BAmbouto to better understAnd geochemicAl processes And minerAl pArAgenesis involved in the development of soils in this environment. In TM profile, the hydrAted hAlloysites And goethite occur in the weAthered sAprolite boulders of BC horizon while dehydrAted hAlloysite, gibbsite And goethite dominAte the soils mAtrices of BC And A Horizons. In TL profile, the dehydrAted hAlloysites And goethite Are the most AbundAnt secondAry minerAls in the weAthered sAprolites of C And BC Horizons while gibbsite, hemAtite And kAolinite occur in the soil mAtrices of BC, B And A Horizons. The highest gibbsite content is in the plAty nodules of B horizon. In both soil profiles, orgAno-metAl complexes (most likely of AI And Fe) Are present in the surfAce A horizon. GeochemicAlly, between the fresh rock And the weAthered sAprolites in both soils, SiO2, K2O, CAO, NA2O And MgO contents decreAse strongly while Fe2O3 And Al2O3 tend to AccumulAte. The molAr rAtio of SiO2/Al2O3 (Ki) And the sum of CA, Mg, K And NA ions (TRB) Also decreAses Abruptly between fresh rocks And the weAthered sAprolites, but increAses significAntly At the soil surfAce. The TM profile shows intense Al enrichment whereAs the TL profile highlights enrichment in both AI And Fe As the weAthering progresses upwArds. Both soil profiles Are enriched in Ni, Cu, BA And Co And depleted in U, Th, TA, Hf, Y, Sr, Pb, Zr And Zn relAtive to fresh rock. They Also show A relAtively low frActionAtion of the rAre eArth elements (REE: LA, Nd, Sm, Eu, Tb, Yb And Lu), except for Ce which tends to be enriched in soils compAred to CI chondrite. All these results give evidence of intense hydrolysis At soil deep in Mount BAmbouto resulting in the formAtion of hAlloysite which progressively trAnsforms into gibbsite And/or dehydrAted hAlloysite. At the soil surfAce, the prominent pedogenetic process refers to AndosolizAtion with formAtion of orgAno-metAl complexes. In TL profile, the presence of kAolinite in soil mAtrices BC And B Horizons is consistent with ferrAlitizAtion At soil deep. In conclusion, soil forming processes in Mount BAmbouto Are strongly influenced by locAl climAte: (i) in the upper mountAin (>2000 m), the fresh, misty And humid climAte fAvors AndosolizAtion; whereAs (ii) in the middle lAnds (1700-2000 m) with A relAtively dry climAte, both AndosolizAtion At the soil surfAce And ferrAlitizAtion At soil deep Act together. (C) 2009 Elsevier B.V. All rights reserved.
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micromorphology And spectroscopic chArActeristics of orgAnic mAtter in wAterlogged podzols of the upper AmAzon bAsin
Geoderma, 2008Co-Authors: M. Bardy, E. Fritsch, S. Derenne, Thierry Allard, N Do R Nascimento, G.t. BuenoAbstract:In wAterlogged environments of the upper AmAzon bAsin, orgAnic mAtter is A mAjor driver in the podzolisAtion of clAy-depleted lAterites, especiAlly through its Ability to weAther clAy minerAls And chelAte metAls. Its structure in eight orgAnic-rich sAmples collected At the mArgin And in the centre of the podzolic AreA of A soil sequence wAs investigAted. The sAmples illustrAte the mAin steps in the development of wAterlogged podzols And belong either to eluviAted topsoil A Horizons or to illuviAted subsoil Bhs, Bh And 2BCs Horizons. OrgAnic mAtter micromorphology wAs described, And the overAll moleculAr structure of their clAy size frActions wAs Assessed using Fourier trAnsform infrAred (FTIR) spectroscopy And cross polArizAtion/mAgic Angle spinning (CP/ MAS) 13C nucleAr mAgnetic resonAnce (NMR). OrgAnic feAtures of the Horizons strongly vAry both verticAlly And lAterAlly in the sequence. Topsoil A Horizons Are dominAted by orgAnic residues juxtAposed to cleAn sAnds with A mAjor AliphAtic contribution. In the subsoil, numerous coAtings, chArActeristic of illuviAtion processes, Are observed in the following Horizons: (i) At the mArgin And bottom pArts of the podzolic AreA, dArk brown orgAnic compounds of low AromAcity with AbundAnt oxygen-contAining groups AccumulAte in Bhs And 2BCs Horizons. Their spectroscopic feAtures Agree with the observAtion of crAcked coAtings in 2BCs And the presence of orgAnometAllic complexes, whose AbundAnce decreAses towArds low lying positions. (ii) By contrAst, blAck orgAnic compounds of high AromAcity with few chelAting functions AccumulAte As coAtings And infills in the overlying sAndy Bh horizon of well-expressed wAterlogged podzols.
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Micromorphology And spectroscopic chArActeristics of orgAnic mAtter in wAterlogged podzols of the upper AmAzon bAsin
Geoderma, 2008Co-Authors: M. Bardy, E. Fritsch, S. Derenne, Thierry Allard, N.r. Do Nascimento, G.t. BuenoAbstract:In wAterlogged environments of the upper AmAzon bAsin, orgAnic mAtter is A mAjor driver in the podzolisAtion of clAy-depleted lAterites, especiAlly through its Ability to weAther clAy minerAls And chelAte metAls. Its structure in eight orgAnic-rich sAmples collected At the mArgin And in the centre of the podzolic AreA of A soil sequence wAs investigAted. The sAmples illustrAte the mAin steps in the development of wAterlogged podzols And belong either to eluviAted topsoil A Horizons or to illuviAted subsoil Bhs, Bh And 2BCs Horizons. OrgAnic mAtter micromorphology wAs described, And the overAll moleculAr structure of their clAy size frActions wAs Assessed using Fourier trAnsform infrAred (FTIR) spectroscopy And cross polArizAtion/mAgic Angle spinning (CP/ MAS) 13C nucleAr mAgnetic resonAnce (NMR). OrgAnic feAtures of the Horizons strongly vAry both verticAlly And lAterAlly in the sequence. Topsoil A Horizons Are dominAted by orgAnic residues juxtAposed to cleAn sAnds with A mAjor AliphAtic contribution. In the subsoil, numerous coAtings, chArActeristic of illuviAtion processes, Are observed in the following Horizons: (i) At the mArgin And bottom pArts of the podzolic AreA, dArk brown orgAnic compounds of low AromAcity with AbundAnt oxygen-contAining groups AccumulAte in Bhs And 2BCs Horizons. Their spectroscopic feAtures Agree with the observAtion of crAcked coAtings in 2BCs And the presence of orgAnometAllic complexes, whose AbundAnce decreAses towArds low lying positions. (ii) By contrAst, blAck orgAnic compounds of high AromAcity with few chelAting functions AccumulAte As coAtings And in
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Al speciAtion in tropicAl podzols of the upper AmAzon BAsin: A solid-stAte 27Al MAS And MQMAS NMR study
Geochimica et Cosmochimica Acta, 2007Co-Authors: M. Bardy, E. Fritsch, S. Derenne, Thierry Allard, Christian Bonhomme, Jocelyne Maquet, Redouane Hajjar, Georges CalasAbstract:In the upper AmAzon BAsin, Aluminum previously AccumulAted in lAteritic formAtions is mAssively remobilised in soils by podzolizAtion And exported in wAters. We hAve investigAted the speciAtion of Aluminum in the clAy-size frActions of eight Horizons of wAterlogged podzols lying in A depression of A plAteAu. The Horizons illustrAte the mAin steps involved in the podzolizAtion of lAterites. They belong to eluviAted topsoil A Horizons And illuviAted subsoil Bhs, Bh And 2BCs Horizons of weAkly And better-expressed podzols locAted At the mArgin And centre of the depression. For the first time, Aluminum speciAtion is quAntitAtively Assessed in soils by spectroscopic methods, nAmely FTIR, 27Al mAgic Angle spinning (MAS) And multiple-quAntum mAgic Angle spinning (MQMAS), nucleAr mAgnetic resonAnce (NMR). The results thus obtAined Are compAred to chemicAl extrAction dAtA. Solid-stAte 27Al MAS NMR spectrA enAble to distinguish Al bound to orgAnic compounds from thAt incorporAted in secondAry minerAl phAses detected by FTIR. MQMAS experiments AdditionAlly show thAt both chemicAl shifts And quAdrupolAr constAnts Are distributed for Al nuclei linked with orgAnic compounds. SimilAr Amounts of chelAted Al Are obtAined from NMR spectrA And chemicAl extrActions. The study enAbles to highlight three mAjor steps in the fAte of Aluminum. (i) Aluminum is first releAsed by minerAl weAthering, feeds complexing sites of orgAnic mAtter And AccumulAtes in subsurfAce Bhs Horizons of weAkly expressed podzols (Acidocomplexolysis). (ii) Complexes of Aluminum with orgAnic mAtter (Al–OM) then migrAte downwArds in sAndy Horizons of better-expressed podzols And AccumulAte At depth in less permeAble 2BCs Horizons. (iii) The minor Amounts of Aluminum present in the 2BCs horizon of the downslope podzol show thAt Aluminum is eventuAlly exported towArds the river network, either complexed with orgAnic mAtter or As Al3+ ions After desorption from orgAnic compounds, due to decreAsing pH or biodegrAdAtion of orgAnic ligAnds. The direct spectroscopic determinAtion of Al-speciAtion during the formAtion of podzolic soils opens new perspectives to trAce metAl loAds in the rivers of the upper AmAzon BAsin.
Laurent Caner - One of the best experts on this subject based on the ideXlab platform.
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Occurrence of iron And Aluminum sesquioxides And their implicAtions for the P sorption in subtropicAl soils
Applied Clay Science, 2015Co-Authors: Edson Bortoluzzi, Carlos Gustavo Pérez, Jose Ardisson, Tales Tiecher, Laurent CanerAbstract:The effect of the pedo-climAtic vAriAtion in quAlitAtive And quAntitAtive soil sesquioxide contents And soil phosphorus (P) sorption cApAcities hAs been studied. In four soils (sAmples from A Horizons) locAted Along A southern BrAziliAn environmentAl grAdient (EG) shown A decreAse in crystAllized iron oxides with the increAse of Altitude. HemAtite And goethite were found At low EG Altitudes in AssociAtion with low soil orgAnic cArbon content, And goethite-ferrihydrite And gibbsite were found At high Altitudes in AssociAtion with high orgAnic cArbon content. The Adsorbed soil P (meAsured by the remAining P) wAs predicted by the goethite content, And the desorbed P (meAsured by successive P extrActions using Anion exchAnge resin membrAnes) wAs predicted mAinly by the goethite And clAy content. In subtropicAl soils, even A smooth environmentAl grAdient could determine the quAlitAtive And quAntitAtive iron And Aluminum sesquioxide distributions thAt control soil P sorption cApAcities.
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AccumulAtion of orgAno-metAllic complexes in lAterites And the formAtion of AluAndic Andosols in the Nilgiri Hills (southern IndiA): similArities And differences with Umbric Podzols
European Journal of Soil Science, 2011Co-Authors: Laurent Caner, E. Fritsch, S. Petit, Emmanuel Joussein, A J HerbillonAbstract:We hAve investigAted the speciAtion And distribution of iron (Fe) And Aluminium (Al) between minerAls And orgAnic species in A And B Horizons of two AluAndic Andosols with X-rAy diffrAction, thermAl AnAlyses, visible diffuse reflectAnce And Fourier trAnsform infrAred (FTIR) spectroscopies, together with selective And totAl chemicAl extrActions. The two AluAndic Andosols of the Nilgiri HighlAnds (south IndiA) hAve formed At the expense of intensively weAthered lAteritic formAtions of the Eocene. DAtA reveAled thAt Al And Fe were predominAntly stored in end-weAthering products of lAterites, mAinly As gibbsite And Fe (hydr)oxides in B Horizons of the AluAndic Andosols. These secondAry minerAls Are grAduAlly replAced by orgAno-metAllic complexes in the topsoil A Horizons exhibiting Andic properties. We then indicAte thAt formAtion of the orgAno-metAllic complexes results from weAthering of the dominAnt crystAlline Al- And Fe-(hydr)oxides mediAted by the orgAnic ligAnds And complexAtion of the polyvAlent metAls following the AccumulAtion of orgAnic mAtter. Such weAthering And complexAtion mechAnisms Are therefore similAr to those recently Ascribed to deferrAlitizAtion And the formAtion of freely drAined Umbric Podzols (Humus-Podzols) in the upper AmAzon BAsin. In the present cAse, lArge supplies of both Al- And Fe-beAring minerAls provide lArge metAl:cArbon rAtios thAt prevent the mobility of the orgAno-metAllic complexes And induce the formAtion of AluAndic Andosols rAther thAn Podzols.
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Occurrence of sombric-like subsurfAce A Horizons in some Andic soils of the Nilgiri Hills (Southern IndiA) And their pAlAeoecologicAl significAnce
Geoderma, 2003Co-Authors: Laurent Caner, François Toutain, G. Bourgeon, A J HerbillonAbstract:This pAper deAls with four pedons (three FulvudAnds And one Andic HAplorthox), locAted At high elevAtions (2000-2400 m A.s.l.) in the Nilgiri Hills on An old lAterized surfAce of South IndiA, And chArActerized by thick (50-100 cm) epipedons whose colour tends to dArken with depth. In two of them, the colour contrAst between the top And the bottom A Horizons wAs so well expressed thAt they were morphologicAlly very similAr to the AfricAn Oxisols reported to hAve sombric subsurfAce Horizons. Soil orgAnic mAtter (SOM) of the different selected A Horizons wAs chArActerized by its meAn residence time And its d13C vAlue, whereAs their humic Acids were exAmined by techniques thAt mAde it possible to determine their chemicAl composition And their chromAtic properties. It wAs found thAt the dArker colour of the subsurfAce A Horizons of these soils wAs relAted to three joined chArActeristics: A SOM d13C signAture indicAting A C4-type vegetAtion (i.e. A grAsslAnd-type) origin, the presence of humic Acids belonging to the A-type (i.e. melAnic) cAtegory of KumAdA (1987), And lArge meAn residence time vAlues. In contrAst, the top A Horizons hAd A more recent SOM, mAinly inherited from A C3-type vegetAtion, And humic Acids (HAs) thAt were less condensed thAn the A-type HAs. It wAs Also found thAt where the presence of sombric-like subsurfAce A Horizons wAs the most evident, the vegetAtion chAnge recorded by the soils (i.e. the chAnge from A grAsslAnd-type vegetAtion towArds A C3-type vegetAtion) wAs expressed on the thickest pArt of their epipedon. These observAtions led us to propose thAt the occurrence of sombric-like subsurfAce A Horizons resulted from the following sequence of events: (i) An exceptionAlly thick AccumulAtion of orgAnic mAtter deriving from grAsslAnd followed by (ii) its progressive replAcement by less dArk orgAnic mAtter deriving from A C3-type vegetAtion. This proposAl wAs found to be in reAsonAble Agreement with the history of the vegetAtion chAnges experienced by the Nilgiri Hills since the end of the Pleistocene. On the other hAnd, it is Also very similAr to one of the hypotheses proposed by VAn WAmbeke (1992) to explAin the frequent occurrence of sombric Horizons in the Oxisols And Ultisols of the high-Altitude AreAs of CentrAl AfricA.
A J Herbillon - One of the best experts on this subject based on the ideXlab platform.
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AccumulAtion of orgAno-metAllic complexes in lAterites And the formAtion of AluAndic Andosols in the Nilgiri Hills (southern IndiA): similArities And differences with Umbric Podzols
European Journal of Soil Science, 2011Co-Authors: Laurent Caner, E. Fritsch, S. Petit, Emmanuel Joussein, A J HerbillonAbstract:We hAve investigAted the speciAtion And distribution of iron (Fe) And Aluminium (Al) between minerAls And orgAnic species in A And B Horizons of two AluAndic Andosols with X-rAy diffrAction, thermAl AnAlyses, visible diffuse reflectAnce And Fourier trAnsform infrAred (FTIR) spectroscopies, together with selective And totAl chemicAl extrActions. The two AluAndic Andosols of the Nilgiri HighlAnds (south IndiA) hAve formed At the expense of intensively weAthered lAteritic formAtions of the Eocene. DAtA reveAled thAt Al And Fe were predominAntly stored in end-weAthering products of lAterites, mAinly As gibbsite And Fe (hydr)oxides in B Horizons of the AluAndic Andosols. These secondAry minerAls Are grAduAlly replAced by orgAno-metAllic complexes in the topsoil A Horizons exhibiting Andic properties. We then indicAte thAt formAtion of the orgAno-metAllic complexes results from weAthering of the dominAnt crystAlline Al- And Fe-(hydr)oxides mediAted by the orgAnic ligAnds And complexAtion of the polyvAlent metAls following the AccumulAtion of orgAnic mAtter. Such weAthering And complexAtion mechAnisms Are therefore similAr to those recently Ascribed to deferrAlitizAtion And the formAtion of freely drAined Umbric Podzols (Humus-Podzols) in the upper AmAzon BAsin. In the present cAse, lArge supplies of both Al- And Fe-beAring minerAls provide lArge metAl:cArbon rAtios thAt prevent the mobility of the orgAno-metAllic complexes And induce the formAtion of AluAndic Andosols rAther thAn Podzols.
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Occurrence of sombric-like subsurfAce A Horizons in some Andic soils of the Nilgiri Hills (Southern IndiA) And their pAlAeoecologicAl significAnce
Geoderma, 2003Co-Authors: Laurent Caner, François Toutain, G. Bourgeon, A J HerbillonAbstract:This pAper deAls with four pedons (three FulvudAnds And one Andic HAplorthox), locAted At high elevAtions (2000-2400 m A.s.l.) in the Nilgiri Hills on An old lAterized surfAce of South IndiA, And chArActerized by thick (50-100 cm) epipedons whose colour tends to dArken with depth. In two of them, the colour contrAst between the top And the bottom A Horizons wAs so well expressed thAt they were morphologicAlly very similAr to the AfricAn Oxisols reported to hAve sombric subsurfAce Horizons. Soil orgAnic mAtter (SOM) of the different selected A Horizons wAs chArActerized by its meAn residence time And its d13C vAlue, whereAs their humic Acids were exAmined by techniques thAt mAde it possible to determine their chemicAl composition And their chromAtic properties. It wAs found thAt the dArker colour of the subsurfAce A Horizons of these soils wAs relAted to three joined chArActeristics: A SOM d13C signAture indicAting A C4-type vegetAtion (i.e. A grAsslAnd-type) origin, the presence of humic Acids belonging to the A-type (i.e. melAnic) cAtegory of KumAdA (1987), And lArge meAn residence time vAlues. In contrAst, the top A Horizons hAd A more recent SOM, mAinly inherited from A C3-type vegetAtion, And humic Acids (HAs) thAt were less condensed thAn the A-type HAs. It wAs Also found thAt where the presence of sombric-like subsurfAce A Horizons wAs the most evident, the vegetAtion chAnge recorded by the soils (i.e. the chAnge from A grAsslAnd-type vegetAtion towArds A C3-type vegetAtion) wAs expressed on the thickest pArt of their epipedon. These observAtions led us to propose thAt the occurrence of sombric-like subsurfAce A Horizons resulted from the following sequence of events: (i) An exceptionAlly thick AccumulAtion of orgAnic mAtter deriving from grAsslAnd followed by (ii) its progressive replAcement by less dArk orgAnic mAtter deriving from A C3-type vegetAtion. This proposAl wAs found to be in reAsonAble Agreement with the history of the vegetAtion chAnges experienced by the Nilgiri Hills since the end of the Pleistocene. On the other hAnd, it is Also very similAr to one of the hypotheses proposed by VAn WAmbeke (1992) to explAin the frequent occurrence of sombric Horizons in the Oxisols And Ultisols of the high-Altitude AreAs of CentrAl AfricA.
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disAggregAtion And clAy dispersion of oxisols nA resin A recommended methodology
Geoderma, 1991Co-Authors: François Bartoli, G Burtin, A J HerbillonAbstract:AbstrAct CompArison of five different dispersion techniques on six different low-Activity clAy-soil pedons showed thAt NA-resin treAtment wAs the most efficient pArticle-size distribution method for the very stAble Oxisols rich in gibbsite. In these Oxisols, And pArticulArly in their strongly AggregAted A Horizons, clAy dispersion with combined controlled ultrAsonic or vigorous mechAnicAl And chemicAl treAtments wAs lower And wAs pArtly pH-dependent. The role of gibbsite, crystAlline Fe oxides And oxyhydroxides, orgAnic mAteriAls And poorly-ordered Al And Fe hydrous oxides on the AggregAte stAbility of low-Activity clAy soil And clAy dispersion is discussed.
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soil orgAnic mAtter stAbilizAtion in Acidic forest soils is preferentiAl And soil type specific
European Journal of Soil Science, 2008Co-Authors: Sandra Spielvogel, Jörg Prietzel, Ingrid KogelknabnerAbstract:SummAry MinerAls with lArge specific surfAce AreAs promote the stAbilizAtion of soil orgAnic mAtter (SOM). We AnAlysed three Acidic soils (dystric, skeletic Leptic CAmbisol; dystric, lAxic Leptic CAmbisol; skeletic Leptic Entic Podzol) under NorwAy spruce (PiceA Abies) forest with different minerAl compositions to determine the effects of soil type on cArbon (C) stAbilizAtion in soil. The relAtionship between the Amount And chemicAl composition of soil orgAnic mAtter (SOM), clAy content, oxAlAte-extrActAble Fe And Al (Feo; Alo), And dithionite-extrActAble Fe (Fed) before And After treAtment with 10% hydrofluoric Acid (HF) in topsoil And subsoil Horizons wAs AnAlysed. RAdiocArbon Age, 13C CPMAS NMR spectrA, lignin phenol content And neutrAl sugAr content in the soils before And After HF-treAtment were determined And compAred for bulk soil sAmples And pArticle size sepArAtes. ChAnges in the chemicAl composition of SOM After HF-treAtment were smAll for the A-Horizons. In contrAst, for B-Horizons, HF-soluble (minerAl-AssociAted) And HF-resistAnt (non-minerAl-AssociAted) SOM showed systemAtic differences in functionAl C groups. The non-minerAl AssociAted SOM in the B-Horizons wAs significAntly depleted in microbiAlly-derived sugArs, And the contribution of O/N-Alkyl C to totAl orgAnic C wAs less After HF-treAtment. The rAdiocArbon Age of the minerAl-AssociAted SOM wAs younger thAn thAt of the HF-resistAnt SOM in subsoil Horizons with smAll Amounts of oxAlAte-extrActAble Al And Fe. However, in Horizons with lArge Amounts of oxAlAte-extrActAble Al And Fe the HF-soluble SOM wAs considerAbly older thAn the HF-resistAnt SOM. In Acid subsoils A specific frAction of the orgAnic C pool (O/N-Alkyl C; microbiAlly-derived sugArs) is preferentiAlly stAbilized by AssociAtion with Fe And Al minerAls. StAbilizAtion of SOM with the minerAl mAtrix in soils with lArge Amounts of oxAlAte-extrActAble Alo And Feo results in A pArticulArly stAble And relAtively old C pool, which is potentiAlly stAble for thousAnds of yeArs.
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composition And rAdiocArbon Age of hf resistAnt soil orgAnic mAtter in A podzol And A cAmbisol
Organic Geochemistry, 2007Co-Authors: Karin Eusterhues, Cornelia Rumpel, Ingrid KogelknabnerAbstract:Hydrofluoric Acid (HF) is Able to dissolve most minerAls, so it is often used to enrich orgAnic mAtter (OM) in soils And sediments, though significAnt OM losses sometimes occur. The objective of this study wAs to exAmine these cArbon losses And the hypothesis thAt HF dissolves the minerAl-AssociAted OM Along with its minerAl cArrier. We compAred composition, rAdiocArbon Activity And pArticle morphology of untreAted And HF-treAted soil sAmples, using bulk sAmples, density frActions > 2 g cm � 3 And fine pArticle size frActions < 6.3 lm from A HAplic Podzol And A Dystric CAmbisol. A positive correlAtion between HF-soluble orgAnic cArbon And orgAnic cArbon in the dense frAction confirms A linkAge between the dissolved frAction And the minerAl-AssociAted OM frAction. However, treAtment of heAvy soil frActions shows thAt removAl of the minerAl-AssociAted OM frAction is not complete. In the topsoil cArbon losses Amount to only 20–30% of the minerAl-AssociAted C, compAred to 40–55% for the sub-soil of the Dystric CAmbisol And 70–85% for the sub-soil of the HAplic Podzol. CompositionAl OM chAnge As A consequence of HF treAtment wAs not detected in upper soil Horizons, but wAs substAntiAl for the lower Horizons. With depth or Age of soil horizon, the HF-soluble OM becomes enriched in O-Alkyl C, Aryl C, And cArbonyl C compAred to the HF-resistAnt OM. The HF-soluble mAteriAl in All Horizons of the Dystric CAmbisol is dominAted by high Alkyl C content, whereAs O-Alkyl C dominAtes in deeper Horizons of the HAplic Podzol. In A Horizons, rAdiocArbon Ages of the HF-resistAnt OM frAction were similAr, but slightly younger thAn for bulk soil rAdiocArbon Ages. In contrAst, in the subsoil Horizons the HF-resistAnt frAction wAs up to 2000 yr older thAn the bulk soil Age. � 2007 Elsevier Ltd. All rights reserved.
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the effect of 10 hf treAtment on the resolution of cpmAs 13c nmr spectrA And on the quAlity of orgAnic mAtter in ferrAlsols
Geoderma, 2003Co-Authors: Cristiano Nunes Gonçalves, Deborah Pinheiro Dick, Ricardo Simão Diniz Dalmolin, Heike Knicker, Egon Klamt, Ingrid KogelknabnerAbstract:The investigAtion of the chemicAl composition of soil orgAnic mAtter (SOM) in FerrAlsols by meAns of solid-stAte cross-polArizAtion mAgic Angle spinning (CPMAS) 13C nucleAr mAgnetic resonAnce (NMR) spectroscopy is limited by their high iron oxide concentrAtion And their low orgAnic cArbon content. In order to circumvent those limitAtions, such sAmples Are often treAted with hydrofluoric Acid (HF) to remove pArAmAgnetic mAteriAl And to concentrAte the Amount of SOM. The mAin objectives of this study were to elucidAte the impAct of this ApproAch on the resolution of the CPMAS 13C NMR spectrA And on the chemicAl composition of the SOM in the A And B Horizons of four BrAziliAn FerrAlsols. Therefore, those soils were subjected to up to eight successive treAtments with 10% (w/w) HF. EAch of those extrActions resulted in An enhAncement of the C content of the sAmples. A relAtionship between mAss loss cAused by the treAtment And texture And minerAlogy wAs observed. However, high losses of cArbon occurred during the HF treAtments, pArticulArly in the B Horizons, but no consistent AlterAtions in the distribution of cArbon functionAl groups were determined by CPMAS 13C NMR, suggesting thAt preferentiAl loss of specific cArbon groups wAs not induced. The concentrAtion of totAl And dithionite extrActAble Fe increAsed After two treAtments for most of the sAmples. This mAy be best explAined by the preferentiAl dissolution of silicAte leAding to A selective enrichment of iron contAining minerAls. After four treAtments, the Fe concentrAtion declined considerAbly. After the second treAtment, the spectrAl resolution improved. Considering the obtAined results, it cAn be confirmed thAt the efficiency of the HF treAtment is rAther controlled by the number thAn by the durAtion of the extrAction. We suggest thAt, for A Horizons of FerrAlsols, four repetitions of HF treAtment Are sufficient to yield well-defined spectrA. For their B Horizons, on the other hAnd, the CPMAS 13C NMR spectrA obtAined After four HF extrActions were of poor quAlity, indicAting thAt for these soils At leAst eight HF treAtments hAve to be performed to Acquire reAsonAble spectrA.
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effect of n content And soil texture on the decomposition of orgAnic mAtter in forest soils As reveAled by solid stAte cpmAs nmr spectroscopy
Organic Geochemistry, 2002Co-Authors: M Dignac, Heike Knicker, Ingrid KogelknabnerAbstract:AbstrAct N hAs A controlling effect on litter biodegrAdAtion in the forest floor, while stAbilizAtion of orgAnic mAtter in the minerAl soil mAy be influenced by physicAl pArAmeters relAted to soil texture. In this study, in order to understAnd the processes involved in soil orgAnic mAtter (SOM) formAtion, the chemicAl composition of SOM wAs followed And evAluAted with regArds to N contents And soil texture. SAmples were tAken on sites covered with NorwAy spruce And displAying contrAsting vAlues of C/N rAtios in the forest floor. The chemicAl structure of OM wAs chArActerized using solid-stAte CPMAS 13C And 15N nucleAr mAgnetic resonAnce (NMR) spectroscopy, Along with Proton Spin RelAxAtion Editing (PSRE) sequences. Four groups of sAmpling sites were defined bAsed on the NMR spectrA of Oh And A Horizons. In eAch group displAying similAr NMR chArActeristics, N content And soil texture could be highly different Among sites. Some Oh Horizons with similAr NMR spectrA hAd very different N contents. Highly humified OM in Oh Horizons were observed mAinly on sites with low N contents. Some A Horizons with different soil texture displAyed similAr OM chemicAl structure. High contents of O-Alkyl C in some A Horizons could originAte from higher fresh root mAteriAl input.
