@article{fdi:010059001,
  title = {{U}nravelling zinc and lead distributions in dolomitic and metapelitic soils of the {B}razilian {C}entral {P}lateau : insight from physical fractionation, optical microscopy and {X}-ray microfluorescence},
  author = {{B}urak, {D}. {L}. and van {O}ort, {F}. and {B}ecquer, {T}hierry and {F}oy, {E}. and {F}ontes, {M}. {P}. {F}.},
  editor = {},
  language = {{ENG}},
  abstract = {{L}arge zinc and lead concentrations occur in strongly weathered soils of {C}ambisol{F}erralsol toposequences in the {P}aracatu-{V}azante area ({C}entral {P}lateau, {B}razil). {W}eathering of the mineralized dolomite parent material of the {C}ambisols is hypothesized to be the geogenic source of zinc ({Z}n) and lead ({P}b), with dissemination downslope into the {F}erralsols. {T}his leads to different metal distribution patterns in the two soils. {W}e studied {Z}n and {P}b distributions in selected {A} and {B} horizons of two typical profiles to examine this hypothesis and assess the contribution of sesquioxides to the retention of these metals. {P}hysical separation into 2002000, 50200, 2050 and < 20-mu m size fractions in water without chemical dispersants was carried out before ({F}1) and after ({F}2) ultrasonification. {T}he fractions were analysed for total and extractable {Z}n and {P}b concentrations and studied by {X}-ray diffraction and optical microscopy. {M}icroscale {Z}n and {P}b distribution maps were obtained by using micro-{X}-ray fluorescence on thin sections. {F}or the {C}ambisol, the composition, morphology and large {Z}n and {P}b concentrations of coarse-sized {F}2 fractions were consistent with a geogenic metal origin. {I}n both soils, < 20-mu m fractions contained the largest amounts of {Z}n and {P}b. {I}n the {C}ambisol, this < 20-mu m fraction included poorly crystalline {M}n-rich material, encouraging strong {P}b sorption. {T}he {F}erralsol < 20-mu m fractions contained more {A}l- and {F}e-oxide-rich microaggregates, which also enhanced strong metal retention. {L}arge sesquioxide contents in these and similar tropical soils reduce metal mobilities. {T}his limits the risk of toxicity when such soils, with metal contents exceeding guidelines, are used for agriculture.},
  keywords = {{BRESIL}},
  booktitle = {},
  journal = {{E}uropean {J}ournal of {S}oil {S}cience},
  volume = {64},
  numero = {1},
  pages = {131--144},
  ISSN = {1351-0754},
  year = {2013},
  DOI = {10.1111/ejss.12006},
  URL = {https://www.documentation.ird.fr/hor/fdi:010059001},
}