@article{PAR00000286,
  title = {{O}rigin of microaggregates in soils with ferralic horizons},
  author = {{C}ooper, {M}. and {V}idal {T}orrado, {P}. and {C}haplot, {V}incent},
  editor = {},
  language = {{ENG}},
  abstract = {{M}icroaggregates that characterize ferralic soils have been hypothesized to have physical, geochemical and/or biological origins. {D}espite of many studies, the hierarchy between these processes that form microaggregates has seldom been reported. {T}he objective of this work was to study the genesis of microaggregates in a sequence of {F}erralic {N}itisols developed on {Q}uaternary red clayey sediments and diabase in {P}iracicaba ({SP}), {B}razil. {T}his issue was tackled by combining optical microscopy, image analysis, scanning electron microscopy and elemental iron quantifications by {X}-ray fluorescence. {M}icromorphological investigations showed three different types of microaggregates: (i) oval microaggregates with well sorted quartz grains in their interior; (ii) oval microaggregates without or with poorly sorted quartz grains in their interior; and (iii) dense polyedric microaggregates. {T}hese morphological evidences, together with the elemental iron determinations and scanning electron microscopy, revealed the contribution of more than one process for microaggregate formation: (i) the mechanical action of the mesofauna would form the first type of microaggregates (ii) geochemical and biological processes would form the second type and (iii) the fissuration of the soil matrix by expansion and compression processes would form the third type.},
  keywords = {{N}itisol ; soil genesis ; micromorphology ; scanning electron microscopy},
  booktitle = {},
  journal = {{S}cientia {A}gricola},
  volume = {62},
  numero = {3},
  pages = {256--263},
  ISSN = {0103-9016},
  year = {2005},
  DOI = {10.1590/{S}0103-90162005000300009},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00000286},
}