@article{fdi:010023201,
  title = {{C}rystal chemistry of suspended matter in a tropical hydrosystem, {N}yong basin ({C}ameroon, {A}frica)},
  author = {{O}livi{\'e}-{L}auquet, {G}. and {A}llard, {T}. and {B}ertaux, {J}acques and {M}uller, {J}ean-{P}ierre},
  editor = {},
  language = {{ENG}},
  abstract = {{S}uspended matter ({SM}) from the {N}yong basin ({C}ameroon, {A}frica), a tropical watershed, was collected by tangential flow ultrafiltration to separate particulate (greater than 0.45 microm) and colloidal (less than 0.45 microm ; greater than 20 k{D}a) fractions. {I}n this basin, two distinctive systems in a selected small catchment ({N}simi-{Z}o{\'e}t{\'e}l{\'e}) of the {N}yong river basin have been considered : (i) colourless water (groundwater and spring) with a low suspended load (less than 3 mg/l) and a low total organic carbon content ({TOC} less than 1 mg/l) and (ii) coloured water ({M}engong brook and {N}yong river), which is organic rich ({TOC} greater than 10 mg/l) and contains higher amounts of {SM} (10-20 mg/l) than the colourless water. {F}reeze-dried sample of {SM} have been analysed by {X}-ray diffraction ({XRD}), transmission electron microscopy ({TEM}), {F}ourier-transform infrared spectroscopy ({FTIR}), electron paramagnetic resonance spectroscopy ({EPR}), and visible diffuse reflectance spectroscopy ({DRS}). {C}olourless water mainly contains mineral phases, such as poorly ordered kaolinite, plus quartz and goethite in the particulate fraction, and euhedral kaolinite plus amorphous iron oxyhydroxides in the colloidal fraction. {I}n contrast, the {SM} in coloured water is mainly organic in nature. {T}he mineral phases in the particulate fraction are similar to those from clear water, but with additional phytoliths and diatom frustules composed of biogenic opal. {I}n the colloidal fraction, complexation of {F}e3+ and {M}n2+ with organic matter is evidenced by {EPR}, together with significant occurence of {F}e oxyhydroxides associated with organic matter. {T}he sites of {A}l, {S}i, {M}n in colloidal fractions derived from spectroscopic analyses are discussed with reference to chemical analyses performed by inductively coupled plasma mass spectrometry... ({D}'apr{\`e}s r{\'e}sum{\'e} d'auteur)},
  keywords = {{SEDIMENT} ; {MATIERE} {EN} {SUSPENSION} ; {ANALYSE} {CHIMIQUE} ; {COMPOSITION} {CHIMIQUE} ; {ANALYSE} {MINERALOGIQUE} ; {DIFFRACTION} {DES} {RX} ; {MICROSCOPIE} {ELECTRONIQUE} {A} {TRANSMISSION} ; {SPECTROMETRIE} {INFRAROUGE} ; {COLLOIDE} ; {MATIERE} {ORGANIQUE} {PARTICULEE} ; {ELEMENT} {CHIMIQUE} {MAJEUR} ; {ELEMENT} {EN} {TRACE} ; {CROUTE} {D}'{ALTERATION} ; {EROSION} ; {ETUDE} {REGIONALE} ; {ZONE} {TROPICALE} ; {CAMEROUN} ; {NYONG} {BASSIN} {VERSANT}},
  booktitle = {},
  journal = {{C}hemical {G}eology},
  volume = {170},
  numero = {1-4},
  pages = {113--131},
  ISSN = {0009-2541},
  year = {2000},
  DOI = {10.1016/{S}0009-2541(99)00244-2},
  URL = {https://www.documentation.ird.fr/hor/fdi:010023201},
}