@inproceedings{fdi:010025636,
  title = {{T}ransport and behaviour of total mercury in the {A}mazon river at the confluence of black and white waters},
  author = {{M}aurice {B}ourgoin, {L}aurence and {Q}uemerais, {B}. and {G}uyot, {J}ean-{L}oup and {L}araque, {A}lain and {S}eyler, {P}atrick},
  editor = {},
  language = {{ENG}},
  abstract = {{T}his study describes the transport and speciation of mercury and the associated role of organic matter in these processes at the confluence of the {N}egro ('black waters') and {S}olimoes ('white waters') rivers which form the {A}mazon river. {T}he {N}egro presents the highest total {H}g content (11,6 to 18,2 ng 1-1) due to the extreme particulate {H}g concentration which reaches values (2074 ng g-1 at the surface) 10 to 20 times higher than these measured in other {A}mazon tributaries. {T}he total organic carbon analysed in the {N}egro consists primarily of particulate carbon (54.8%), while the dissolved organic carbon is composed mainly of humic compounds (50%), carriers for most of the metal ions transported in both rivers. {A}t the confluence of the {N}egro and {S}olimoes {R}ivers, we observe an abrupt decrease of the {H}g content. {I}sotopic mass balance showed that the mixing of waters was achieves 25 km downstream the confluence. {S}ixty km downstream, the flux of {H}g decreases to 73 kg d-1, which represents a net loss of 5 kg dissolved {H}g d-1 and 15 kg particulate {H}g d-1, assuming that the discharge was constant during the sampling survey and without significant input from other tributaries. {H}owever, the observed losses can be correlated to the distribution of the total suspended matter which is not conservative throughout the mixing zone and with the particulate and colloidal organic carbon; net loss of {POC} is also observed. {W}e suggest that these particulate losses occur during the flocculation of organic matter within the zone of rapidly changing physical and chemical conditions downstream of the confluence, and the deposition of these particles along the mixing zone favoured by a decreasing river discharge during the sampling survey. ({R}{\'e}sum{\'e} d'auteur)},
  keywords = {{MERCURE} ; {COURS} {D}'{EAU} ; {TRANSPORT} {SOLIDE} ; {CONTAMINATION} ; {POLLUTION} {DES} {EAUX} {CONTINENTALES} ; {MATIERE} {EN} {SUSPENSION} ; {GEOCHIMIE} ; {EXPLOITATION} {DU} {SOUS} {SOL} ; {AMAZONIE} ; {AMAZONE} {FLEUVE}},
  numero = {},
  pages = {8  multigr.},
  booktitle = {{M}anaus'99 : hydrological and geochemical processes in large scale river},
  year = {1999},
  URL = {https://www.documentation.ird.fr/hor/fdi:010025636},
}