@article{fdi:010066988,
  title = {{A}mazon {R}iver dissolved load : temporal dynamics and annual budget from the {A}ndes to the ocean},
  author = {{M}oquet, {J}. {S}. and {G}uyot, {J}ean-{L}oup and {C}rave, {A}. and {V}iers, {J}. and {F}ilizola, {N}. and {M}artinez, {J}ean-{M}ichel and {O}liveira, {T}. {C}. and {S}anchez, {L}. {S}. {H}. and {L}agane, {C}hristelle and {C}asimiro, {W}. {S}. {L}. and {N}oriega, {L}. and {P}ombosa, {R}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he aim of the present study is to estimate the export fluxes of major dissolved species at the scale of the {A}mazon basin, to identify the main parameters controlling their spatial distribution and to identify the role of discharge variability in the variability of the total dissolved solid ({TDS}) flux through the hydrological cycle. {D}ata are compiled from the monthly hydrochemistry and daily discharge database of the "{P}rograma {C}limatologico y {H}idrologico de la {C}uenca {A}mazonica de {B}olivia" ({PHICAB}) and the {HYBAM} observatories from 34 stations distributed over the {A}mazon basin (for the 1983-1992 and 2000-2012 periods, respectively). {T}his paper consists of a first global observation of the fluxes and temporal dynamics of each geomorphological domain of the {A}mazon basin. {B}ased on mean interannual monthly flux calculations, we estimated that the {A}mazon basin delivered approximately 272 x 10(6) t year(-1) (263-278) of {TDS} during the 2003-2012 period, which represents approximately 7 % of the continental inputs to the oceans. {T}his flux is mainly made up by {HCO}3, {C}a and {S}i{O}2, reflecting the preferential contributions of carbonate and silicate chemical weathering to the {A}mazon {R}iver {B}asin. {T}he main tributaries contributing to the {TDS} flux are the {M}araon and {U}cayali {R}ivers (approximately 50 % of the {TDS} production over 14 % of the {A}mazon basin area) due to the weathering of carbonates and evaporites drained by their {A}ndean tributaries. {A}n {A}ndes-sedimentary area-shield {TDS} flux (and specific flux) gradient is observed throughout the basin and is first explained by the {TDS} concentration contrast between these domains, rather than variability in runoff. {T}his observation highlights that, under tropical context, the weathering flux repartition is primarily controlled by the geomorphological/geological setting and confirms that sedimentary areas are currently active in terms of the production of dissolved load. {T}he log relationships of concentration vs discharge have been characterized over all the studied stations and for all elements. {T}he analysis of the slope of the relationship within the selected contexts reveals that the variability in {TDS} flux is mainly controlled by the discharge variability throughout the hydrological year. {A}t the outlet of the basin, a clockwise hysteresis is observed for {TDS} concentration and is mainly controlled by {C}a and {HCO}3 hysteresis, highlighting the need for a sampling strategy with a monthly frequency to accurately determine the {TDS} fluxes of the basin. {T}he evaporite dissolution flux tends to be constant, whereas dissolved load fluxes released from other sources (silicate weathering, carbonate weathering, biological and/or atmospheric inputs) are mainly driven by variability in discharge. {T}hese results suggest that past and further climate variability had or will have a direct impact on the variability of dissolved fluxes in the {A}mazon. {F}urther studies need to be performed to better understand the processes controlling the dynamics of weathering fluxes and their applicability to present-day concentration-discharge relationships at longer timescales.},
  keywords = {{A}mazon basin ; {A}ndes ; {S}edimentary areas ; {L}arge rivers ; {W}ater chemistry ; {D}issolved solid flux ; {W}eathering ; {H}ydrological variability ; {BRESIL} ; {PEROU} ; {BOLIVIE} ; {COLOMBIE} ; {EQUATEUR} ; {ANDES} ; {AMAZONE} {BASSIN}},
  booktitle = {},
  journal = {{E}nvironmental {S}cience and {P}ollution {R}esearch},
  volume = {23},
  numero = {12},
  pages = {11405--11429},
  ISSN = {0944-1344},
  year = {2016},
  DOI = {10.1007/s11356-015-5503-6},
  URL = {https://www.documentation.ird.fr/hor/fdi:010066988},
}