@article{fdi:010067587,
  title = {{H}ydrological, chemical, and isotopic budgets of {L}ake {C}had : a quantitative assessment of evaporation, transpiration and infiltration fluxes},
  author = {{B}ouchez, {C}. and {G}oncalves, {J}. and {D}eschamps, {P}ierre and {V}allet-{C}oulomb, {C}. and {H}amelin, {B}runo and {D}oumnang, {J}. {C}. and {S}ylvestre, {F}lorence},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n the {S}ahelian belt, {L}ake {C}had is a key water body for 13 million people, who live on its resources. {I}t experiences, however, substantial and frequent surface changes. {L}ocated at the centre of one of the largest endorheic basins in the world, its waters remain surprisingly fresh. {I}ts low salinity has been attributed to a low infiltration flow whose value remains poorly constrained. {U}nderstanding the lake's hydrological behaviour in response to climate variability requires a better constraint of the factors that control its water and chemical balance. {B}ased on the three-pool concep-tualization of {L}ake {C}had proposed by {B}ader et al. (2011), this study aims to quantify the total water outflow from the lake, the respective proportions of evaporation ({E}), transpiration ({T}), and infiltration ({I}), and the associated uncertainties. {A} {B}ayesian inversion method based on lake-level data was used, leading to total water loss estimates in each pool ({E} + {T} + {I} = {ETI}). {S}odium and stable isotope mass balances were then used to separate total water losses into {E}, {T}, and {I} components. {D}espite the scarcity of representative data available on the lake, the combination of these two geochemical tracers is relevant to assess the relative contribution of these three outflows involved in the control of the hydrological budget. {M}ean evapotranspiration rates were estimated at 2070 +/- 100 and 2270 +/- 100 mm yr(-1) for the southern and northern pools, respectively. {I}nfiltration represents between 100 and 300 mm yr(-1) but most of the water is evapotranspirated in the first few kilometres from the shorelines and does not efficiently recharge the {Q}uaternary aquifer. {T}ranspiration is shown to be significant, around 300 mm yr(-1) and reaches 500 mm yr(-1) in the vegetated zone of the archipelagos. {H}ydrological and chemical simulations reproduce the marked hydrological change between the normal lake state that occurred before 1972 and the small lake state after 1972 when the lake surface shrunk to a one-tenth of its size. {A}ccording to our model, shrinking phases are efficient periods for salt evacuation from the lake towards the phreatic aquifer.},
  keywords = {{TCHAD} ; {CAMEROUN} ; {NIGERIA} ; {NIGER} ; {CENTRAFRIQUE} ; {ZONE} {SAHELIENNE} ; {TCHAD} {LAC}},
  booktitle = {},
  journal = {{H}ydrology and {E}arth {S}ystem {S}ciences},
  volume = {20},
  numero = {4},
  pages = {1599--1619},
  ISSN = {1027-5606},
  year = {2016},
  DOI = {10.5194/hess-20-1599-2016},
  URL = {https://www.documentation.ird.fr/hor/fdi:010067587},
}