@article{fdi:010074407,
  title = {{H}ydrological functioning of western {A}frican inland valleys explored with a critical zone model},
  author = {{H}ector, {B}asile and {C}ohard, {J}. {M}. and {S}{\'e}guis, {L}uc and {G}alle, {S}ylvie and {P}eugeot, {C}hristophe},
  editor = {},
  language = {{ENG}},
  abstract = {{I}nland valleys are seasonally waterlogged headwater wetlands, widespread across western {A}frica. {T}heir role in the hydrological cycle in the humid, hard-rock-dominated {S}udanian savanna is not yet well understood. {T}hus, while in the region recurrent floods are a major issue, and hydropower has been recognized as an important development pathway, the scientific community lacks precise knowledge of streamflow ({Q}) generation processes and how they could be affected by the presence of inland valleys. {F}urthermore, inland valleys carry an important agronomic potential, and with the strong demographic rates of the region, they are highly subject to undergoing land cover changes. {W}e address both the questions of the hydrological functioning of inland valleys in the {S}udanian savanna of western {A}frica and the impact of land cover changes on these systems through deterministic sensitivity experiments using a physically based critical zone model ({P}ar{F}low-{CLM}) applied to a virtual generic catchment which comprises an inland valley. {M}odel forcings are based on 20 years of data from the {AMMA}-{CATCH} observation service and parameters are evaluated against multiple field data ({Q}, evapotranspiration - {ET} -, soil moisture, water table levels, and water storage) acquired on a pilot elementary catchment. {T}he hydrological model applied to the conceptual lithological/pedological model proposed in this study reproduces the main behaviours observed, which allowed those virtual experiments to be conducted. {W}e found that yearly water budgets were highly sensitive to the vegetation distribution: average yearly {ET} for a tree-covered catchment (944 mm) exceeds that of herbaceous cover (791 mm) {ET} differences between the two covers vary between 12 % and 24 % of the precipitation of the year for the wettest and driest years, respectively. {C}onsequently, the tree-covered catchment produces a yearly {Q} amount of 28 % lower on average as compared to a herbaceous-covered catchment, ranging from 20 % for the wettest year to 47 % for a dry year. {T}rees also buffer interannual variability in {ET} by 26 % (with respect to herbaceous). {O}n the other hand, pedological features (presence - or absence - of the low-permeability layer commonly found below inland valleys, upstream and lateral contributive areas) had limited impact on yearly water budgets but marked consequences for intraseasonal hydrological processes (sustained/non-sustained baseflow in the dry season, catchment water storage redistribution). {T}herefore, subsurface features and vegetation cover of inland valleys have potentially significant impacts on downstream water-dependent ecosystems and water uses as hydropower generation, and should focus our attention.},
  keywords = {{BENIN} ; {ZONE} {SOUDANOSAHELIENNE}},
  booktitle = {},
  journal = {{H}ydrology and {E}arth {S}ystem {S}ciences},
  volume = {22},
  numero = {11},
  pages = {5867--5900},
  ISSN = {1027-5606},
  year = {2018},
  DOI = {10.5194/hess-22-5867-2018},
  URL = {https://www.documentation.ird.fr/hor/fdi:010074407},
}