@article{fdi:010040818,
  title = {{S}uspended sediment transport in a semiarid watershed, {W}adi {A}bd, {A}lgeria (1973-1995)},
  author = {{A}chite, {M}. and {O}uillon, {S}ylvain},
  editor = {},
  language = {{ENG}},
  abstract = {{A} quantification of the fine sediment budget of a wadi (dryland river) in {NW} {A}lgeria is presented for a period of 22 hydrological years (1973-1995). {T}he climate is {M}editerranean over the {W}adi {A}bd basin (2480 km(2)), the mean annual precipitation is 250 mm and the mean annual discharge is 1.0 m(3) s(-1) at the gauging station. {R}egression relationships between water discharge {Q} and suspended sediment concentration {C} are calculated from 1432 paired measurements in the {W}adi {A}bd, leading to power-law equations of the type {C} = a {Q}(b). {T}he variability of coefficients a and b, calculated for 138 floods and flood stages, is analyzed. {T}he median value of b is 0.757, indicating that {C} is almost proportional to {Q}(3/4). {G}iven that the (a, b) pairs are correctly aligned (r(2) = 0.578), the coefficients a and b are not independent. {R}egression relationships between daily {Q} and daily suspended sediment concentration and discharge {Q}(s) are calculated from 702 input data. {T}he performances of these regression relationships are shown to be equivalent, leading to over-estimations of 20-25% of the suspended sediment flux. {T}he non-biased {C}-{Q} sediment rating curve is used to extrapolate a time series of {C} measurements, and thus to analyze the long-term patterns in suspended sediment transport. {A}verage sediment wash-down (136 t km(-2) yr(-1)) is similar to the mean global value. {T}he ratio of sediment wash-down to the river water discharge is 10.7 x 10(6) t km(3), 20 times greater than the average ratio in the {E}arth's eastern hemisphere, and illustrates the highly erosive power of wadis. {V}ariability is shown to be significant at the seasonal scale ({CV} = 89%) and higher at the interannual scale ({CV} = 139%). {T}he fine sediment flux mainly occurs in autumn (48.4%) and spring (32.7%). {A}lthough precipitation decreased, it was more irregular from one year to another over the period 1985-1995 than during the period 1973-1985, and the {W}adi {A}bd, which was a perennial river, became intermittent in the late 1980s. {T}his increasing irregularity is accompanied by: an amplification of the variations of discharge, an increase in the average discharge of approximately 20% during the second period, and a higher and more irregular suspended particulate flux. {T}he mean annual suspended sediment yield is shown to be highly correlated with the standard deviation of mean daily discharge calculated per year (r(2) = 0.989). {T}he highly significant interannual. variability points to the difficulty of defining a suitable period to calculate a reference value for sediment budgets. {I}t also emphasizes the absolute necessity of continuing a series of measurements over {L}onger time periods to study fluctuations in the context of climate change.},
  keywords = {water erosion ; suspended sediment concentration ; sediment transport ; rating curve ; {W}adi ; intermittent river ; {A}lgeria},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {343},
  numero = {3-4},
  pages = {187--202},
  ISSN = {0022-1694},
  year = {2007},
  DOI = {10.1016/j.jhydrol.2007.06.026},
  URL = {https://www.documentation.ird.fr/hor/fdi:010040818},
}