Résumé
The research of ruptures on rainfall and discharge serial
data from 1950 to 1995 of three small catchments (from 2000 to
6000 km2) of the Central African Republic, at the boundary between Chad and
Congo basins, has shown a high spatial variability. The rupture observed in
1970 at the subcontinental scale, which started the drought period in West
and Central Africa, is observed only on the Northward basin, the driest.
Then it was difficult to compare the hydroclimatic periods from a basin to
another one. However, all the studied basins have shown a degradation of the
hydrological regime from the end of the 1980s onward, with a severe level
since the end of 1980s. The depletion coefficients have the same range for
the 3 studied basins than for the Ubangi River basin, widening the drought
impact.