MONITORING AND MODELING OF HYDROLOGICAL PROCESSES IN THE SEMIARID REGION
OF BRAZIL: THE CARIRI EXPERIMENTAL BASINS
Abstract
Two experimental basins – the Cariri basins – were installed in a
typically semiarid region in the State of Paraíba, Brazil, for obtaining
reliable estimates of runoff and soil erosion in different scales to
evaluate the influence of the human activities and other factors over
the processes of runoff and erosion. In the first basin, located in the
municipality of Sumé, the field studies were carried out at three
different scales: four micro-basins with an area of around 0.5 ha; nine
standard Wischmeier-type erosion plots of 100 m2 and seven sample plots
of 1 m2. The experimental units had varied vegetal cover and management
and, except the sample plots, were subjected to natural rainfall events
only, and were monitored from 1982 to 1991. The total runoff and total
sediment yield were determined for each of the events of precipitation.
The installations of the second basin, in the near municipality of São
João do Cariri, were planned for the continuation of the studies
initiated at Sumé, and include erosion plots (100 m2), micro-basins, and
sub-basins, which are being monitored for runoff and sediment production
up to now. Among them, two nested micro-basins were monitored to detect
any scale effect at the micro-basin level. Nearly 600 events of natural
precipitation, that produced runoff in at least one of the experimental
units, have been registered. This bulk of data was utilised to evaluate
the influence of various factors, including cultivation practices. The
data collected so far has been successfully used to calibrate
hydrological models for plots and micro-basins. Parameters have been
tested by means of cross validations among micro-basins and sub-basins.
The data sets, in part, have been made available to researchers in
Brazil and now the updated data files are being made available to all
the researchers in hydro-sedimentology at:
https://doi.org/10.5281/zenodo.4044690