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M. Callisto et al.
5.8 Case Study of the Trophic Evolution of a
Reservoir Used to Supply the Citizens of
the Paraíba State in the Semiarid Region
of Brazil
5.8.1 Site Description
The water resources of the Paraíba State are distributed
throughout 11 watersheds (Fig. 5.8), which contain more
than 123 reservoirs. These reservoirs hold more than
15 million m
3
of water intended for use as the public supply and they provide a maximum storage capacity of nearly
43,906,773,462 m
3
. The 20 reservoirs evaluated in this study
are located between 6°48′ to 8°12′S and 38°33′ to 34°47′W
(Fig. 5.8) and are present in two different hydrographic basins. The Paraíba and Piranhas River basins are the largest
basins in the Paraíba State, and they represent the highest
potential for water accumulation (28 and 67 %, respectively).
The climate classification of the reservoirs is BSwh,
according to Koppen’s classification system, which describes
a semiarid hot climate with 7–9 dry months. The average
temperatures are between 28 and 33 °C and the precipitation
Fig. 5.6 Classification of sites according to the TSI index for the Vargem das Flores (VF), Ibirité (I), and Serra Azul (AS) reservoirs during 2008
and 2009