Relação entre a desertificação e um modelo hidrológico no alto curso do Rio Paraíba-PB

Abstract

Besides suffering with permanent marks such as climate variability and water scarcity, Brazilian northeast semi-arid region also suffers from the desertification process, a phenomenon due to climatic and anthropogenic effects, from the rigors related to rainfall to the standard of living and pressure of human populations. Therefore, this paper analyzed how this phenomenon interferes in the hydrological system of a hydrographic basin, based on Caraúbas’ fluviometric station. Using a previously calibrated model, a satisfactory applicability of the model was verified with parameters considered quite sensitive, which allowed to have the dimension of how fragile the environment is before the submission of changes. It was also observed that the changes caused in the parameters by the desertification process will tend to increase the flow of the hydrographic basin, however, the exposed soil along with the intense surface runoff, causes sediment loading, causing erosion and silting the watercourses. When silted, the reservoirs tend to enlarge their water mirrors, which will facilitate the loss of water by evaporation, compromising the supply of a population that already suffers from a water shortage. Finally, it was concluded that the phenomenon in question is rather capable of interfering with the parameters of the model, and that the evolution of its impacts can further distract the model from the reality of the basin, unbalancing it.