DINIZ, C. R.; http://lattes.cnpq.br/5852965121074357; DINIZ, Célia Regina.
Resumo:
Space/temporal and daily/vertical studies were fulfilled in two different dams with
different typologies. Located at Paraiba State (Epitacio Pessoa and Bodocongo). The
goals were to study the physical, chemical, biological and microbiological variations,
in the surface and in the backwater during annual and daily cycles (24 hours): to
identify the months, times and the most critical depths related to the water quality in
the dams; to evaluate the efficiency in the hydraulic basin areas including water
macrophyte, in the reduction of organic, inorganic and fecal pollutions during the long
period and to analyze the patterns of stratification and the mix in the distribution of
studied parameters. The quality of water showed variability on time and space, under
influence of climate, morphological and anthropogenic factors. In the Epitacio Pessoa
dam occurred variations in the quality on the shores were they were no more
accentuated during the rains. In the Bodocongo dam, the tributary drains had a big
influence in the water quality, helping the water homogeneity into the central point
and in the shores. The grouping analysis in the both dams was followed by an
associated instruction to the pollution/contamination levels. In the Epitacio Pessoa
dam was formed three groups with dissimilar characteristics of point's quality where a
group joined three points in the limnetic region of better water quality. Paraiba River
with intermediate quality and a third represented by the point of flowing from Taperoa
river, with the highest level of pollution, reflecting the human activities on its drainage
basin. In Bodocongo was formed two groupings: one who joined the points from the
shores and from the central and other that formed by the point of biggest impact
atrophic, next to the continuing flushers of drains. In the Epitacio Pessoa dam the
PCA extracted two main components, that accumulated 54% (rains) and 42%
(drought) form the system variant. In the rains the components who standed out
where: nutritious and suspended/cloudy solid and in the drought, the nutritious and
salty components. In the Bodocongo dam the PCA showed in the rains the solid
components associated with the cloudy and nutritious/sanitary state (40%) and in the
dry spell, the following components: salty and algal nutritious/biomass (37%). The
two dams showed daily patterns of stratification and mix that gave characteristics like
hot polimitcs influenced by win and depth. The thermos stratification occurred during
the illuminated times during the day and the mix predominated at night. The thermos
homogeneity during the night favored the mix of released nutrients from the sediment
increasing the amount in the water. The oxygen dissolved was more sensitive to the
thermos stratification and showed a clinograd profile on the two water objects. The
PCA applicated like nictemeral had like a source of more variability as temporal
variations (day/night). The typology, based in the Carlson Modified Index classified
the Epitacio Pessoa and Bodocongo dams as hipereutrophic. The water macrophytes
showed themselves efficient in the reduction of the polluted loads in the Bodocongo
dam, and with the appropriate handling, they can be ecological solutions in the
improvement of the water quality during the stratification process.