Avaliação do grau de trofia do açude gavião

Abstract

The eutrophication phenomenon is a process of enriching water reservoirs by nutrients, usually containing phosphorus and nitrogen, which gradually reduces the quality and availability of water, which is an aggravating factor in the Northeastern semi-arid state, where there is already intense water loss. Climate and geomorphology. The present work shows the results of the analyzes carried out on water samples from the Gavião dam, a reservoir that supplies the metropolitan region of Fortaleza, in five different coordinates, and three depth levels in the year of 2017. The concentrations of total nitrogen, total phosphorus, nitrate, nitrite, orthophosphate, ammoniacal nitrogen and chlorophyll in water samples, adopting the spectrophotometric methodologies proposed by APHA (2005). The results showed that, according to the resolution CONAMA 357, some concentrations were with values above the maximum allowed value; the N / P ratioshowedthattherewasalternationbetweenthelimitingnutrientandthatthetrophicdegreewasalwaysabove 60, conferring a terrible trophic level of the waters.