Avaliação da influência dos efluentes municipais na química do estuário dos Bons Sinais-Quelimane

Abstract

The present work was carried out in the district of Quelimane to investigate the influence of municipal effluents on the chemistry of the Goods Signs estuary.the he had a field trip, during low tide of the tide (07/24/2017) during the morning. The water samples were collected at three sampling stations, namely: Provincial Hospital, Emose and Alif Quimica, with 3 points being considered for each station P0 (within the drainage channel), P1 (at the border between the estuary and drainage channel) and P2 (within the estuary), at the site was measured the concentration of dissolved oxygen. The water samples were analyzed in the laboratory of the company FIPAG (Fund of investment and heritage for water supply) using a portable photometer reference DR900 used methods 388N-Ammonia free, 361 N-Nitrate HR AV of the DR 900 photometer manual and the BOD was determined five days after the incubation of the samples With the analysis made, it was observed that the waters of the Bons Sinais estuary are within the limits permissible for the use, and the highest concentrations of nutrients as well as total coliforms were observed at the P1 point of the sampling stations. the maximum ammonium concentrations at point P1 at the border between the drainage channel with estuary, which was 0.50 mg / l l in Alif-chemistry and the lowest concentration was 0.25 mg / l in the same station. The nitrate had the maximum concentration of 12.1 mg / l in the chemical alif and the minimum of 4.5 mg / L in the provincial hospital station the highest BOD value was observed when it reached the maximum concentration of 2.5 mg / l and the minimum of 0.2 mg/L.