2025-12-012025-12-012025-11-05COSTA, José Ailton da Paixão. Qualidade da água do Rio Cereja, Bragança-Pará. Orientadora: Luci Cajueiro Carneiro Pereira. 2025. 42 f. Trabalho de Curso (Licenciatura em Ciências Naturais) – Faculdade de Ciências Naturais. Instituto de Estudos Costeiros, Campus Universitário de Bragança, Universidade Federal do Pará, Bragança-PA, 2025. Disponível em: https://bdm.ufpa.br/handle/prefix/8910. Acesso em: .https://bdm.ufpa.br/handle/prefix/8910The Cereja River, located in the municipality of Bragança-PA, is a Permanent Preservation Area (APP) with approximately 4 km of extension. The quality of its waters has been compromised by the lack of basic sanitation and the disorderly occupation of its banks. This study aimed to assess the water quality along the river, from its source to its mouth, in order to understand the impact of anthropogenic activities on this ecosystem. Hydrological variables — such as temperature, pH, turbidity, chlorophyll-a, and dissolved oxygen — and microbiological variables — including enterococci, thermotolerant coliforms, and total coliforms — were analyzed at seven distinct points along the river. The analyses followed the parameters established by CONAMA Resolution No. 357/2005, which regulates the quality of Class 2 freshwater. The methodology involved collecting surface water samples in June, August, October, and December of 2022, as well as in March and July of 2023. In situ measurements of pH, temperature, and dissolved oxygen were taken using the AKSO-AK88 multiparameter device. Turbidity was measured with a CTD; chlorophyll-a was analyzed by spectrophotometry; enterococci were identified using the cellulose acetate membrane filtration technique; and coliform concentrations were determined using the multiple-tube fermentation technique. The results indicated that, among the sampling points studied, 99% of the dissolved oxygen concentrations and 29.26% of the pH values were below the standards required by CONAMA.The highest concentrations of chlorophyll-a and turbidity levels were observed at sampling stations located in more urbanized areas. All analyzed points presented typical enterococci colonies in the 1, 10, and 100 ml water samples. Overall, a high rate of contamination by total and thermotolerant coliforms was found throughout the river. Based on CONAMA’s criteria, it is concluded that all types of water use in the Cereja River are compromised due to the high concentrations of thermotolerant coliforms along its course. Given this scenario, it is urgent to implement the measures proposed in the municipal master plan to restore and preserve the river’s water quality.Acesso AbertoQualidade de águaColiformesRio CerejaWater qualityColiformsCereja RiverCNPQ::CIENCIAS EXATAS E DA TERRATrabalho de Curso - Graduação - MonografiaAttribution-NonCommercial-NoDerivs 3.0 Brazil