Effects of Seasonality on the Environmental Quality of the Itanhaém Estuary

• Published in: Thalassas : revista de ciencias del mar 2021-10, Vol.37 (2), p.745-756
• Main Authors: Cesar-Ribeiro, Caio, Rosa, Helena Costi
• Format: Article
• Language: English
• Subjects: Acute toxicity; Agriculture; Bottom water; Chemistry; Coastal Sciences; Contamination; Earth and Environmental Science; Earth Sciences; Effluents; Environmental quality; Estuaries; Estuarine dynamics; Fish & Wildlife Biology & Management; Fish populations; Fishers; Freshwater & Marine Ecology; Freshwater crustaceans; Household wastes; Livestock; Marine & Freshwater Sciences; Nutrients; Oceanography; Organic matter; Organic phosphorus; Phosphates; Phosphorus; Seasonal variations; Seasonality; Sediment; Sediment samples; Sediments; Sewage; Sewage treatment; Sewage treatment plants; Statistical methods; Tourism; Tourist activities; Toxicity testing; Toxicity tests; Wastewater treatment; Wastewater treatment plants; Water analysis; Water quality; Water sampling
• ISSN: 0212-5919; 2366-1674
• DOI: 10.1007/s41208-021-00329-w

This work evaluates the quality of Itanhaém Estuary water in Autumn; Winter, and Spring. In each station were collected samples of water and sediment, being collected subsurface, middle, and bottom water to analyze physical-chemistry, chemistry, and ecotoxicological parameters of the water and the concentration of the organic matter and Phosphorus in sediment. It was developed acute toxicity tests with bottom water using like an organism test the specie Daphnia similis. Through the statistical analyzes in the test-t of bioequivalence, it was possible to observe toxicity in the points near the sewage station and the agriculture activities sites. The chemistry analysis demonstrates more nutrients in the points near the sewage treatment plant (STP). Just the total Phosphorus and the phosphate showed concentration superior to the recommended good quality of the water. Human activities like agriculture, livestock, and the discharge of domestic effluents are slowly affecting the quality of the water and sediment in this estuary; this study demonstrates that the sample point near the STP during seasons (after vacation and Carnaval) when the tourism activities increase showed higher contamination of this ecosystem than the other sample points, so it is necessary to improve the treatments to preserve this environment that it is so essential to the fishers and the population.