Water quality dynamics in urban river of the semiarid region under anthropogenic pressure: a spatiotemporal analysis in the stretch of the municipality of Mossoró (Brazil)
Source: PubMed Central Open Access, NCBI / U.S. National Library of Medicine
Over the years, urban rivers have suffered from environmental degradation due to anthropogenic activities, becoming a public concern. Thus, the objective of this study was to evaluate the spatiotemporal evolution of water quality in the Apodi-Mossoró River, in the urban section of Mossoró-RN, during the dry and rainy seasons. To this end, the physical–chemical and microbiological attributes of water samples collected at six points along the urban stretch of the Apodi-Mossoró River were characterized. Using the water quality data, the Water Quality Index was calculated, and multivariate statistical analysis was performed. The Water Quality Index varied considerably. At the Genésio Dam, a more positive assessment was observed, with ratings ranging from excellent to good. However, the other points showed significant variations, especially the Barrocas Dam, which received all ratings. The attributes that most influenced the results were total Kjeldahl nitrogen, turbidity and biochemical oxygen demand. The river water showed a high salt content, resulting in a classification as brackish at all points evaluated for most of the year, except during the rainy season, when it was considered fresh. Abs1 Highlights The water quality of the Apodi-Mossoró River is directly influenced by climate and urbanization. The WQI varies from excellent to poor, covering all classifications according to CETESB parameters. During the rainy season, the water of the Apodi-Mossoró River changes from brack
Abstract
Over the years, urban rivers have suffered from environmental degradation due to anthropogenic activities, becoming a public concern. Thus, the objective of this study was to evaluate the spatiotemporal evolution of water quality in the Apodi-Mossoró River, in the urban section of Mossoró-RN, during the dry and rainy seasons. To this end, the physical–chemical and microbiological attributes of water samples collected at six points along the urban stretch of the Apodi-Mossoró River were characterized. Using the water quality data, the Water Quality Index was calculated, and multivariate statistical analysis was performed. The Water Quality Index varied considerably. At the Genésio Dam, a more positive assessment was observed, with ratings ranging from excellent to good. However, the other points showed significant variations, especially the Barrocas Dam, which received all ratings. The attributes that most influenced the results were total Kjeldahl nitrogen, turbidity and biochemical oxygen demand. The river water showed a high salt content, resulting in a classification as brackish at all points evaluated for most of the year, except during the rainy season, when it was considered fresh. Abs1 Highlights The water quality of the Apodi-Mossoró River is directly influenced by climate and urbanization. The WQI varies from excellent to poor, covering all classifications according to CETESB parameters. During the rainy season, the water of the Apodi-Mossoró River changes from brackish to fresh throughout the urban stretch of Mossoró. TKN, TURB, and BOD, are the most influential attributes in the WQI classification of the Apodi-Mossoró River. Water quality declines downstream due to anthropic activity and increased pollutants. bullet Par2 Graphical Abstract http://www.w3.org/1999/xlink anchor MO1 portrait 10661_2026_15476_Figa_HTML.jpg Par8 Abs2 highlights