Temporal analysis of the behavior of the physicochemical quality of Buenaventura Bay, Colombia

Abstract

Coastal areas are the place where the continent meets the sea and fresh water mixes with salt water, always remaining in a constant state of change. In order to monitor the physicochemical and microbiological quality of Buenaventura Bay as an analysis of the different urban pollutant contributions, integrated samples were taken at a vertical level for the case of coastal waters and horizontal for the case of riverside waters of the Dagua River. 3 samplings were carried out in the area of influence of the Dagua River up to more than 200 meters above the bay, both in low and high tides. In situ mea- surements of physicochemical variables such as temperature, conductivity, dissolved solids, salinity, suspended solids, turbidity, dissolved oxygen, % saturation, pH, and nutrients such as nitrate, nitrite, and phosphate were made at each point, using a DR 900 colorimeter and a multiparameter HQ 40d. Additionally, a principal component analysis was applied to evaluate the management trends of the data obtained in the samplings carried out during 2013, 2015, 2018 and 2020. The results obtained during the monitoring allow inferring an improvement in the quality of the coastal waters of Buenaventura, however this coastal area is influenced by pollutants that enter through the Dagua River, the different containers represented in domestic discharges and liquid discharges contributed by the human settlements near the area and others originated by the different productive, marine and ports that are exercised in the place.