Physicochemical characterization and metal content in water and sediments of affluents to a reservoir in the southeast Peruvian Andes

Garate-Quispe J.; Gonzales-Aliaga R.; Ibañez-Quispe V. · Tropical and Subtropical Agroecosystems (2025) · DOI: 10.56369/tsaes.6270

Resumen

Background: Water is an essential natural resource for the survival of living organisms on Earth. However, recently, both anthropogenic and natural activities have contaminated water bodies in the Andes with metals and other pollutants. Objective: To characterize the water physicochemical and to determine the concentration of metals in water and sediments, as well as the relationship between them, in the tributaries of a reservoir in the southeastern Peruvian Andes. Methodology: We selected 19 sampling points (affluents). Two types of samples were taken at each sampling point: (1) water samples were taken for physicochemical analysis and to find out the concentration of 15 metals; and (2) sediment samples were taken to find out the concentration of 16 metals. We used Spearman’s correlation coefficient to analyze the relationship between water physicochemical properties and metal concentrations in water and sediments. Results: For most of the metals (As, Ba, Be, Cd, Cu, Fe, Mn, Pb, Sb and Zn) analyzed in water, concentrations higher than the Peruvian environmental quality standards (EQS) were found. The pH was inversely related to aluminium, beryllium, chromium, copper, iron, manganese, nickel and zinc. Conductivity was directly related to aluminium, beryllium, copper, nickel, lead, uranium and zinc. On the other hand, only positive and significant correlations were found between the concentrations of arsenic, boron, cadmium, lead and antimony found in water and sediments. Implications: It is important to adequately assess, manage, and monitor water resources to ensure their quality for human consumption. This is because we found that the physicochemical characteristics and metal concentrations in water exceed EQS and may represent a risk to human health. Conclusion: The study demonstrates the existence of acid rock drainage in the studied affluents. In most of the tributaries, pH, dissolved oxygen, and most of the metals in the water exceeded the EQS. In addition, an interaction process was evidenced between the concentration of metals in water and sediments. Copyright © the authors. Work licensed under a CC-BY 4.0 License. https://creativecommons.org/licenses/by/4.0/

Instituciones: Universidad Nacional del Altiplano; Universidad Nacional Amazónica de Madre de Dios