Next Article in Journal
Bacteria Removal from Stormwater Runoff Using Tree Filters: A Comparison of a Conventional and an Innovative System
Previous Article in Journal
Bayesian Theory Based Self-Adapting Real-Time Correction Model for Flood Forecasting
Article Menu

Export Article

Open AccessArticle
Water 2016, 8(3), 74;

Daily Freeze–Thaw Cycles Affect the Transport of Metals in Streams Affected by Acid Drainage

Departamento de Ingeniería Hidráulica y Ambiental, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Macul, 7820436, Santiago, Chile
Departamento de Ingeniería Química y Ambiental, Universidad Técnica Federico Santa María, Avenida Vicuña Mackenna 3939, San Joaquín, 8940897, Santiago, Chile
CEDEUS, Centro de Desarrollo Urbano Sustentable, El Comendador 1916, Providencia, 7520245, Santiago, Chile
CIGIDEN, Centro Nacional de Investigación para la Gestión Integrada de Desastres Naturales, Vicuña Mackenna 4860, Macul, 7820436, Santiago, Chile
Author to whom correspondence should be addressed.
Academic Editor: Athanasios Loukas
Received: 26 November 2015 / Revised: 2 February 2016 / Accepted: 14 February 2016 / Published: 26 February 2016


Stream flow rates with seasonal, daily, or hourly cycles due to freezing and thawing can control downstream chemical processes by changing the mixing ratio of reactive flows. The extent of these hydrologic-chemical interactions has not been fully realized yet. This work explored the link between daily freeze-thaw cycles and the fate and transport of metals at a model stream impacted by acid drainage. We characterized hydrological and physicochemical parameters at the confluence between the Caracarani River (pH ~8.6) and the Azufre River (pH < 2), in northern Chile. Hourly water depth, temperature, and electrical conductivity monitoring coupled with pH and turbidity measurements revealed that maximum flow rates from thawing of the Azufre River induced characteristic daily drops in pH and turbidity. Shifts in pH controlled the precipitation and dissolution of arsenic-rich iron and aluminum reactive phases. Thus freeze-thaw processes are critical at streams receiving acid drainage where iron and aluminum phases form and are likely to impact the fate and transport of toxic metals in the system. This work highlights the importance of assessing the hydrological controls on flows and mixing ratios when studying the chemical reactivity and fate of contaminants at systems affected by acid drainage. View Full-Text
Keywords: diurnal cycles; aluminum; iron; arsenic; Lluta River; freeze-thaw; turbidity diurnal cycles; aluminum; iron; arsenic; Lluta River; freeze-thaw; turbidity

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Guerra, P.; Simonson, K.; González, C.; Gironás, J.; Escauriaza, C.; Pizarro, G.; Bonilla, C.; Pasten, P. Daily Freeze–Thaw Cycles Affect the Transport of Metals in Streams Affected by Acid Drainage. Water 2016, 8, 74.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Water EISSN 2073-4441 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top