Transport,distribution, and the fate of emerging contaminants in wastewater-receiving rivers under multiple stress conditions
- Autores: Ladislav Mandaric
- Directores de la Tesis: Sergi Sabater i Cortés (dir. tes.), Mira Petrovic (codir. tes.)
- Lectura: En la Universitat de Girona ( España ) en 2018
- Idioma: español
- Tribunal Calificador de la Tesis: Isabel Muñoz Gràcia (presid.), María José López de Alda Villaizán (secret.), Dimitroula Lambropoulou (voc.)
- Programa de doctorado: Programa de Doctorado en Ciencia y Tecnología del Agua por la Universidad de Girona
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
The pharmaceutically active compounds (PhACs) are amongst the emerging contaminants of anthropogenic origin with the most continuous input into the aquatic environment. Their continuous arrival makes them pseudo-persistent contaminants, that is, being transformation and removal rates compensated by their continuous discharge into the environment. Once released to the aquatic environment, a number of processes govern their fate and transport. Biodegradation, abiotic oxidation, and hydrolysis, photolysis, adsorption/desorption, dissolution, volatilization, and dispersion are the most important in-stream attenuation processes involved. However, the relative importance of these processes depends on the rates at which they occur under natural environmental conditions. These rates are, in turn, dependent on the chemical structure and properties of the substance and its distribution in the various compartments of the environment. Therefore, understanding the transport, distribution, and fate of PhACs is a prerequisite for a thorough assessment of the risk they represent in wastewater-receiving rivers under multiple stress. Among multiple stressors in the Mediterranean aquatic environment, water scarcity has direct and indirect effects, on distribution and fate of the PhACs.
The main aim of this thesis was to establish a link between the urban origin of chemical contamination (e.g. PhACs) and other stressors, particularly associated to water scarcity (Chapter 1, 2 and 3). Research has been performed in one Alpine (Chapter 1) and two Mediterranean river basins (Chapter 2 and 3). Effects of the river flow variability on the recovery potential of the rivers (natural in-stream attenuation) have been studied in the tributary streams of the lower Ebro River (Chapter 2) and the Evrotas River (Chapter 3). Results have shown that occurrence and spatiotemporal distribution of PhACs in the fragile Alpine and Mediterranean aquatic environments is subjected to a strong intra-annual variability of the stream flow, while effects of multiple stress conditions may be amplified under water scarcity conditions (e.g. drought), thus resulting in the increased concentrations levels of PhACs in river water and sediments. Increased water travel time and simultaneously longer residence time of PhACs within the river stretch or waterbody during low flow conditions in the intermittent Mediterranean rivers and streams contributed considerably to the generally higher in-stream attenuation of PhACs.
