DUGi

Potencial de fitorremediación y tolerancia de especies vegetales ante compuestos persistentes, móviles y tóxicos en el tratamiento de aguas grises

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@10256@@28653

This study explores the potential of nature-based solutions (NBS), particularly green walls, for the treatment and reuse of synthetic greywater (SGW) contaminated with persistent, mobile, and toxic (PMT) pollutants. The research focuses on evaluating the phytoremediation capacity and tolerance of nine plant species commonly used in green walls. A hydroponic experimental setup was implemented using 16 PVC channels at the Catalan Institute for Water Research (ICRA), simulating green wall conditions. Each plant species was assessed for its effectiveness in removing eight PMT contaminants: Benzotriazole (BTH), Ditolylguanidine (DTG), Melamine (MEL), Metformin (MET), Phenazone (PHN), Tris(2-chloroethyl) phosphate (TCEP), Trifluoroacetic acid (TFA), and Perfluorobutyric acid (PFBA). The experimental design involved two successive cycles of one month each, with biomass measurements, leaf counts, and physicochemical water analysis (pH, conductivity, nutrient concentrations, and contaminant removal) conducted throughout. Plant health and growth dynamics were monitored to assess tolerance to SGW exposure. Data analysis was performed to determine statistically significant differences between species in terms of pollutant removal efficiency and plant performance. Results revealed that Lythrum salicaria salicaria demonstrated the highest capacity for PMT removal, especially for DTG, MEL, MET, TCEP, and TFA. It also showed increased biomass and the highest evapotranspiration, suggesting a strong correlation between water uptake and pollutant removal. Festuca glauca glauca and Carex flacca flacca also exhibited notable PMT removal efficiency; however, Festuca glauca experienced biomass reduction, indicating sensitivity to SGW, while Carex flacca achieved removal with minimal evapotranspiration and positive growth, suggesting high water-use efficiency. All species absorbed nitrate (NO₃⁻) significantly, correlating with increased pH from 5.5 to around 6.5–7.0. Other nutrients such as PO₄³⁻, K⁺, Mg²⁺, Ca2+ and Cl - showed minimal change, likely due to precipitation and lower bioavailability at elevated pH levels. Partial denitrification was inferred from increases in nitrite (NO₂⁻). These findings underline the complexity of plant-contaminant interactions and the importance of selecting species based on both removal efficiency and resilience. This research contributes valuable insights into sustainable water management strategies in the context of climate change and water scarcity. Lythrum salicaria, Carex flacca, and Festuca glauca are identified as promising candidates for future integration in real green wall systems, combining ecological functionality with ornamental value

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