Percorrer por autor "Calheiros, Cristina S. C."
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- Advanced treatment in constructed wetlands: the role of photocatalytic modules and nanostructured filtersPublication . Ojediran, Adetunji A.; Pereira, Sofia I. A.; Rosa-Santos, Paulo; Arenas, Francisco; Dolbeth, Marina; Ntougias, Spyros; Calheiros, Cristina S. C.Background & Aim: Constructed wetlands (CWs) have emerged as a leading nature-based solution (NBS) for wastewater treatment, offering multiple benefits such as low maintenance costs, high pollutant removal efficiency, carbon sequestration, biodiversity enhancement, and aesthetic value (Justino et al., 2023; Kadlec, 2008). However, in tourism facilities, two major challenges affect wastewater management: seasonal variability in wastewater composition and volume, and the lack of connection to centralized treatment systems (Calheiros et al., 2015). To address these issues, a decentralized CW system was developed, operating alongside a septic tank for wastewater collection. This horizontal subsurface flow CW has been operational since 2010. The study aims to integrate photocatalytic modules and nanostructured filter technologies with CW to enhance water quality for irrigation. Methods: wastewater quality characterization will be performed according to national legislation and the efficiency of the photocatalytic modules and nano filters will be assessed. Results: CW efficiency is being assessed, and ongoing studies are being carried out related to the best approach for the implementation of the photocatalytic modules and nanostructured filters technologies. Conclusions: By integrating advanced filtration and photocatalytic technologies, this research intends to develop a highly efficient, self-sustaining, and ecofriendly wastewater treatment system suitable for the tourism industry. The findings will contribute to the broader application of CW in decentralized wastewater management and sustainable water reuse strategies, most especially in a tourism facility.
- Aerobic granular sludge sequencing batch reactor performance under fluorinated pharmaceuticals shock loadingsPublication . Moreira, Irina S.; Amorim, Catarina L.; Ribeiro, Ana R.; Maia, Alexandra S.; Mesquita, Raquel B. R.; Calheiros, Cristina S. C.; Rangel, António O. S. S.; Loosdrecht, Mark C. M.; Tiritan, Maria E.; Castro, Paula M. L.The widespread usage of pharmaceuticals is of increasing concern. Aerobic granular sludge sequencing batch reactors (AGS-SBR) constitute a promising technology for the treatment of wastewaters, however how the removal of carbon and nutrients can be affected by such micropollutants is largely unknown. This study evaluates the impact of different fluorinated drugs (ofloxacin, norfloxacin, ciprofloxacin and fluoxetine) on the performance of an AGS-SBR. During 468 days, a sequence of intermittent, alternating and/or continuous shock loads of pharmaceuticals were applied to an AGS-SBR and the effects on the main biological processes were evaluated. Here we report on the effect of fluoroquinolones on reactor performance. The organic removal, measured by COD, was not markedly affected by pharmaceuticals shock loads. Ammonium and nitrite were practically not detected in the bioreactor effluent indicating that the presence of the pharmaceuticals did not inhibit nitrification, whereas accumulation of nitrate in the effluent was observed, indicating that denitrification was affected. Phosphate removal was affected to some extent. There was no evidence of biodegradation whereas adsorption of the target pharmaceuticals to the AGS was observed, which were gradually released into the medium after withdrawal from the inlet stream.
- Aplicação de leitos de macrófitas ao tratamento de efluentes do sector dos curtumes.Publication . Calheiros, Cristina S. C.; Rangel, António O. S. S.; Castro, Paula M. L.
- Aplicação de um sistema de análise por injecção sequencial à monitorização da eficiência de operação de um leito de plantasPublication . Mesquita, Raquel B. R.; Santos, Inês C.; Calheiros, Cristina S. C.; Castro, Paula M. L.; Rangel, António O. S. S.
- Application of experimental constructed wetlands to the wastewater treatment in a leather companyPublication . Calheiros, Cristina S. C.; Rangel, António O. S. S.; Castro, Paula M. L.
- Assessment of trombidiidae (acari) as biondicators for wastewater treatment in a constructed wetlandPublication . Magalhães, João Pedro Correia de Sousa; Pereira, Sofia; Leong, Chi Man; Xu, John Hongxi; Calheiros, Cristina S. C.Introduction and aim: The family Trombidiidae (superorder Acariformes), with common names such as red velvet mites, exhibits dietary habit shifts throughout their development. Larvae are parasitic, while nymphs and adults transition to a free-living, soil-dwelling predator stage (Durkin et al., 2021). Predation by these mites is usually done in rocks, tree stumps, plants, leaf litter, and moss, with other arthropods and their eggs being their prey. These hunting environments fit the habitat created by constructed wetlands (CWs) biological wastewater treatment systems, mimicking the processes and conditions that occur in natural wetlands. A macrofauna assessment was performed in a CW located in a tourism house in the north of Portugal, near Ponte de Lima, to understand its performance after 15 years of operation, with Trombidiidae mites being found. Method: This work involved seasonal sampling of macrofauna at multiple collection spots within and around the CW, with pitfall trapping being complemented by substrate core sampling to assess both belowground and aboveground communities. This occurred across the Autumn of 2022 to the Summer of 2023. The collected specimens were sorted by taxonomic group, identified further, when possible, photographed and quantified, with statistical analysis currently underway. Results and discussion: The presence of Trombidiidae was confirmed in all seasons in the 15-year-old CW, implying that this CW maintains favorable environmental conditions year-round. This tracks with the hypothesis of the environment created by the CW mimicking the natural habitats in which these predators hunt. The simultaneous occurrence of spiders, preferred hosts for the larval stage of these mites, within the same system indicates that their life cycle is likely sustained within this system. The fact that these spiders are numerous might also imply a robustness in their population, with their numbers not being heavily affected by the parasitism. As both parasites and predators of the biodiversity presented in the CW, Trombidiidae may contribute to a deeper understanding of the food web within these systems, providing proof as bioindicators of the ecological and habitat benefits CWs can provide. Conclusion: Preliminary results indicate a robust and well-structured ecosystem, with the consistent presence of Trombidiidae across all seasons, suggesting a stable population, with hosts for the larval stage, ensuring their cycle of life.
- Biodiversity assessment in a floating treatment wetland established in a stormwater pondPublication . Calheiros, Cristina S. C.; Ilarri, Martina; Godinho, Mariana; Castro, Paula M. L.; Pereira, Sofia I. A.Floating treatment wetland (FTW) are a nature-based solution delivering a wide range of ecosystem services when applied in water bodies, such as lakes and rivers. They are recognized for delivering biodiversity, aesthetic integration, and water quality enhancement through phytoremediation processes, although research is still needed to go deeper into the processes underlying the performance of these systems and evaluate the extent of biodiversity promotion especially on pond ecosystems. This study aimed to assess the plant establishment and biodiversity associated with an FTW set up in a rural artificial stormwater pond, with a polyculture comprising Iris germanica, Acorus gramineus, Caltha palustris, and Typha latifolia set in a cork agglomerate platform. For this, it was assessed the culturable bacterial communities associated to the floating platform and the rooting system, and the macroinvertebrates associated to the FTW and to the pond margin. Culturable bacterial communities colonizing the floating platform biofilm and the plant rhizosphere were isolated, identified by 16S rRNA, and characterized for their ability to produce plant growth-promoting substances (e.g., indole-acetic acid, siderophores). There was a high bacterial genera diversity associated with the FTW and with the ability to produce plant growth-promoting substances. Bacterial strains with outstanding growth-promoting traits can be used in the future to support phytoremediation strategies or plant resilience to climate change-related abiotic stresses. Regarding the biodiversity of macrofauna, namely macroinvertebrates, associated with FTW, they were mostly from the order Odonata. The FTW attracted mainly individuals of the genus Coenagrion, which represented more than 80 % of the associated fauna. The full life cycle of dragonflies and damselflies occurred in the FTW. These systems proved to be a hotspot of biodiversity supporting water and landscape management plans, besides aesthetics integration. This study gives new insights into broadening the FTW applications in stormwater or prospects to polluted water.
- Biological processes for industrial wastewater treatment- case study in the leather industryPublication . Calheiros, Cristina S. C.; Rangel, António O. S. S.; Castro, Paula M. L.
- Biotreatment of tannery wastes with a PhytoSystemPublication . Calheiros, Cristina S. C.; Rangel, António O. S. S.; Castro, Paula M. L.
- Constructed wetland implemented in a tourism unit for wastewater treatmentPublication . Calheiros, Cristina S. C.; Mesquita, Raquel B. R.; Brix, Hans; Rangel, António O. S. S.; Castro, Paula M. L.