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Percorrer I. Componente Universitária por Objetivos de Desenvolvimento Sustentável (ODS) "06:Água Potável e Saneamento"
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- Anaerobic digestion of sludge from RAS and MBBR maturationPublication . Gonçalves, Francisco Matias; Castro, Carolina; Teixeira, Margarida RibauRecirculating aquaculture systems (RAS) are gaining popularity for their enhanced sustainability and increased fish production rates. However, the potential of saltwater RAS is constrained due to the absence of a standardized method for treating the saltwater sludge produced. Besides this, biofilter maturation in marine RAS is more challenging and less explored. Hence, this study aims to 1) Identify a suitable inoculum for Anaerobic Digestion (AD) of sludge produced in marine RAS and 2) compare different media substrates K3, K5 and Biochip on maturation and nitrification performance in Moving Bed Biofilm reactor (MBBR). Serum bottles were adapted as anaerobic reactors to test three different inocula for COD and TSS removal capacity and methane purity of the biogas produced: 1) Digested sludge from an operating anaerobic reactor (ETAR); 2) aquaculture earth pond sludge (A) and 3) a mix of ETAR and A (MIX). Regarding MBBR maturation, K3, K5 and Biochip’s MBBRs were operated with a hydraulic retention time (HRT) of 1 hour and 60 % filling ratio. AD results showed that ETAR and MIX removed 49.7 and 48.7% of COD while 67.4 and 82% of TSS, respectively. The methane purity found in the biogas of ETAR, MIX and A inocula were 0.22, 2.5 and 3.5%. Regarding MBBR maturation, start-up was completed on day 46 for K3 and K5’MBBR while on day 50 for Biochip’s MBBR. Biochip, K5 and K3 MBBR’s attained a TAN removal efficiency of 93.4, 87.5 and 66% while Biochip and K5’s MBBRs stabilized their nitrite removal efficiency at 89.3 and 88.9%. In contrast, K3 still showed an increasing trend, reaching 40%. Overall, this study showed that considering inocula previously exposed to salinity could be a better option for AD of marine RAS while MBBR’s with K5 and Biochip can achieve better water quality in FLATLANTIC RAS.
- Análise de métodos de classificação automática de uso do solo associadas à caracterização e quantificação de áreas regadas - Caso de estudo Campina de Faro, AlgarvePublication . Marques, Jonat Stefani Justa; Martins, Fernando Miguel Granja; Costa, Luís Ricardo Dias daA região Algarvia, com um clima temperado de características mediterrânicas, enfrenta uma crescente incidência de fenómenos de seca hidrológica prolongada, o que agrava de forma significativa os desafios relacionados com a escassez de recursos hídricos na região. A estimativa de valores do consumo de água subterrânea em áreas de regadio na região Algarvia consiste numa variável difícil de controlar e quantificar, não só devido ao elevado número de captações particulares, mas também por causa da variação meteorológica, que afeta os regimes de rega e das áreas regadas. Através da informação extraída pelo processamento de imagens digitais obtidas por deteção remota, juntamente com os valores das dotações de rega, pretende-se contribuir para estimativas do balanço hídrico do sistema aquífero de Campina de Faro mais precisas. Neste trabalho, estudou-se a classificação de uso e ocupação do solo para desenvolver uma metodologia de classificação automática de áreas agrícolas e espaços verdes regados, usando imagens de satélite Sentinel-2, aplicados à Campina de Faro. O projeto permitiu caracterizar com precisão as principais culturas agrícolas e espaços verdes regados na área de estudo e estimar o volume de água utilizado na rega com base nas dotações de rega das diferentes culturas. A metodologia desenvolvida é facilmente replicável para diferentes períodos e zonas, oferecendo uma ferramenta útil para a gestão dos recursos hídricos na região do Algarve. Os resultados obtidos permitiram a classificação das principais áreas e culturas regadas no sistema aquífero, bem como a quantificação da sua variação ao longo do tempo. Para além disso, foram aplicadas dotações de rega oficiais da DGADR, com o objetivo de estimar o volume de água utilizado na rega destas parcelas agrícolas, de forma a quantificar o volume de água extraído do aquífero para a agricultura e golfe. Os valores obtidos estão próximos dos valores oficiais reportados nos Planos de Gestão da Região Hidrográfica, o que demonstra, de certa forma, a fiabilidade dos resultados alcançados com esta metodologia.
- Assessing water requirements of pitaya (S. undatus) under greenhouse conditions: a first step towards optimizing irrigationPublication . Trindade, Ana Rita; Eller, Elda; Arozarena, A.; Neves, Maria Alcinda; Duarte, AmilcarThe Algarve region provides ideal edaphoclimatic conditions for cultivating subtropical and some tropical fruit species. Pitaya (Selenicereus spp.) is also aligned with Algarve’s goal of revitalizing fruit production through species that require less water. Recently introduced into commercial farming in Portugal, the expansion of this crop lacks more detailed information about its specific cultivation requirements. Although native to the humid forests of Central America, with consistent water availability, pitaya can also survive and produce in drier climates such as the Mediterranean. Nonetheless, to achieve good yields and high-quality fruit, adequate irrigation is essential. Understanding pitaya’s water needs can be challenging due to its natural water-conserving mechanisms, such as CAM (crassulacean acid metabolism) and water-storing cladodes. This study aims to clarify these needs firstly by determining the daily water consumption (DWC). At the University of Algarve, a greenhouse experiment monitors the DWC of 36 plants (S. undatus) in 4-L pots, enabling precise measurement of water consumption, with and without vegetative growth. During the summer, DWC ranged between 0.02 and 0.08 L day-1, influenced by the excessively high temperatures and the low humidity. These conditions significantly increased substrate evaporation rates. The results also suggest that pitaya growth showed no correlation with DWC. Since the summer trial confirmed the negative impact of excessively high temperatures, the same experiment was conducted in the autumnwinter season, when the plants grew in more favourable conditions. Pitaya’s exceptional water efficiency, evidenced by low summer DWC, makes it ideal for waterscarce regions. Substrate or soil covering, can further enhance water use efficiency, reinforcing its potential as a sustainable and economically viable crop. Preliminary results on the DWC of these plants indicate that pitaya’s evapotranspiration seems significantly lower compared to other irrigated fruit crops in the region.
- Assessment of piggery wastewater treatment in vertical flow constructed wetlands: role of plants and aerationPublication . Corrêa, D. O.; Ferreira, A.; Ribeiro, B.; Gogoi, J.; Karan, N.; Nalwad, A.; Ganguly, A.; Mutnuri, S.; Gouveia, LuisaPiggery wastewater (PWW), rich in pollutants, poses significant environmental risks if not properly treated. Natural treatment processes, such as constructed wetlands (combined action of plants, substrates, and microbes) and microalgae cultivation, offer sustainable and low-cost alternatives for managing these effluents while enabling resource recovery. This study represents an initial step toward optimizing key operational conditions, such as aeration (passive and active), vegetation presence, and the use of single or sequential Vertical Flow Constructed Wetlands (VFCWs), for the treatment of piggery wastewater, using different experimental setups, at a laboratory scale. Indoor experiments were conducted over an 8-week period to optimize operational conditions for the treatment of PWW. The VFCWs, arranged in two stages and operated in series through gravity flow, were fed daily and monitored weekly. The best removal rates of total Kjeldahl nitrogen (42.9 %), ammoniacal nitrogen (50.3 %), and chemical oxygen demand (20.5 %), were observed in the second stage of VFCW without aeration and with plant. Nitrate and phosphorus levels increased during the experiment, likely due to microbial activity within the substrate and plant root zones. The final goal is to treat the piggery wastewater from a rural farm in India, produce electricity (by a Microbial Fuel Cell), to generate an effluent suitable for microalgae cultivation, with the produced biomass intended for use either as a biostimulant to enhance cereal crops included in pig diets or as a direct nutritional supplement in pig feed.
- Can bivalve selective feeding shape phytoplankton community structure in the Ria Formosa coastal lagoon?Publication . Coscollá, María Nohales; Domingues, Rita; Barbosa, Ana Maria BrancoPhytoplankton plays a vital role in aquatic ecosystems, driving primary production, carbon cycling and nutrient recycling. The impact of bivalve feeding on phytoplankton biomass and community composition has been extensively documented. Nevertheless, there is currently no published research examining the impact of bivalve grazing and its selectivity on natural phytoplankton assemblages within the Ria Formosa coastal lagoon, a region responsible for 90% of Portugal's bivalve mollusc production. The aim of this study is to evaluate the impact of grazing by Mytilus galloprovincialis on natural phytoplankton assemblages in Ria Formosa. In particular, the effects of grazing on phytoplankton biomass, abundance, community composition, and the mussel's selectivity for different phytoplankton functional groups. The abundance and composition of phytoplankton were assessed using chlorophyll a concentration and microscopy: epifluorescence for pico- and nanophytoplankton and inverted for microphytoplankton. Mussel feeding was assessed by clearance rate. The microcosm experiments revealed a significant reduction in phytoplankton abundance due to mussel grazing in March, with a consistent decline in diatom abundance across all experiments. However, no significant changes were observed in phytoplankton biomass or community structure. The estimated per capita clearance rates of M. galloprovincialis ranged from 0.82 to 4.36 L h -1 individual-1 based on total chlorophyll a concentration, 1.07 to 1.95 L h -1 individual-1 based on total phytoplankton abundance, and 0.41 to 23.63 L h -1 individual-1 1 for specific phytoplankton groups. The results indicate that mussels selectively graze diatoms without significantly affecting overall phytoplankton biomass or community composition in Ria Formosa. Given the region's ecological and economic importance, understanding bivalve selective grazing is crucial for effective ecosystem management. Further studies should investigate the long-term impacts of this grazing on phytoplankton diversity and ecosystem resilience, particularly in light of changing conditions and growing aquaculture demands.
- Characterization of bacteria in seafood and environmental waters samples from Namibe (Angola)Publication . Calado, Beatriz Lopes; Cardoso, João; Power, Deborah MFoodborne diseases are a major burden worldwide and are very common and one of the major causes of death in underdeveloped countries. Coliform bacteria are a non-taxonomic group of Enterobacterales order that commonly inhabit the intestines of warm-blooded animals. While most coliform bacteria are not associated with foodborne illness, there are coliforms (faecal origin) that can cause diseases in humans of which most cases are associated with pathogenic E. coli strains. Therefore, detection of coliforms is commonly used as an indirect measure of quality control and safety of foods and waters for human consumption. The present study aimed to isolate and characterise coliform bacteria from bivalves that are used for human consumption and from their environmental seawater to identify species that may represent a potential risk for human health. Four different locations (Mucoio, Praia das Conchas, Sacomar, and Praia Amélia) in the coast of Namibe in Angola were sampled and microbiology techniques, molecular analysis, biochemical and virulence assays were performed to characterise the different isolates. Our results revealed that isolates correspond to Escherichia coli, Enterobacter spp., Klebsiella spp. and Citrobacter freundii and that the mussels collected from Praia das Conchas showed the highest fecal coliform contamination and diversity. At least 6 different strains of E. coli, 4 of Enterobacter spp. and 2 Klebsiella spp. and 1 of Citrobacter freundii were found and they show different resistance to cephalosporins and penicillins which are common antibiotics used in clinical. Virulence tests were performed using a representative strain from each species using the arthropod model Galleria mellonella and suggest that all strains are likely to be pathogenic and most or the larvae were death in the first 24h post injection. This study identify for the first time pathogenic coliforms bacteria in bivalve food samples and environmental waters from Namibe which may represent a health risk to the local population and the major causative agents of foodborne and other diseases.
- Contribution to the Iberian thermomediterranean oak woods (Spain, Portugal): the importance of their teaching for the training of experts in environmental managementPublication . Cano, E.; Piñar Fuentes, J. C.; Cano Ortiz, A.; Quinto Canas, Ricardo; Rodrigues Meireles, C.; Mauro, R.; Pinto Gomes, C. J.; Spampinato, G.; Musarella, C. M.The study of the holm oak forests of the lower and upper mesomediterranean of the south of the Iberian Peninsula, and new syntaxons of holm oak forests not assigned until now are contributed. The plant dynamics is provided and completed, and the importance of the learning of plant description and dynamics by university students, future environmental managers, is specified. Taking into account the strong anthropic action with the consequent destruction of holm oak forests, it is necessary to enhance the knowledge of plant dynamics to decipher the potential vegetation, and to be able to apply the vegetation series as a basis for agronomic and forestry management. In this work, we propose a new vegetation series. We propose the association Aristolochio baeticae-Quercetum rotundifoliae nova for the biogeographic sector Granadino-Almijarense (Montes de Málaga) and as a first dynamic stage of the microforest of Olea europea var. sylvestris obtained by deforestation. The study of the Iberian olive groves allows us to propose two new associations Aristolochio baeticae-Oleetum sylvestris and Ephedro fragilis-Oleetum sylvestris.
- Ecohydrological assessment of a complex river-floodplain system for the enhancement of its multidimensional potentialPublication . Guzmán, Damaris Rios; Chicharo, Luis; Jarosiewicz, PawełRiver floodplain systems are critical for sustaining biodiversity and providing a wide range of ecosystem services. However, climate change and anthropogenic activities increasingly disrupt the hydrological and ecological connectivity of these systems, red ucing their resilience to external pressures. The degradation of floodplains undermines key ecosystem services, including the support of terrestrial and aquatic biodiversity, the regulation of hydrological extremes such as floods and droughts, and the sequ estration of carbon. Given the global challenges of water scarcity and associated ecological consequences, there is an urgent need for innovative management strategies to enhance the mult idimensional roles of floodplains in water resource management, biodiversity conservation, and climate change adaptation. Therefore, this thesis focused on the study of the river floodplain system that was selected as the demonstration site for the ecohydrological project LIFE Pilica (LIFE19 IPE/PL/000005) in Central Poland. The study addresse d the hydrological connectivity within the river floodplain system during spring and early summer, assessing its effects on water quality. A particular focus was placed on phosphorus dynamics between the water and sediment compartments, aiming to propose management strategies that mitigat e excessive phosphorus release for a sustainable water retention in the floodplain area. Three primary hydrological connection s were identified between the studied floodplain, Pilica river and an upstream wetland . The connectivity decreased significantly throughout the study (from 0.185 m 3 s 1 in March to 0.002 m 3 s 1 in May )), with the first connection turning into a drainage source in April due to Pilica’s water level decrease . By May, the second source dried up, and the third was projected to cease at a river discharge below 12 m³s⁻¹ (R² = 0.94). Principal Component Analysis (PCA) revealed a greater difference between water quality from the o xbow l ake with the river ’s inflow (35.4%) than with the wetland’s outflow ( 15.5%). This shift underscores an increased risk of eutrophication in both water bodies, driven by prolonged residence times, nutrient accumulation, and the lack of water exchange from the river. Sediment analysis revealed significant differences in water content and organic matter between samples ( p < 0.05 at the studied floodplain part . Most sediments were rich in organic phosphorus and bound to Fe, Al, and Mn. Sorption tests showed greater phosphorus adsorption in air dried sediments and a high zero equilibrium phosphorus concentration (EPC₀), indicating a tendency to release phosphoru s when exposed to river water , thus highlighting the need of proper management prior increasing hydrological connectivity . In conclusion, the implementation of a water retention basin in the area will tackle the greatest threat to the studied river floodplain system: the progressive loss of hydrological connectivity. Furthermore, the potential risk of phosphorus release was ev aluated to refine the management strategy , ensuring it effectively mitigates nutrient loading and supports long term ecosystem health.
- Editorial: Endocrine regulation and physiological adaptation of stress response in aquatic organisms, volume IIPublication . Li, Yi-Feng; Li, Yiming; Campinho, Marco António; Fuentes, JuanAt the individual level, organisms develop many complex morphological and physiological adaptations to maintain homeostasis, of which endocrine regulation is the key. By adjusting physiological mechanisms, organisms adapt their response to the external environment, enabling the acquisition of new homeostatic equilibrium that allows survival. The physiological adaptative mechanism plays an important role in maintaining homeostasis and adapting to changes in the external environment. Well-known environmental factors such as ambient temperature, pH, ammonia nitrogen, salinity, and exposure to new pollutants can disrupt homeostasis, resulting in growth and physiological and endocrine disorders. Thus, in a rapidly changing climate, it is important to explore the biological adaptive regulation mechanism and endocrine regulation strategy under stress, which has an important impact on the protection of aquatic ecology. The main purpose of the Research Topic is to explore and discuss these potential physiological and molecular mechanisms to provide new insights for developing new green ecological activities.
- Efficacy of slow sand filtration enriched with trichoderma atroviride in the control of fusarium oxysporum in soilless cultivation systemsPublication . Matias, Pedro; Guerreiro David Coelho, Luísa Isabel; Reis, MárioOn a planet intending to move toward carbon neutrality while ensuring food security, maximizing water and nutrient use efficiency in agriculture is essential. Soilless cultivation offers a promising solution for food production, yet in substrate-based systems, excess nutrient solution (drainage) is often discarded to maintain phytosanitary safety, resulting in considerable water and nutrient waste. Reusing this drainage requires disinfection to eliminate pathogens. Among available methods, slow sand filtration (SSF) is ecological, economical, and simple, showing strong biological control potential, though not always fully effective against Fusarium oxysporum. Trichoderma atroviride, an antagonistic fungus, may enhance SSF performance. Its antagonistic capacity was evaluated in vitro via direct confrontation assays and in vivo using a closed-loop soilless cucumber cultivation system with eight treatment combinations of SSF, T. atroviride, and F. oxysporum. SSF reduced F. oxysporum incidence by approximately 48%, T. atroviride in irrigation by 44%, and SSF enriched with T. atroviride reached 58% disease incidence reduction, though this increase was not statistically significant. These results confirm that both SSF and T. atroviride can partially suppress F. oxysporum, but further optimization is needed for consistent and complete pathogen control.