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- Dissolved oxygen dynamics in Ria Formosa Lagoon (South Portugal) - A real time monitoring station observatoryPublication . Cravo, Alexandra; Rosa, Alexandra; Jacob, J.; Correia, CátiaDissolved oxygen (DO) is considered one of the most important environmental variables of water quality. This work aimed to provide, for the first time, insights regarding DO dynamics on a representative site of the productive Ria Formosa coastal lagoon, south Europe, using a real time monitoring station observatory (acquiring data every 15 min) deployed for a period of two and a half years. This comprehensive data set represents an added value contributing to a better understanding of the DO variability throughout analyzing semidiurnal, daily, fortnightly tidal cycles (spring tide vs. neap tide), seasonal and interannual periods. This observational station was able to capture distinct temporal signatures, including episodic upwelling and meteorological events advancing the knowledge about the functioning of Ria Formosa. DO was highly variable presenting an evident seasonal distribution with the maximum concentration in spring and the minimum in summer night periods. Critical values < 5 mg/L were recorded only in 3% of the global data set with negligible hypoxia events, showing infrequent DO stressful conditions in the study area. In addition, the disclosure of its did dynamics over long periods, provided by this data set, allows to determine the impact of biological activity upon the DO variability and related ecosystem metabolism behavior (autotrophic vs. heterotrophic), through the metric estimation of Net Ecosystem Metabolism (NEM). NEM in the study area revealed to be slightly heterotrophic along one year of observation, reflecting the median percentage of DO saturation (93%). The acquired data set is highly valuable and can contribute to Ria Formosa management and protection, which is imperative for building knowledge-based societies.
- Understanding the bioaccumulation of pharmaceutical active compounds by clams Ruditapes decussatus exposed to a UWWTP dischargePublication . Cravo, Alexandra; Silva, Sofia; Rodrigues, João; Cardoso, Vítor Vale; Benoliel, Maria João; Correia, Cátia; Coelho, Maria Rosário; Rosa, Maria João; Almeida, Cristina M.M.Twenty-four pharmaceutical active compounds (PhACs) were evaluated in the soft tissues of clams Ruditappes decussatus exposed along a 1.5-km dispersal gradient of the treated effluent from an urban wastewater treatment plant discharging in Ria Formosa, and compared with those in the marine waters and discharged effluents. The clams were exposed for 1 month, in June-July 2016, 2017 and 2018. PhACs were quantified by high performance liquid chromatography coupled to tandem mass spectrometry after the quick, easy, cheap, effective, rugged and safe (QuEChERS) method (clams) or solid-phase extraction (water samples). The most representative PhACs in the effluents and receiving waters (regardless of the tidal dilution effect) were diclofenac, carbamazepine and caffeine (on average <= 2 mu g/L) and only caffeine exhibited significant inter-annual differences, with higher values in 2017. In turn, the most bioaccumulated PhACs in clams were caffeine (0.54-27 ng/g wet weight, significantly higher in 2016) and acetaminophen (0.37-3.7 ng/g wet weight, significant lower in 2016). A multivariate principal component analysis showed (i) PhAC bioaccumulation primarily depended on biotic factors (clams length and weight), (ii) PhAC physicochemical properties Log Kow, pKa and water solubility interplaying with water abiotic variables were more relevant for explaining data variability in water than the physical dilution/tidal mixing, (iii) this process, reflected by the salinity gradient, had a tertiary role in data variation, responsible for spatial discrimination of marine waters. This study provides a better understanding of PhACs bioaccumulation by clams Ruditapes decussatus in real environmental conditions, under the influence of urban treated effluent dispersal in Ria Formosa coastal lagoon, a major producer of bivalves, ultimately disentangling key factors of PhAC bioaccumulation.
- Impacts of decommissioning and upgrading urban wastewater treatment plants on the water quality in a shellfish farming coastal lagoon (Ria Formosa, South Portugal)Publication . Jacob, J.; Correia, Cátia; Torres, Ana Flor; Xufre, Gustavo; Matos, André Filipe; Ferreira, Cristina; Reis, Margarida; Caetano, Sandra; Freitas, Carla; Barbosa, Ana B.; Cravo, AlexandraRia Formosa is a productive coastal lagoon, located on the south coast of Portugal, and represents the largest national producer of shellfish bivalves (ca. 90% production). This ecosystem is subjected to various anthropogenic pressures, including the discharge of urban wastewater treatment plants (UWWTP), which impacts the lagoon water quality. This study aimed to assess the impact of alterations in the functioning of two UWWTP on the water quality of Ria Formosa, based on chemical variables, phytoplankton composition ( including potential harmful species) and faecal contamination. During the period September 2018 - October 2019, water sampling was conducted along dominant longitudinal gradients of the effluent dispersion from the discharge point (1-2 km), for two sites: a decommissioned (OP) and a modified (FO) UWWTP. After modification, the later started receiving a higher influent volume (ca. 40%), under an innovative technology system (biological treatment in aerobic granular sludge). Based on chemical water quality variables, phytoplankton and indicators of faecal contamination, a significant improvement along the longitudinal gradient from the discharge point was observed after OP decommissioning. This improvement was fast, being detected two months after decommissioning, positively affecting areas used as shellfish farming grounds. However, distribution patterns of bacteriological indicators and regular shellfish harvesting interdictions suggested an alternative source of faecal contamination after OP decommissioning. At FO, both chemical variables and bacteriological indicators of faecal contamination revealed a slower improvement, only six-months after the UWWTP alteration. Before that, increased and highly variable ammonium, chlorophyll a concentration, phytoplankton abundances and Escherichia coli densities, revealed an unstable phase. Overall, a lower water quality at FO in respect to OP reflected not only a higher effluent volume but also more restricted water circulation for the former.
- Biomarker responses of the clam ruditapes decussatus exposed to a complex mixture of environmental stressors under the influence of an urban wastewater-treatment plantPublication . Silva, Sofia; Cravo, Alexandra; Ferreira, Cristina; Correia, Cátia; Almeida, Cristina M. M.To evaluate the potential impact of an urban wastewater-treatment plant on Ria Formosa coastal lagoon, a sentinel species, the clam Ruditapes decussatus, was exposed along a gradient of the effluent's dispersal for 1 mo. Three exposure sites were selected to study the responses of 3 biomarkers: electron transport system, acetylcholinesterase, and lipid peroxidation. As complementary data, morphometric measurements, condition index, and lipid and protein content were considered together with in situ physicochemical characterization of the sites (temperature, salinity, pH, and dissolved oxygen). Electron transport system activity levels were between 35.7 and 50.5 nmol O-2/min g protein, acetylcholinesterase activity levels ranged from 2.6 to 3.8 nmol/min g protein, and lipid peroxidation ranged from 174.7 to 246.4 nmol malondialdehyde/g protein. The exposure sites shaped the response not only of biomarkers but also of "health" parameters (protein, lipids, and condition index). Lipid peroxidation was the most responsive biomarker also associated with electron transport system, especially at the closest site to the urban wastewater-treatment plant. Because of the presence of complex mixtures of contaminants in urban effluents, biomarker responses can provide valuable information in environmental assessment. However, it is vital to identify all biological and ecological factors induced by the natural life cycle of clams. Abiotic factors can mask or overlap the response of biomarkers and should be considered in a multibiomarker approach. (C) 2020 SETAC
- Nutrients and chlorophyll-a exchanges through an inlet of the Ria Formosa Lagoon, SW Iberia during the productive season - Unravelling the role of the driving forcesPublication . Cravo, Alexandra; Cardeira, Sara; Pereira, Catarina; Rosa, Monica; Alcantara, Pedro; Madureira, Miguel; Rita, Filomena; Correia, Cátia; Rosa, Alexandra; Jacob, J.Despite the advances and increase of observations of physical and chemical processes to better understand thefunctioning of coastal environments, a large gap still exists in quantifying exchanges and interactions betweenadjacent coastal systems. It is important to bear in mind that the dynamics and mass exchanges depend on thevariability of the driving mechanisms and respond to several time scales (tidal, seasonal and inter-annual). Thegeneral objective of this work was to unravel the role of the driving forces on the nutrients and chlorophyll-aexchanges at the Ancão inlet of Ria Formosa lagoon during the most productive season - spring. This is thesmallest inlet of the western system, the closest to continental interface and the one where migratory patterns areevident. So, the changes along time could be more evident there than at the other two inlets of the westernsector. Ancão inlet will serve as a reference to compare the mass budgets exchanged with the ocean with theother two inlets. Specifically, this work intends to: i) better understand the behaviour of this inlet; ii) its role inthe mass exchanges; and iii) its interplay with phytoplankton productivity during the peak season. In thiscontext, the transport of water, nutrients and chlorophyll-a(proxy of phytoplankton density) were estimatedacross the Ancão inlet section during the spring season. Surveys were conducted under extreme fortnightly tidalconditions during 2007, 2009 and 2012, covering different hydrodynamic, meteorological and environmentalconditions. To estimate the mass transport,field velocities, nutrients and chlorophyll-aconcentrations weremeasured concurrently along its cross section. Results show that although the hydrodynamic and morphologicchanges recorded at this inlet provoked a loss of hydraulic efficiency apparently these did not markedly affectthe mass exchanges during the spring productive season. Globally, the contribution and intensity of the me-teorological/physical, chemical and biological drivers superimposed those affected by tides, reflected in thedifferences between thefive surveys conducted. Upwelling was frequent during the spring season and played akey role on the exchanges and mass transport through the Ancão inlet. Data also show that nutrients behaveddissimilarly; silicate was consistently exported, nitrate mostly imported, dependent on the intensity of upwellingand biological consumption, while phosphate generally followed the direction of residual circulation.Chlorophyll-ashowed a general import except in both 2012 campaigns, when it was exported in small amounts(< 1 kg). Data support that during spring season, particularly in periods when upwelling is relevant, theavailability of nutrients on the coast will promote afterwards the growth of phytoplankton that enters andfertilizes the Ria Formosa, increasing its productivity. The estimated amounts are relative to the smallest inlet ofthe western sector of Ria Formosa. In consequence, it may be anticipated that through the other main inlets fromthis sector the exchanges are intensified and may enhance their contribution to the Ria Formosa fertilization.
- Human stem cells for cardiac disease modeling and preclinical and clinical applications—are we on the road to success?Publication . Correia, Cátia; Ferreira, Anita; Fernandes, Mónica T.; Silva, Bárbara M.; Esteves, Filipa; Leitao, Helena; Bragança, José; Calado, SofiaCardiovascular diseases (CVDs) are pointed out by the World Health Organization (WHO) as the leading cause of death, contributing to a significant and growing global health and economic burden. Despite advancements in clinical approaches, there is a critical need for innovative cardiovascular treatments to improve patient outcomes. Therapies based on adult stem cells (ASCs) and embryonic stem cells (ESCs) have emerged as promising strategies to regenerate damaged cardiac tissue and restore cardiac function. Moreover, the generation of human induced pluripotent stem cells (iPSCs) from somatic cells has opened new avenues for disease modeling, drug discovery, and regenerative medicine applications, with fewer ethical concerns than those associated with ESCs. Herein, we provide a state-of-the-art review on the application of human pluripotent stem cells in CVD research and clinics. We describe the types and sources of stem cells that have been tested in preclinical and clinical trials for the treatment of CVDs as well as the applications of pluripotent stem-cell-derived in vitro systems to mimic disease phenotypes. How human stem-cell-based in vitro systems can overcome the limitations of current toxicological studies is also discussed. Finally, the current state of clinical trials involving stem-cell-based approaches to treat CVDs are presented, and the strengths and weaknesses are critically discussed to assess whether researchers and clinicians are getting closer to success.
- Patterns and predictors of phytoplankton assemblage structure in a Coastal Lagoon: Species-specific analysis needed to disentangle anthropogenic pressures from ocean processesPublication . Lima, Maria João; Barbosa, Ana B.; Correia, Cátia; Matos, André; Cravo, AlexandraPhytoplankton are dominant primary producers and key indicators in aquatic ecosystems. Understanding the controlling factors on the structure of phytoplankton assemblages is fundamental, but particularly challenging at the land–ocean interface. To identify the patterns and predictors of phytoplankton assemblage structure in the Ria Formosa coastal lagoon (south Portugal), this study combined phytoplankton abundance along a transect between the discharge point of a wastewater treatment plant and a lagoon inlet, over two years, with physico-chemical, hydrographic, and meteo-oceanographic variables. Our study identified 147 operational taxonomic units (OTUs), and planktonic diatoms (60–74%) and cryptophyceans (17–25%) dominated the phytoplankton in terms of abundance. Despite strong lagoon hydrodynamics, and the lack of spatial differences in the phytoplankton abundance and most diversity metrics, the multivariate analysis revealed differences in the assemblage structure between stations (p < 0.001) and seasons (p < 0.01). Indicator analysis identified cryptophyceans as lagoon generalists, and 11 station-specific specialist OTUs, including Kryptoperidinium foliaceum and Oscillatoriales (innermost stations) and potentially toxigenic species (Pseudo-nitzschia and Dinophysis; outer lagoon station, p < 0.05). Water temperature, pH, and nutrients emerged as the variables that best explained the changes in the phytoplankton assemblage structure (p < 0.001). Our findings provide insight into the relevance of local anthropogenic and natural forcings on the phytoplankton assemblage structure and can be used to support the management of RF and other coastal lagoons.
- Integrating physical and biogeochemical processes and oceanic exchanges at a coastal lagoon in Southern West EuropePublication . Cravo, Alexandra; Jacob, José; Rosa, Alexandra; Correia, CátiaCoastal lagoons are highly productive systems and the quantification of mass fluxes, which is of paramount importance for the sustainable management of these systems, remains poorly studied. In this context, a detailed study was conducted to better understand the exchanges between the productive coastal lagoon Ria Formosa (South-West Europe) and the ocean. The exchanges of water, nutrients, chlorophyll-a and suspended solids between the main inlets (Faro-Olhao inlet - BFO; Armona inlet - BAR; and Ancao inlet - BAN) and adjacent channels (Faro - CF and Olhao - CO) and the adjacent ocean were estimated along complete semidiurnal tidal cycles, under extreme fortnightly tidal ranges and different seasonal and environmental/oceanographic conditions. The net tidal prism was highest during spring tides. Among the three inlets, BFO was the most important in terms of exchange, followed by BAR and BAN. Net transport at BFO was lowest during the Summer campaign, although it exported material that fertilised the adjacent coast. The persistent net export of suspended solids and ammonium suggests the higher biological productivity of Ria Formosa compared to that found in coastal waters. In the Winter campaign, after a period of rainfall and increased land runoff, there was a remarkable export of matter, on which, ammonium and suspended particles exported can exceed 0.3 times and almost 0.9 times, respectively, those imported from coastal water. However, the import of phosphate and nitrate can be attributed to a weak coastal upwelling event, as well to low consumption and nitrification at this period of low temperature. During the Spring and Autumn campaigns, the Ria Formosa was fertilised either by upwelling events or due to rapid consumption of nutrients by phytoplankton in this shallow system. BFO and the other two inlets of the western sector of Ria Formosa are interconnected by CF and CO. The higher nutrient transport was recorded at CF, despite the highest nutrients concentrations was recorded at CO. The data show the strong link between physical and biogeochemical processes with meteorological/oceanographic factors. The study showed that associated biological processes are superimposed on the tidal effect in this system. Data from this study could be used as a reference, particularly important for management of Ria Formosa, a productive system where bivalves production depends deeply on water quality. In addition, the nutrient concentrations and mass exchanges resulting from the different processes can be used as a reference for other lagoon systems where shellfish production is practised.
- Dynamics of CO2, CH4, and N2O in Ria Formosa coastal lagoon (southwestern Iberia) and export to the Gulf of CadizPublication . Sierra, A.; Ortega, T.; Forja, J.; Rodrigues, M.; Cravo, Alexandra; Correia, CátiaA first characterization of greenhouse gases had been carried out to study their role and impact in a productive transitional coastal system of the southern Portugal – Ria Formosa lagoon. To this purpose, the partial pressure of CO2 (pCO2) and the concentration of dissolved CH4 and N2O have been measured. Two surveys were carried out during 2020, at low tide under typical conditions of Spring (March) and end of Summer (October). The samplings sites were distributed along the costal lagoon covering: i) inner areas with strong human impact (influence of different flows of treated wastewater discharges); and ii) main channels in connection with the main inlets to study the exchanges with the ocean. In general, the highest values of the three greenhouse gases were found at the inner studied areas, especially affected by the disposal of treated effluents from wastewater treatment plans, in October. The mean water - atmosphere fluxes of the CO2, CH4 and N2O are positive, showing that the study
- Water quality of a southwest Iberian coastal lagoon: Spatial and temporal variabilityPublication . Rosa, Alexandra; Cravo, Alexandra; Correia, Cátia; Jacob, JoséThe present work aims to characterize Ria Formosa water quality considering its spatial, and temporal variability at two scales: short-term (among seasons) and long-term to evaluate its evolution over the past 40 years, by comparing six historical datasets with data obtained in this study. To attain these goals, four field surveys under different seasons and/or weather conditions were conducted between 2017 and 2019 at seven sites along the Ria Formosa, covering the water bodies specified for this system. In situ measurements (temperature, salinity, pH and dissolved oxygen) and water sampling for determination of nutrients, chlorophyll a and suspended solids were taken every 2 h at each site, during complete semidiurnal tidal cycles. Moreover, these data were complemented with in situ data acquired at a high frequency (every 15 min) by a real time observational station deployed at an inner area, close to a main channel, where the anthmpogenic pressure is more intense. Data analysis clearly depict a spatial variability pattern along the Ria Formosa, as well as a temporal heterogeneity, influenced by the contribution of precipitation, sediments, wind and water exchanges with the adjacent ocean. Between sampling sites, the lowest variability of water quality parameters occurred at the boundary coastal station, at the main inlet, in permanent connection with the ocean, while the maximum variability was found at both the lagoon edges, mainly due to the shallowness of the water column. Temporally, the highest concentrations of nutrients were obtained during the Wet/rainy conditions survey, under the influence of runoff. The lowest concentrations of nutrients were attained during the Summer, except for phosphate, due to consumption by phytoplankton. Although the sampling frequency along time has been limited, Ria Formosa water quality data from the last 40 years shows a decreasing trend in nutrients concentration and a marginal increase of dissolved oxygen, suggesting a water quality improvement over time, in contrast with other coastal lagoons that are showing a water quality deterioration due to an increasing anthropogenic pressure. Altogether, these are relevant aspects to consider regarding Ria Formosa present and future management, including climate change and anthropogenic pressures susceptibility assessment and to use them within an international context by comparison with other similar systems.