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Molecular School (MS) is an extracurricular initiative intended to show relevant and complex concepts of chemical sciences to precollege students. The main goal is to motivate the participants to expand their awareness of chemical sciences and to acknowledge its relevance in everyday life, in order to stimulate the students to engage in chemistry undergraduate degrees. Here, we address the successful case of MS, implemented in Portugal, where recently, the universities have been facing significant difficulties in attracting new students to join chemistry-related courses. We report the first three editions of this free of cost preuniversity school, whose main subject is chemistry. All editions were held in the University of Coimbra, Portugal, and organized by PhD students of the department of chemistry of this institution. The three editions are discussed here, with particular focus on the last edition. Several participants ultimately chose chemistry BSc degrees to continue their education, which substantiates the positive outreach of this initiative. We believe MS can be replicated, adapted, and improved in other contexts and countries to increase the number of students enrolling chemistry university degrees.

Sandspits are important natural defences against the effects of storm events in estuarine regions, and their temporal and spatial dynamics are related to river flow, wave energy, and wind action. Understanding the impact of extreme wave events on the morphodynamics of these structures for current conditions and future projections is of paramount importance to promote coastal and navigation safety. In this work, a numerical analysis of the impact of a storm on the sandspit of the Douro estuary (NW Portugal) was carried out considering several mean sea level conditions induced by climate change. The selected numerical models were SWAN, for hydrodynamics, and XBeach, for hydrodynamic and morphodynamic assessments. The extreme event selected for this study was based on the meteo-oceanic conditions recorded during Hurricane Christina (January 2014), which caused significant damage on the western Portuguese coast. The analysis focused on the short-term (two days) impact of the storm on the morphodynamics of the sandspit in terms of its erosion and accretion patterns. The obtained results demonstrate that the mean sea level rise will induce some increase in the erosion/accretion volumes on the seaward side of the sandspit. Overtopping of the detached breakwater and the possibility of wave overtopping of the sandspit crest were observed for the highest simulated mean sea levels. [ABSTRACT FROM AUTHOR]

Seaweed assemblages include a variety of structuring species providing habitats, food and shelter for organisms from different trophic levels. Monitoring intertidal seaweed traditionally involves targeting small areas to collect data on species' biological traits, which is often labour intensive and covers only a small area of the rocky reef under study. Given the various applications for seaweeds and their compounds, there has been an increase in demand for biomass triggered by the development of new markets. Such biomass demand generates new challenges for biomass quantification and the definition of future in-take harvesting commercial quotas by regulating agencies. The use of Unoccupied Aerial Vehicles (UAVs) as a low-cost yet efficient monitoring solution, combined with new sensors such as multispectral cameras, has been proposed for mapping intertidal reefs and seaweed in particular. In this study, a new methodology was developed and validated to quantify intertidal seaweed biomass based on multispectral UAV imagery, which was made available through an easy-to-use QGIS plugin (named SWUAV_BIO) that automates such biomass estimation. This tool was applied to a case study where the standing stock of Fucus spp. beds located at Viana do Castelo rocky shore (northern Portugal) was assessed using UAV multispectral imagery, providing a reference for future UAV-based ecological studies. Although comparison with the in situ assessments showed that biomass was underestimated by 36%, the SWUAV_BIO plugin is a valuable tool, as it provides an expedited (albeit conservative) seaweed standing stock assessment that can be used to monitor seaweed populations, their changes, and assess the effect of harvesting. These data can be used for an informed and sustainable management of seaweed resources by the competent authorities. [ABSTRACT FROM AUTHOR]

In the current context of climate change, understanding the effects of the changing conditions on estuaries is of utmost importance to protect populations and ecosystems. Given the diversity of impacts depending on the region, there is a need for local and dedicated studies to understand and mitigate the risks. Numerical models can provide forecasts of extreme floods and sea-level rise (SLR). However, they can present inaccuracies. In this work, the ensemble technique was applied to improve the numerical modeling forecasting for estuaries by considering scenarios of extreme river flow discharges (EFDs) and SLR scenarios for 2050 and 2100. The simulations were performed for two different estuarine regions in northern Portugal, and the superensemble was constructed with the results of two different numerical models. The results differed per estuary, highlighting the importance of a local approach. For the Douro estuary dynamics, the results showed that for the EFD, the effects of the SLR were not noticeable, indicating that, in this estuary, the river component was more important than the maritime component. In contrast, the Minho estuary dynamics were found to be affected by the SLR along the whole estuarine region, indicating a maritime influence and a worsening of the flood conditions for future scenarios. [ABSTRACT FROM AUTHOR]

Many coasts suffer from prevailing erosion, with them being particularly vulnerable to predicted climate change impacts, threatening coastal ecosystems, their services, infrastructures and populations. Understanding coastal morpho-sedimentary dynamics is thus essential for coastal management. However, coastal vulnerability may differ locally, depending on exposure/protection and local geological and morpho-hydrodynamical features, suggesting that a local approach to erosion risk assessment is needed to identify and understand local patterns. Digital elevation models of a 14 km long coastal stretch in northern Portugal that were extracted from aerial surveys obtained between November 2008 and February 2019 were analysed to quantify changes in shoreline position and sediment budgets, both for the whole study area and for distinct beach segments. The observed dynamics were subsequently analysed by considering prevailing wave and wind intensities and directions. Overall and during the decade analysed, the beach–dune system of the studied stretch slightly increased in volume (0.6%), although the shoreline retreated (by 1.6 m on average). Temporal variability in coastal dynamics was observed at all of the temporal scales considered—from seasons to 5-year periods—with them being related to variability in ocean and wind patterns. There was a trend from accretional to erosional conditions, with the first 5-year period showing a mean increase in the beach–dune system's volume of 0.6% and a mean shoreline progradation of 1.5 m, followed by 5-years with 0.0% volume change and 3.1 m shoreline retreat. Locally, the dynamics were very variable, with shoreline dynamics ranging from 24.0 m regression to 51.5 m progradation, and sediment budgets from 213.8 m3 loss to 417.0 m3 gain, per segment and for the decade. Stretches with relatively stable morphologies and others with erosional or accretional trends were found, depending on the beach type, shoreline orientation and the presence of defence structures. Rocky beaches were the least dynamic and sandy beaches the most dynamic, with mean shoreline position changes of 0.0 m and −3.4 m, respectively, and mean sediment budgets of −1.1 m3 and −2.9 m3 per linear meter of coastline, respectively, for the studied decade. The observed dynamics showed how local conditions interacted with meteo-ocean conditions in shaping local morpho-sedimentary dynamics, stressing the importance of a local approach to coastal erosion monitoring and risk assessment. [ABSTRACT FROM AUTHOR]

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Abstract: There are currently only two places in Portugal were native Artemia parthenogenetica can still be found. All other known populations have been eradicated by the invasive species Artemia franciscana, which has caused great losses of Artemia biodiversity in the Mediterranean region. The diploid strains found at the Portuguese salines are therefore of high conservation value. This study aims to assess the survival of these native A. parthenogenetica strains and of A. franciscana under a variety of environmental conditions. The effects of water temperature and salinity, of photoperiod and food supply (shortage) were studied in an experimental setup. The Portuguese parthenogenetic Artemia populations showed great variability in their physiological response to different abiotic conditions, suggesting possible local adaptations in response to different selective pressures experienced. For most of the conditions studied A. franciscana outcompeted the Artemia strain from Aveiro, whereas the strain from Rio Maior was more resistant than the A. franciscana under conditions that were similar to its local habitat. Strain-specific resistance to chemical conditions, related to pollution, are appointed as a potential cause why A. franciscana did not successfully invade Aveiro saline. The saline of Rio Maior has possibly not yet been invaded due to the fitness of its local Artemia strain in combination with its inland location. [Copyright &y& Elsevier]

In situ measurements are key to depict the hydrodynamic patterns of estuarine regions. Whereas extended studies are available on major estuaries, there is still a lack of knowledge concerning smaller ones. In this study, the analyses of dedicated in situ campaigns are presented to unravel the hydrodynamic patterns of a small shallow-water estuary located in northern Portugal – the Ave Estuary – in view of a possible implementation of new ecosystem-based management measures to contain plastic pollution. The in situ campaigns performed, which monitored several parameters, such as water depth, salinity, temperature, turbidity and current velocity and bottom sediment grain-size, revealed a highly stratified estuary, with very strong vertical salinity gradients. The measured current velocities were low but, despite its low velocities and low river flows, this estuary revealed interesting hydrodynamic patterns associated with local and remote (oceanic) conditions. The currents were mostly generated by tides and estuarine circulation during low river flows and by river dominance during high river flows. However, the study demonstrated that the circulation is also influenced by the coastal conditions generated by the plume of a neighbouring estuary, which enhanced an oceanward transport in the estuarine surface layer and an upstream flow in the bottom layer, revealing the importance of considering coastal conditions to understand the circulation patterns of shallow-water small estuaries. [Display omitted] • Shallow-water small estuary hydrodynamic patterns analysed through in situ campaigns. • The Ave Estuary, Portugal, presented a strong stratification and very low currents. • Currents caused by tides, estuarine circulation, coastal conditions and river flow. • Influence of a neighbouring estuary (Douro Estuary) on the Ave Estuary circulation. [ABSTRACT FROM AUTHOR]

Rivers are amongst the most threatened ecosystems in Europe. To prevent further degradation and to improve their ecological status, effective mitigation and restoration actions are needed. Those actions are primarily based on the precision of the ecological assessment results. This study aims to assess the ecological status of two small Mediterranean rivers-the Âncora (AR) and the Ferreira (FR) rivers-through the analysis of biological (benthic macroinvertebrates and macrophytes), physico-chemical and hydromorphological quality elements. Specific objectives were to analyse variations of biotic and abiotic parameters amongst rivers, and amongst seasons and sites within each river, to confirm adequate temporal windows to develop the monitoring surveys. Results showed that only one AR site achieved a good ecological status in spring and summer, while the other sites presented a moderate ecological status in all seasons. FR sites had a moderate to bad ecological status in all seasons. Both rivers showed high levels of nutrients, particularly during spring and summer, and were found quite altered in terms of floristic composition of the riparian communities. The riparian forest and the forbs fringe were dominated by several alien woody species and nitrophilous communities, respectively. Based on a multidisciplinary approach, this study provides an in-depth description of the ecological status of two small Mediterranean rivers located in sites of European interest, as well as a sound basis for the management of the aquatic environments. Mitigation of diffuse pollution and restoration of the riparian zones are a priority to improve their ecological status.