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- Factors driving sediment compositional change in the distal area of the Ria de Vigo (NW Spain): oceanographic processes vs. paleopollutionPublication . Virginia Alves Martins, Maria; Cazelli, Lucas; Yhasnara, Missilene; da CristineSilva, Layla; Barros Saibro, Murilo; Bobco, Fabia Emanuela Rafaloski; Rubio, Belen; Ferreira, Bruna; Castelo, Wellen Fernanda Louzada; Santos, José Francisco; Ribeiro, Sara; Frontalini, Fabrizio; Martínez-Colón, Michael; Pereira, Egberto; Antonioli, Luzia; Geraldes, Mauro; Rocha, Fernando; Sousa, Silvia Helena Mello e; Dias, JoaoWe analyze potential Late Holocene metal contamination along a sediment core collected in the distal zone of Ria de Vigo (North Spain). Statistical treatment of the dataset based on a multiproxy approach enabled us to identify and disentangle factors influencing the depositional processes and the preservation of the records of this activity in the area over the last approximate to 3000 years BP. Some layers of the analyzed core have significant enrichment in Cu and a moderate enrichment in Ag, Mo, As, Sb, S, Zn, Ni, Sn, Cd, Cr, Co, Pb, and Li. The enrichment of these elements in some layers of this core may be related to mining activities that have taken place since classical times in the region. Successive phases of pollution were identified along the core KSGX24 related to the Late Bronze Age (approximate to 3000-2450 years BP), Iron Age (approximate to 2450-1850 years BP), Roman times (approximate to 1850-1550 years BP), Middle Ages (approximate to 1250-500 years BP), and industrial and modern (approximate to 250-0 years BP) anthropic activities. The protection of the Cies Islands, the erosive and transport capacity of the rivers in the region, oscillations of the oceanographic and climatic regime, atmospheric contamination, and diagenetic sedimentary processes might have contributed to the accumulation and preservation of this record in the distal region of the Ria de Vigo. The studied core shows that the industrial and preindustrial anthropic impacts caused an environmental liability and contributed to the presence of moderate to heavy pollution of various metals in surface and subsurface sediment layers in the distal sector of the Ria de Vigo, which could be a hazard to biota.
- Extending the DPSIR framework to analyse Driver-Pressure-State-Impact-Response of sand dune management in Manawatu-Whanganui (New Zealand) since the 19th centuryPublication . Sampath, D. M. R.; Freitas, J. G.; Dias, JoaoCoastal sand dunes are multifunctional landscapes with rich biodiversity. In New Zealand, with the establishment of European settlement around 1840, dunes in the Manawatu-Whanganui region were affected due to the removal of their vegetation cover by human activities and animal grazing. As a result, sand drifted further inland affecting villages, infrastructure and agricultural areas. The main response was to introduce marram grass (Ammophila arenaria) used in Europe to stabilize dunes. This solution caused significant environmental impacts as marram grass turned invasive and native habitats of fauna and flora significantly decreased.This paper focused on the long-term analysis of aspects related to sand dune management in the region during two-time frames: 1) from the 19th to the late 20th century and 2) from then on to the early 21st century, using the innovative spiral DPSIR (Driver-Pressure-State-Impact-Response) framework. Data for this study comes from historical records, scientific literature and present management reports.The integrated spiral framework allows for establishing the connections between historical and future man-agement initiatives for mitigating and adapting to environmental impacts due to socio-economic drivers and their pressures. The study reinforces the paradigm shift from dune stabilization before the late 20th century to the restoration of stabilized dunes to make them active for enhancing native biodiversity should be again assessed in the context of sea-level rise during this century. Coastal managers should adopt an optimized solution between these two extreme solutions adopted from the 19th century to the present, by considering long-term and interdisciplinary analysis to better understand the systems' evolution and the full consequences of human actions.
- Response of Benthic Foraminifera to organic matter quantity and quality and bioavailable concentrations of metals in Aveiro Lagoon (Portugal)Publication . Martins, Maria Helena; Silva, Frederico; Laut, Lazaro L. M.; Frontalini, Fabrizio; Clemente, Iara M. M. M.; Miranda, Paulo; Figueira, Rubens; Sousa, Silvia H. M.; Alveirinho Dias, João M.This work analyses the distribution of living benthic foraminiferal assemblages of surface sediments in different intertidal areas of Ria de Aveiro (Portugal), a polihaline and anthropized coastal lagoon. The relationships among foraminiferal assemblages in association with environmental parameters (temperature, salinity, Eh and pH), grain size, the quantity and quality of organic matter (enrichment in carbohydrates, proteins and lipids), pollution caused by metals, and mineralogical data are studied in an attempt to identify indicators of adaptability to environmental stress. In particular, concentrations of selected metals in the surficial sediment are investigated to assess environmental pollution levels that are further synthetically parameterised by the Pollution Load Index (PLI). The PLI variations allowed the identification of five main polluted areas. Concentrations of metals were also analysed in three extracted phases to evaluate their possible mobility, bioavailability and toxicity in the surficial sediment. Polluted sediment in the form of both organic matter and metals can be found in the most confined zones. Whereas enrichment in organic matter and related biopolymers causes an increase in foraminifera density, pollution by metals leads to a decline in foraminiferal abundance and diversity in those zones. The first situation may be justified by the existence of opportunistic species (with high reproduction rate) that can live in low oxic conditions. The second is explained by the sensitivity of some species to pressure caused by metals. The quality of the organic matter found in these places and the option of a different food source should also explain the tolerance of several species to pollution caused by metals, despite their low reproductive rate in the most polluted areas. In this study, species that are sensitive and tolerant to organic matter and metal enrichment are identified, as is the differential sensitivity/tolerance of some species to metals enrichment.
- Is the sea the enemy? Occupation and anthropogenic impacts at Costa da Caparica (Portugal)Publication . Pereira, Olegário Nelson Azevedo; Bastos, Maria Rosário; Ferreira, José Carlos; A. Dias, JoãoThis article explores the development of human occupation and the anthropogenic impacts at Costa da Caparica, a Portuguese coastal town that faces several challenges concerning coastal erosion processes. A historical long-term analysis was made, mainly through medieval and modern writing sources, crossing such textual data with geology, geography, and other related scientific disciplines studies regarding the coastal erosion problems of the study area. Therefore, from the Middle Ages to the present, human actions concerning this area were examined. The sea was first seen as an income, due to tourism, and later seen as a danger. It is argued that human behaviors were the main cause of historical problems and also the present vulnerabilities and risks associated with this coastal stretch of the Portuguese littoral. We must search the past for answers to understand present problems and think about the future. This is the main purpose of this paper: to contribute to a better knowledge concerning coastal sustainability based on the results of past human actions, as a way to avoid such mistakes in the future.
- An analysis of coastal sand dune management in Oregon (United States) from the 19th to the 21st centuryPublication . Sampath, D.M.R.; Freitas, J.G.; A. Dias, JoãoThe Drivers -Pressures -State -Impact -Response (DPSIR) framework was employed to understand the land use policies developed to manage coastal sand dunes and their consequences in Oregon, United States of America, during two contrasting periods: from the 19th to the late 20th century and from there to the early 21st century. A combination of historical data and scientific literature was used for this study. Dune destabilization became a socio-economic issue as Euro-Americans settled in Oregon in the 19th century. Ammophila arenaria and Ammophila breviligulata were widely used for stabilization. This led to a paradigm shift regarding dunes, at a time when their management was becoming more complex due to socio-natural factors. As non-native beachgrasses turned invasive causing the loss of biodiversity and habitats, their removal became the focus to restore the active dunes to support the natural processes of the ecosystem. However, the removal of these beachgrasses, particularly, Ammophila arenaria, results in low dune heights, increasing the risk of coastal flooding by reducing their effectiveness as a natural defense against sea -level rise and extreme storm surges. The reason for the contrasting dune management policies in Oregon since the 1930 s is that the management response to environmental impacts due to human drivers creates new drivers, pressures, and corresponding impacts, as shown in the DPSIR analysis. Thus, land use policies for managing coastal dunes in Oregon and other places must balance efforts to restore the native biodiversity while minimizing coastal flooding in a context of accelerating and continuous sea -level rise in the 21st century.
- An approach to the contribution of anthropogenic actions for the Araruama lagoonal system (SE Brazil) geomorphological evolutionPublication . Pereira, Olegário Nelson Azevedo; Rodrigues, Maria Antonieta Da Conceição; Alveirinho Dias, João ManuelThe first studies regarding the constitution of the Araruama lagoonal system, located in the Rio de Janeiro state (SE Brazil), were carried out by Alberto Ribeiro Lamego. This author supported the thesis that it had resulted from the formation of a sand barrier (called Massambaba) due to the longitudinal transport of large quantities of sediments through coastal drift currents, and the growth of spits parallel to the shoreline. However, most recent studies largely rejected it, sustaining that the confinement of this hydric environment was the result of the growth of two sand barriers during the Pleistocene and Holocene times (120.000 to 7.000 years before present - BP) due to the sea level changes. The hypothesis that we suggest, is that both propositions are acceptable and complementary. This study aims to demonstrate that, despite the opinions on the formation of the double sand barrier, deposition of sediments by coastal drift currents at the end of the Holocene, and especially in recent chronologies, also contributed to the establishment of this lagoon system. In our opinion, the increased sediment supplies due to human activities contributed to the formation of the inner spits and the nearby sea sandbar. Its orientation was influenced by the existence of the island of Cabo Frio, that allowed the formation of the tombolo that almost connected it to the continent. Through the analysis of historical and cartographic documents related to the colonization and economic exploitation of the region, it is evident that the anthropogenic actions played a significant role in the sandy spits formation. Of these, special emphasis is placed on the agriculture and deforestation that contributed to the increase of sedimentary accumulation. This work demonstrate that the analysis of historical documents can provide information and contribute to the understanding of recent coastal developments.
- Digital interventions for emotion regulation in children and early adolescents: systematic review and meta-analysisPublication . Reynard, Sally; Dias, Joao; Mitic, Marija; Schrank, Beate; Woodcock, Kate AnneBackground: Difficulties in emotion regulation are common in adolescence and are associated with poor social and mental health outcomes. However, psychological therapies that promote adaptive emotion regulation may be inaccessible and unattractive to youth. Digital interventions may help address this need. Objective: The aim of this systematic review and meta-analysis was to synthesize evidence on the efficacy, feasibility, and acceptability of emotion regulation digital interventions in children and early adolescents aged 8 to 14 years. Methods: Systematic searches of Web of Science, MEDLINE, PsycINFO, EMBASE, Education Resources Information Centre, ACM Digital Library, and IEEE Xplore up to July 2020 identified 39 studies, of which 11 (28%) were included in the meta-analyses (n=2476 participants). A bespoke tool was used to assess risk of bias. Results: The studies evaluated digital games (27/39, 69%), biofeedback (4/39, 10%), virtual or augmented reality (4/39, 10%), and program or multimedia (4/39, 10%) digital interventions in samples classified as diagnosed, at risk, healthy, and universal. The most consistent evidence came from digital games, which reduced negative emotional experience with a small significant effect, largely in youth at risk of anxiety (Hedges g=-0.19, 95% CI -0.34 to -0.04). In general, digital interventions tended to improve emotion regulation, but this effect was not significant (Hedges g=0.19, 95% CI -0.16 to 0.54). Conclusions: Most feasibility issues were identified in diagnosed youth, and acceptability was generally high across intervention types and samples. Although there is cause to be optimistic about digital interventions supporting the difficulties that youth experience in emotion regulation, the predominance of early-stage development studies highlights the need for more work in this area.
- Emotionally expressive motion controller for virtual character locomotion animationsPublication . Silva, Diogo; Santos, Pedro A.; Dias, JoaoStyle and emotional expressiveness are essential aspects of virtual character computer animation. For a virtual character to display different emotions, motion capture data conveying each desired style has to be recorded, even if the baseline motion is the same. Animators then have to refine and conjoin each recording in order to create the final animations making it a timely and costly process. Although there have been efforts made into the automatic generation of motions, the problem persists that, for each new desired emotion, reference data displaying said emotion has to be readily available and a new motion has to be learned from scratch. By combining Machine Learning with Emotion Analysis - in particular Laban Movement Analysis and the Pleasure, Arousal, Dominance Emotional State Model - we have developed a system that is capable of not only identifying the perceived emotion of locomotion animations but that also allows users to alter the character's expressed emotion in real time and without the need of additional data.
- A Historical View on Coastal Erosion: The Case of Furadouro (Portugal)Publication . De Freitas, Joana Gaspar; Dias, JoaoThe village of Furadouro, on the north-western coast of Portugal, is emblematic of current problems of coastal management. The purpose of this article is to analyse the interaction between human communities and the coast in Furadouro, in order to understand how practices and arrangements have contributed to potentiate coastal erosion effects in the last century. The conceptual tools of 'socio-natural sites'; 'co-evolution'; and 'socio-natural sites as nexus of practices and arrangements' guide this investigation. The methodology adopted is socio-ecological long-term research. Data used comes mainly from primary historical sources (church registers, minutes of local authorities' meetings and newspapers) and secondary literature (local writers and monographs). Historical information was cross-referenced with geomorphological data to allow for a more global approach to the coastal erosion phenomenon. The analysis of the evolution of Furadouro shows that human activities determined the increase of coastal erosion problems, not only by contributing to the decrease of sand on the beach, but also by destroying its natural protection structures the dunes. The reconstruction of past coastal landscapes and human intervention gives us a better understanding of the complex and intertwined history of this socio-ecological site, also offering a model of analysis and interpretation that can be applied to other cases around the world.