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- An ecological assessment of fish recruitment in Lagos through the monitoring of BiohutsPublication . Berimbau, Luís Martim Almada; Erzini, KarimMarine ecosystems are crucial hubs of biodiversity and face increasing threats from human activities, particularly in coastal areas serving as nurseries for fish recruitment, a pivotal factor influencing the abundance and diversity of fish populations. This study focuses on evaluating the abundance, biodiversity and recruitment dynamics through an underwater visual census, with a specific focus on the innovative Biohut structures installed in Marina de Lagos and their potential contribution to marine biodiversity conservation. This study focused on ecological processes such as habitat association and the impact of environmental and biological factors, and assessed the Biohuts potential to enhance abundance, biodiversity and recruitment. The methodology employed underwater visual censuses and environmental data collection for a comprehensive assessment from September 2023 to June 2024. The period between spring and early summer had the highest values in terms of abundance of recruits. The results indicate that the Biohuts significantly increased fish abundance, biodiversity and recruitment when compared with the control areas inside and outside the marina. In conclusion, Biohuts are effective tools for enhancing fish abundance, biodiversity, and recruitment in urbanized coastal areas. They provide a promising solution for habitat restoration, marine biodiversity conservation and can also serve as platforms to study key processes for sustainable management of fisheries as it is the case of fish recruitment.
- Analysis of cultural and provisioning ecosystem services use: a comparative study of artificial reefs, rocky areas, and sandy bottoms in the AlgarvePublication . Camelo, Ana Maria Madiedo; Ramos, Jorge; Leitão, FranciscoArtificial reefs are human made structures that are deployed in the seabed to provide multiple economic, social and ecological benefits. Artificial reefs have emerged as a highly effective strategy to provide ecosystem services, such as habitat protection, restoration, and recreation. Despite their acknowledged benefits, there remains a limited understanding of how these reefs are currently being used by the local communities. The present study aims to identity and analyze the use of provisioning and cultural ecosystem services provided by the artificial reefs located in the south coast of Portugal, in comparison with rocky areas and sandy bottoms. To achieve this, a satellite dataset comprising automatic identification system (AIS) records with nine months of hourly location data for recreational and fishing vessels (including purse seiners and multi-gear) was utilized to identify and analyse high-density areas. Statistical tests were conducted to further assess the data. The results indicate that, within the selected study area, sandy bottoms are the most intensively used habitat for fishing activities, with multi-gear vessels being the predominant type, proving to be a significant type of habitat that provides essential ecosystem services. In contrast, artificial reefs were found to be used for recreational and fishing activities, but with lower density values, while rocky areas were the least used ones.
- Analysis of sediment transport in coastal areas within the AX-COAST ProjectPublication . Husemann, Paul Lasse; Costas, Susana; Lima, Márcia; Coelho, CarlosThis report documents my six-month internship at the University of Aveiro, where I contributed to the AX-COAST: Cross-shore features and internationalization of the COAST tool project, an initiative aimed at improving coastal management strategies by enhancing the COAST tool for modelling shoreline evolution in different scenarios of sediment transport conditions and coastal defence interventions. (...)
- Assessing the impact of beach nourishment on reducing wave overtoppingPublication . Sproul, Vega Alexander; Garzón Hervás, Juan Luis; Mendes, DiogoAs zonas costeiras densamente povoadas podem estar sujeitas aos efeitos das tempestades costeiras, que promovem galgamento oceânico e consequentes inundações costeiras. As obras de defesa costeira, como esporões e defesas longitudinais aderentes, têm sido usadas para proteger contra estes perigos e salvaguardar as áreas urbanas costeiras. Nas últimas décadas, no entanto, houve uma mudança de paradigma promovendo o uso de outras soluções de engenharia, como a alimentação artificial de praias. A praia de Quarteira é um exemplo desta mudança de paradigma. Delimitada por um campo de esporões e apoiada por uma defesa longitudinal aderente, ambos construídos no início da década de 1970, a praia foi alvo de uma alimentação artificial em 1998, com outra planeada para 2024. Apesar da sua implementação, não se quantificou a eficácia da alimentação artificial na mitigação do galgamento oceânico em Quarteira. Esta dissertação pretende determinar a eficácia do projeto de alimentação artificial planeado para Quarteira na redução do galgamento oceânico com recurso a modelação numérica. Utilizando o modo não hidrostático do modelo XBeach, este estudo simula o galgamento oceânico para três cenários: antes da alimentação artificial, após a alimentação artificial e cinco anos após a alimentação artificial. Simulou-se o impacto de cinco tempestades sintéticas, com diferentes alturas significativas da agitação marítima e períodos de onda, para períodos de retorno variando entre 5 e 65 anos. Foram analisadas as relações entre a crista do revestimento, a largura da berma e os caudais médios de galgamento das ondas obtidos nas simulações do XBeach. Esta análise levou ao desenvolvimento de duas equações empíricas para estimar os caudais médios de galgamento em função das condições hidrodinâmicas (altura significativa e comprimento de onda ao largo) e da geometria da alimentação de praia (largura da berma). Este trabalho contribuiu para o desenvolvimento de uma metodologia para dimensionar e avaliar a eficácia dos projetos de alimentação artificial de praias.
- Assessment of wave overtopping at Praia da Vitória, Terceira, Azores, with SWASH modelPublication . Baddavidana, Dinush Shayaman Priyankera; Pinheiro, Liliana; Garzon, Juan L.; Zózimo, Ana CatarinaThe primary objective of this dissertation is to enhance the accuracy of overtopping predictions using the SWASH (Simulating WAves till SHore) model, for inclusion in the Early Warning System (EWS), HIDRALERTA, currently operational in Praia da Vitória. While existing tools within HIDRALERTA offer valuable insights, they have limitations in accurately representing waves and overtopping details. To address these limitations, this research tested the capabilities of the SWASH model by simulating past storm events and typical wave conditions across the two-dimensional model of the entire port and bay areas with complex coastal structures and bathymetry. Outcomes of the simulations were compared to predictions from the NN_OVERTOPPING2 neural network and observed images from extreme events. In the SWASH model, coastal structures were modelled as impermeable layers, with bottom roughness incorporated to enhance energy dissipation from roughness and seepage. An unstructured triangular mesh was used for the computational domain. Manning’s coefficient for the outer slope of the south breakwater, with tetrapod armour units, was calibrated using a physical model test conducted in February 2025 at the National Laboratory of Civil Engineering (LNEC). The model was replicated in SWASH at prototype scale, using two test cases that resulted in overtopping for calibration. The results demonstrate that the SWASH model effectively simulates wave propagation and overtopping in harbour and bay areas, especially over complex coastal structures. Its accuracy in estimating wave propagation and overtopping is sensitive to wave energy interactions with the bottom and slopes, influenced by the Manning coefficient. While unstructured meshes enable large-domain simulations, the quality of the mesh affects both prediction accuracy and computational time. The model is stable when using implicit time integration but unstable with explicit methods. Despite some simulation instability, most simulations reached the maximum allowed simulation time on the National Distributed Computing Infrastructure (INCD) cluster. The model’s accuracy is heavily dependent on bathymetric data, with results generally aligning with NN_OVERTOPPING2 predictions and observed images from extreme events, although underpredictions can occur. Parallel processing is currently limited to structured grids in SWASH and, there is potential for efficiency improvements with unstructured meshes. Future studies should compare SWASH results with field data to fully assess its performance.
- Changes in storm impacts along the Portuguese sandy coast for different climate scenariosPublication . Kazi, Maysha; Loureiro, Carlos; Ferreira, ÓscarStorms can result in extensive damage to the socioeconomic and environmental balance along the sandy coasts. Therefore, it is crucial to understand how the hydro-geomorphological response of sandy barriers will change due to future changes in storminess. This study aims to investigate future storm impacts on two contrasting sandy barriers along the Portuguese coast, Maceda and Tavira located respectively in the northwestern and southeastern coast, and evaluate how these will change in relation to the present situation. The approach is based on the application of the storm impact scale for the present and future climate change scenarios (mid- and end-century). Modelled wave, storm surge, and sea level data were combined with high-resolution topographic data and a conceptual model of barrier evolution to determine dune morphological parameters and impact regimes for future scenarios. The main findings of this work are that, extreme water levels will consistently increase throughout the twenty first century, mostly due to the contribution of sea level rise when compared to changes in storminess. From mid to the end-century, a reduction in dune crest elevations can be observed on the southernmost section of the Maceda coast and on the western to central section of the Tavira island. Compared to the current situation, by the mid- and end-century the intensity of collision and overwash regimes is expected to become severe in Maceda. For Tavira island, the most severe storm impact regimes are expected to be overwash and inundation, which will occur over almost half of the barrier island by 2100. From the mid-to-end century for all storm return periods, the mean overwash potential will increase substantially on the southernmost section of Maceda and on the west to the central section of Tavira island, while the mean inundation potential will gradually rise along with the mean overwash potential in Tavira. The influence of sea level rise and potential changes on the barrier morphological characteristics, particularly on the dune crest, are crucial factors influencing future changes to storm impacts.
- Compound flooding on an estuarine environment: case study of tagus estuaryPublication . Romero, Fabian Yesid Soler; Almeida, Luis Pedro; Hervas, Juan L. GarzonThe combined occurrence of coastal, fluvial and/or pluvial flood drivers can lead to compound flood events, which can trigger devastating social, economic, and ecological impacts, particularly in low-lying zones, including estuarine environments. A great number of these areas, which are home to significant populations worldwide, are increasingly at risk, as the intensity, phasing and frequency of such drivers are projected to change. These flood-induced impacts arise from the potential increase in inundation magnitude due to the non-linear interactions between various flood drivers, where their combined effects can exceed the simple sum of their individual contributions. Understanding their joint impacts and accurately estimating compound flood magnitudes is therefore essential for effective coastal management and disaster risk reduction. In this study, a numerical modeling framework was applied to analyze the interaction between different flood drivers (storm surge, peak river discharge, extreme rainfall and astronomical tides) in the Tagus Estuary. The first phase involved a coupled hydrodynamic model (MOHID), implemented to simulate tidal, wave, and current circulation within the estuary using oceanic and riverine boundary conditions. Based on these results, a flood model (SFINCS) was applied to simulate flooding processes along the northern and southern margins of the estuary under various scenarios. The flood model was validated using a storm event that occurred in the study area in December 2022. Subsequently, joint probability and extreme value analysis for 100-year return period values were estimated for the flood drivers and used to define multiple modeling scenarios along with different Sea Level Rise projections. These scenarios were designed to examine the flood driver’s interaction, focusing on the flood magnitudes in the context of compound flooding. This study demonstrated that compound events resulting from the interaction of pluvial/fluvial and coastal drivers can increase flood extent and depth by three to four times compared to events driven solely by coastal forces, such as a storm surge coinciding with spring tides in the estuary. Furthermore, the analysis revealed that rainfall is the primary cause of flooding in the Tagus Estuary.
- Estimating wave runup using satellite multi-spectral imageryPublication . Ilekura, Idowu Oselumhe; Almeida, Luis Pedro; Ferreira, Óscar ManuelThe wave runup is one of the most important processes responsible for coastal hazards, including overtopping or erosion. Understanding and predicting wave runup in any coastal environment is crucial for risk and vulnerability assessment studies. Nevertheless, the lack of field observations of wave runup is one of the main limitations of the predictability of this process. Past studies have used shore-based video monitoring techniques to observe wave runup in coastal areas. However, these studies were limited in time (data acquisition periods of several months or years) and space (spatial coverage of a single beach or extension of hundreds of meters or a few kilometres). In recent years, remote sensing, in particular Satellite Imagery, have improved the capability of the onboard sensor (e.g., improved spatial resolution of optical sensors) and revisit times (time between consecutive data collection in the same point on the earth’s surface), making of this technology one with the most significant potential to overcome earth sciences challenges. The present project’s general objective is to utilize multi-spectral imagery to monitor wave runup in coastal areas, representing a novel approach compared to past runup monitoring methodologies. Wetsand (boundary between the dry and wet beach) and Waterline (boundary between the water and the beach) were extracted from the satellite images as potential runup proxies. The satellite-derived runup proxies were compared to existing wave runup formulations. The error quantification was performed using statistical descriptive parameters (e.g., RMSE, correlation coefficient, and Bias). The waterline-derived runup proxies demonstrated high correlation (Bias = 0.35, R² = 0.63, RMSE = 0.65) with the existing runup formulation, whereas the Wetsand proxies exhibited lower correlation (Bias = -0.41, R² = 0.17, RMSE = 0.95). Averaging the Wetsand and Waterline proxies improved the Bias and RMSE to 0.12 and 0.611, respectively. The optimal formulation for each proxy was employed to correct the runup formulation, which was then used to compute the 𝑅2, resulting in a refined runup formulation. The corrected formulations for each proxy were utilized to predict extreme runup events. The waterline and the average Wetsand/Waterline proxies outperformed the Wetsand proxies during low wave and tide conditions. In contrast, the Wetsand proxy outperformed both alternatives in predicting extreme runup under high wave and tide conditions. Overall, the study noted the prospect of using satellites to measure and estimate runup globally.
- From the ground to the sky: new challenges for territory and landscape photography across cultures in the drone eraPublication . Souza, Davi Magalhães de; Loureiro, NunoSpatial patterns on different scales, intertwined with ecological processes on different organizational levels, are an utmost important field of study in landscape ecology. Spatially explicit human impacts, whether direct or indirect, are among the most valued topics, and cartographic figures are a suitable way of presenting part of the obtained results. Historical and recent maps, and various levels of remote sensing, from orthophotography to satellite imagery, are among the sources of spatial information sought and studied. All of these information sources offer a vertical view, from top to bottom, with different spatial resolutions. Photographs taken at ground level, that offer a horizontal view, are equally useful. But between one and the other sets of data sources, there is a gap, either in scale or in privileged point of view to survey, fastly or accurately, places and landscapes. Recently, drones have emerged as perfect tools for observing and recording the spatial-visual properties of places and landscapes, and also to fill the aforementioned gap because they easily provide views from above, horizontally, and also oblique panoramic gazes, in bird's eye views. They are low-cost and easy-to-use equipment, although subject to some legal restrictions, increasingly powerful in features such as fly autonomy and image resolution. After the first generations of drones with RGB cameras, drones with multi-spectral and thermal cameras also became common, allowing to further deepen the analysis and interpretation of places and landscapes. Incorporating curricular units that teach drone piloting and imagery use is an urgent need in Landscape Architecture and related fields globally. Despite the growing importance of drone technology in various domains, the integration of drones into educational curricula remains limited in many regions. This should follow a foundational focus on Photography, Place, and Landscape Representation. Similarly, greater concern and integration between landscape and site representation are emerging alongside the new challenges presented by the age of drones. Thus, this article seeks to create a conceptual model that serves as a basis for landscape representation challenges arising from recent technological developments, both at ground level and for photographs taken by unmanned aerial vehicles (UAVs). The diagram, as well as conceptualised based on analytical and holistic values, is also tested in an exercise undertaken in Armação de Pêra, in the municipality of Silves, Portugal. It expresses a coherent methodology and results that prove the veracity and differences between ground and aerial photographs, subsequently associating them with cultural, social and religious values. The aim of this article is to identify New Challenges for Territory and Landscape Photography Across Cultures in the Drone Era. The specific objectives are as follows: (i) to examine how culture influences landscape and place, which will be discussed in Chapter 2; (ii) to analytically conceptualise, through a theoretical diagram, the spatialisation of place and landscape, based on drone photography; and (iii) to conduct a case study that validates the established diagram. Thus, the article answers the following guiding question: - How are the new challenges for territory and landscape photography perceived across cultures in the drone era? This article consists of five main chapters. The first chapter characterises the study and its relevance. The second chapter presents the theoretical framework that sustains the thesis, based on the different cultures and representations of the landscape. The third chapter offers an analytical perspective on the various facets of landscape and photography, as well as conceptualisation through a diagram created. The fourth chapter tests the concept through a case study in Armação de Pêra, Portugal, using photographs taken with drones as well as ground-level images. The fifth and final chapter presents a discussion of the case study and concludes with the importance of integrating photography, technology and drones into curricular units on landscape representation.
- Harvesting rainwater - the relevance of hydrometeorological factors on rainwater quality and demonstration of the mitigation approach using green roofs and adsorption materialsPublication . Vargas, Julián Camilo Ríos; Jarosiewicz, Paweł; Chicharo, LuisWater pollution is one of the main challenges facing the world at present. As water is a vital resource, it is essential that it meets minimum quality standards in order to be used as drinking water, as well as for the ecosystem health. Rainwater harvesting has received attention in recent years due to its potential use as a water source, and important as climate-adaptation strategy. However, rainwater often contains pollutants that can impact negatively on human health and aquatic ecosystems. In response to these challenges, Nature-based Solutions (NbS) have emerged as innovative approach that mimic natural processes to enhance ecosystem services, such as water quality improvement. Examples of NbS for rainwater management include green roofs, bioswales, and raingardens, which help improving rainwater quality before it infiltrates or drains to water bodies, protecting rivers, reservoirs and lakes from contamination. To further enhance the effectiveness of NbS in rainwater treatment, the use of natural and innovative sorbent materials like dolomite and biochar have demonstrated good potential. In this way, the project aimed to assess the influence of hydrometeorological factors such as rainfall intensity (RI), antecedent dry period (ADP), and first flush on rainwater quality in the urban catchment (Łódź City, Poland) and to evaluate the efficiency of green roof technology in terms of rainwater retention and rainwater quality. Finally it aimed to identify and compare the potential enhancement of rainwater treatment through the use of innovative sorbent materials. The results demonstrated significant differences in rainwater quality between the two sites studied, particularly concerning pollutants like total phosphorous, indicating spatial impact on water quality. The research confirmed that the runoff from roofs produce elevated concentrations of pollutants including total suspended solids (TSS), total nitrogen (TN), total phosphorous (TP), and total organic carbon (TOC). A positive correlation was observed between ADP and pollutants concentration, while RI showed variable correlations across sites, suggesting that factors such as roof material, age, slope and roughness also could play a role in determining pollutant concentrations. Additionally, higher concentration of pollutants were found during the initial time of rainfall. In addition, the study identified that green roofs can significantly improve water retention and enhance rainwater quality by incorporating sorbent materials that mitigate the release of pollutants, such as phosphorus.