2024-10-14 2024, Volume 7 Issue 1

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  • Kyriakos E. Kontopyrakis , Adonis F. Velegrakis , Isavela N. Monioudi , Alexandra Ćulibrk

    The aim of the present contribution has been to present a methodological framework to gauge/assess the perceptions and identify the policy priorities of local-decision-makers for the management of the coastal zone under a changing climate, on the basis of structured ‘interviews’ of the local decision makers. The framework was applied in two different coastal areas in Greece: a) Elefsina, an urban-industrial area west of Athens with a long industrial history (and the 2023 European Capital of Culture); and b) the Aegean island of Santorini/Thera, a major international tourist destination due to the rare aesthetics of its volcanic landscape. The framework implementation showed that a) policy prioritization is characterized by an (understandably) overarching objective to address immediate environmental and socio-economic challenges in short time tables due also to constraints in appropriate human and financial resources and the reliance on higher governance (regional/national) levels; b) policy axis and action prioritizations are controlled by the local environmental setting and development model; c) interestingly for coastal municipalities policy actions associated with the study/protection of coastal ecosystems ranked very low albeit for different stated reasons; and d) climate change impacts and adaptation have not been prioritized highly in both coastal municipalities, in contrast to the large impacts and needs for adaptation projected for these areas and the evolving policy and legislation frameworks. It appears that higher efforts should be made in terms of the assessment of climate change impacts, and the dissemination of the assessment results and the relevance of the evolving policy and legislation regimes to the local policy makers.

  • Elaine Baroni de Oliveira , Alice Newton , Camilo M. Botero

    This study analyzes the content of internet ratings of beaches to identify the indicators used. The methodology used an exploratory internet survey using the term ‘best beaches’ in five languages. For each site, the ranking method used was extracted and the indicators considered were listed, where applicable. Of the 70 websites analyzed, 47 ranked the beaches (67%) but less than 50% used indicators. The remaining were based on the opinion of the editorial board, personal experience, and users’ perceptions. The most used indicator was the color of water, followed by the color of the sand. These results show that the majority of ‘best beaches’ lists are based on subjective criteria. They are an overview of places that appeal to the person that wrote the page and are not scientifically or analytically based. Even when indicators are considered, these are mostly a reflection of the idea of an idealized beach, crystal blue waters with white or gold sand. The actual quality of the beach, including water quality, carrying capacity, and ecosystem balance, is not addressed. Although visual attractiveness is a key element for the public, these rankings should incorporate a wider range of indicators to fully assess the quality of a beach.

  • A. F. Velegrakis , D. Chatzistratis , T. Chalazas , C. Armaroli , E. Schiavon , B. Alves , D. Grigoriadis , T. Hasiotis , E. Ieronymidi

    The aim of this contribution is to provide a brief overview of the current and future earth observation (EO) technologies that can be used to assess and manage the EU coastal flood risk, together with the pertinent international and EU policies and legislation. The review has shown that EOs have become an indispensable technology for the assessment and management of the coastal flood risk, and their role will increase further in the future when EO information of higher resolution and accuracy become available. With regard to the relevant policies and legislation, their common thread is associated with the promotion and facilitation of the development of appropriate data and tools for high-quality and timely geo-spatial information based on EO technologies. In Europe, in particular, this development is promoted and facilitated by an array of international and supra-national (EU), interacting policies and legislation. It appears, however, that additional initiatives and technological progress in EO functionalities and the information technology are needed together with more targeted policy and legislation frameworks to provide vital information for the management of the coastal flood risk.

  • Gerardo M. E. Perillo , Mariana I. Zilio , Fernando Tohme , M. Cintia Piccolo

    Based on a free energy approach, we propose the estimation of an ecosystem’s Inner Value, which is both non-instrumental and objective, reflecting the ecosystem’s value for itself as a natural entity, abstracted from any human valuation. The ecosystem services approach has become the dominant criterion for studying human and natural relationships, but this and similar approaches concentrate on the human advantage giving little or no regard for the well-being of the ecosystem. Although there is concern about preserving and recuperating damaged ecosystems, we seldom consider how much the ecosystem values itself. Then, we propose that Inner Value could be a tool to evaluate and model ecosystems’ health before any anthropic disturbance, allowing comparison with the impact these disturbances may have in the future. We also suggest that it should be a requirement for any Environmental Impact Assessment.

  • Nidhin Krishna Kadalassery Radhakrishnan , Jeyabalan Sangeetha , Jadav Mulji Alabhai , Poornendu Jayasree

    • Microplastic contamination is a major concern in river ecosystems.

    • Microplastic in two bivalve species were characterized at Chandragiri River India.

    • The microplastics had diverse shapes and were composed of five different polymers.

    • This study emphasizes the need to tackle river microplastic pollution.

  • Elaine Baroni de Oliveira , Alice Newton , Camilo M. Botero

    Beach rankings are very frequent on the internet; however, the information provided on how these rankings are made is often unclear and their content is mostly subjective. In addition, the vast majority of these rankings do not take into account the fact that beaches are coastal eco-systems. The aim of the research was to develop an objective framework to rank the quality of beaches worldwide. The framework integrates indicators to assess the socio-ecological system quality and can be used as a basis for effective beach management. The methodology involved the collection, evaluation and grouping of indicators into domains and categories. Moreover, a measurement technique and a 5-point rating score for each indicator was used. Weights were calculated for different beach types using an analytical hierarchical process and the methodology was validated by a focus group of beach management experts. The quality value of each beach was calculated through equations and the results were presented in graphs inspired by the Circles of Sustainability and the Ocean Health Index. The theoretical application was tested on Portuguese beaches. The framework presents a holistic assessment of four domains: Recreation, Protection, Conservation and Sanitary. The resulting Beach Ranking Framework (BRF) is an objective, holistic framework designed to communicate with society, unlike the existing beach quality assessments.

  • K. Sian Davies-Vollum , Daniel Koomson , Debadayita Raha

    Lagoons are a major coastal environment in West Africa. They provide a plethora of resources, ecosystem services and economic benefits yet a diverse set of inter-connected stressors are a challenge to their sustainability. A scoping study of the published literature pertaining to lagoons within the region was undertaken to reveal the nature of these stressors and identify gaps in knowledge, providing a resource to inform coastal management practices and reveal areas for future study. Thirty-one lagoons were identified from the scoping exercise covering Nigeria, Benin, Togo, Ghana, Cote D’Ivoire, Liberia and Senegal. The DAPSI(W)R(M) framework was used to structure analysis of the literature and surface key environmental themes. Key drivers and activities established are the use of lagoon resources and expansion of lagoon settlements. The resultant identified pressures are waste, overuse of resources, and urban growth as well as climate change. Resultant stage changes are the degradation of water quality and ecosystems with impacts for the health of lagoon organisms and humans. Responses to changes were identified as a combination of punitive legislation, participatory management approaches and solutions focused on ecosystem restoration and engineering of the physical environment. Gaps identified include research on waste and aspects of climate change mitigation and adaptation. Also notable is a lack of multi- and interdisciplinary studies that address the inter-connecting stressors experienced at lagoons and studies of multiple lagoons. Studies also tend to be problem-focused with solutions rarely presented, limiting their applicability to inform management practices.

  • Rémi Thiéblemont , Gonéri le Cozannet , Jérémy Rohmer , Adrien Privat , Romain Guidez , Caterina Negulescu , Xénia Philippenko , Arjen Luijendijk , Floris Calkoen , Robert J. Nicholls

    Coastal erosion and flooding are projected to increase during the 21st century due to sea-level rise (SLR). To prevent adverse impacts of unmanaged coastal development, national organizations can apply a land protection policy, which consists of acquiring coastal land to avoid further development. Yet, these reserved areas remain exposed to flooding and erosion enhanced by SLR. Here, we quantify the exposure of the coastal land heritage portfolio of the French Conservatoire du littoral (Cdl). We find that 30% (~40%) of the Cdl lands owned (projected to be owned) are located below the contemporary highest tide level. Nearly 10% additional surface exposure is projected by 2100 under the high greenhouse gas emissions scenario (SSP5-8.5) and 2150 for the moderate scenario (SSP2-4.5). The increase in exposure is largest along the West Mediterranean coast of France. We also find that Cdl land exposure increases more rapidly for SLR in the range of 0–1 m than for SLR in the range 2–4 m. Thus, near-future uncertainty on SLR has the largest impact on Cdl land exposure evolution and related land acquisition planning. Concerning erosion, we find that nearly 1% of Cdl land could be lost in 2100 if observed historical trends continue. Adding the SLR effect could lead to more than 3% land loss. Our study confirms previous findings that Cdl needs to consider land losses due to SLR in its land acquisition strategy and start acquiring land farther from the coast.

  • Dongfeng Xie
  • Anagha Prasad , P. Rama Chandra Prasad , N. Srinivasa Rao

    Coastal waters are complex, dynamic, and sensitive, and any change in the system impacts the marine environment and life. Coastal water quality has been decreasing due to the incursion of anthropogenic derived waste and toxins into the ocean. This study investigates water quality along the Kollam coast of Kerala State, India, using Sentinel-2 Multispectral Imager (MSI) data for the period of 2019–2022. Four key water quality parameters, chlorophyll (Chl-a), total suspended matter (TSM), turbidity, and coloured dissolved organic matter (CDOM), were analysed for seasonal variations and driving factors. The study highlights the potential of web-based platforms like Google Earth Engine for facilitating large-scale water quality assessments. The results reveal a distinct seasonal pattern in all parameters, primarily influenced by monsoonal riverine discharge and anthropogenic activities as contributing factors to water quality degradation. Overall, the study emphasises the need for comprehensive monitoring and management strategies to ensure the long-term sustainability of the coastal ecosystem.

  • Hannah Sirianni , Burrell Montz , Sarah Pettyjohn

    Bluff landforms, sought-after for housing and development, present a hazard management challenge due to erosional processes despite the perceived safety of elevated land. This study focuses on the Neuse River Estuary in North Carolina, exploring coastal risk perception and erosion. A survey protocol was developed, and questionnaires targeted 246 residents with property within 100 m of the shoreline and 54 land use professionals in Craven County. To explore the connection of individual experiences with erosion, we use openly accessible LiDAR to quantify bluff retreat and erosion between 2014 and 2020, a period that encompasses Hurricane Florence in 2018. Our findings show: 1) survey results reveal a consensus among residents, with 90% observing alterations attributed to storm impacts, 2) preferences for addressing erosion lean towards structural measures, aligning with existing protection strategies (e.g., bulkheads, rip-rap) as opposed to nature-based solutions, 3) bluff tops are eroding at a higher median rate of -0.59 m per year, compared to -0.19 m per year for high sediment banks, and 4) an overall net volume decrease of approximately -1.89 cubic meters per year for Craven County, slightly more than the overall net loss for the Neuse River Estuary, which was -1.74 cubic meters per year. The findings underscore the need for a cohesive bluff erosion management plan, emphasizing the complexity of challenges and the importance of a holistic approach that combines technical studies with effective risk communication.

  • Z. B. Wang , Q. J. Lodder , I. H. Townend , Yonghui Zhu

    Future sediment transport from the North Sea coasts to the Dutch Wadden Sea for various future sea level scenarios has been studied because it influences the future sand nourishment demand for the maintenance of the coastline and because it determines bio-geomorphological development of the Wadden Sea. The present study focuses on two questions which have not yet been considered in the previous modelling studies using ASMITA: How will the transport develop around drowning of the intertidal flats in the Wadden Sea? How will tidal range change influence the future sediment exchange? By using SLR scenarios with faster acceleration and running the simulations for longer periods of time some inlets exhibited drowning, i.e., where the tidal flat volume vanishes. When drowning occurs, the sediment import rate approaches a maximum or a minimum, depending on the initial morphological state of the tidal inlet system. This maximum or minimum rate for a certain tidal inlet system depends on the SLR scenario. Theoretical analysis as well as modelling results show that tidal range change will influence the sediment import to the Wadden Sea. A tidal range increase will cause a decrease of the sediment demand in the Wadden Sea resulting into less sediment import to the Wadden Sea. It is thus important to study the tidal range development in the Wadden Sea by considering the interaction between SLR, tidal range change and morphological development in the system. It is further concluded that the empirical relation used in the previous studies is not representative of conditions in a tidal basin with fixed basin area, even though this relation has been derived from field observations in many tidal inlet systems worldwide. The equilibrium channel volume should be proportional to the tidal prism instead of to its 1.5th power.

  • Grethel García Bu Bucogen , Gabriel Eduardo Huck , María Cintia Piccolo , Vanesa Yael Bohn , Gerardo Miguel Eduardo Perillo

    The nonlinear interactions between river discharge, astronomical tidal wave, and local geomorphology during storm passage or water release from upstream dams can produce severe floods in the Río Negro lower basin (Argentina). For this reason, this paper aims to detect and study nonlinear processes in this area. The watercourse hydrodynamics was described using hourly water level data from three limnigraphs during 2003 – 2021 and flow time series. The tide gauge dataset was employed to describe the influence of tidal cycles on the hydrological regimen. Nonlinear processes' impact on the astronomical tidal cycle and river discharge was analyzed using Harmonic Analysis, and Fourier higher-order spectra, also it was complemented with the selection of two study cases. Harmonic Analysis results showed that the tidal wave entry upstream of the Río Negro modulates its hydrological regime, presenting the water column semidiurnal variations. Also, high-order spectral analysis detected nonlinear interactions in the signal in storm conditions with an energetic redistribution among the linear tidal constituents toward shallow water harmonics. Additionally, nonlinear interactions provoked a delay in the tidal ebb phase with a consequential extension of flooding duration time. This type of study contributes to the knowledge of the flood mechanisms activated during a storm.

  • Regina Asariotis , Isavela N. Monioudi , Viktoria Mohos Naray , Adonis F. Velegrakis , Michalis I. Vousdoukas , Lorenzo Mentaschi , Luc Feyen

    Seaports are critical for global trade and development but are at risk of climate change-driven damages, operational disruptions and delays with extensive related economic losses. The aim of the present contribution is to (a) provide an overview of the main impacts of climate variability and change (CV&C) on ports; (b) present recent research on trends and projections involving the main climatic factors/hazards affecting global ports; (c) provide an analytical overview of emerging international and regional policies and legislation relevant to port risk assessment and resilience-building under climate change; and (d) consider issues and areas for further action. As shown by projections under different climatic scenarios and timelines, many global ports will increasingly be exposed to significantly growing hazards under increasing CV&C, including extreme sea levels (ESLs), waves, and extreme heat events. Depending on scenario (RCP 4.5 and RCP 8.5) by 2050, 55% to 59% of the 3630 global ports considered could face ESLs in excess of 2 m above the baseline mean sea levels (mean of the 1980–2014 period); by 2100, between 71% and 83% of ports could face ESLs of this magnitude. Ports in most tropical/sub-tropical settings will face the baseline (mean of the 1976 – 2005 period) 1-in-100 year extreme heat every 1 – 5 years, whereas with 3 oC global warming, most global ports (except some in higher latitudes) could experience the baseline 1-in-100 years extreme heat event every 1 – 2 years. A range of policy and legal instruments to support climate change adaptation, resilience-building and disaster risk reduction have been agreed internationally as well as at regional levels. At the EU level, relevant legal obligations and related normative technical guidance aimed at ensuring the climate proofing of new infrastructure are already in place as a matter of supra-national law for 27 EU Member States. These could significantly enhance levels of climate-resilience and preparedness for ports within the EU, as well as for EU funded port projects in other countries, and may serve as useful examples of good practices for other countries. However, further action is needed to advance and accelerate the implementation of effective adaptation measures for ports across regions.

  • André Pardal , Ronaldo Adriano Christofoletti , Aline Sbizera Martinez

    Worldwide, coastlines have been replaced and altered by hard infrastructures to protect cities and accommodate human activities. In addition, human settlements are common and increasing in lowland areas threatened by coastal risk hazards. These urbanisation processes cause severe socioeconomic and ecological losses which demand policy reforms towards better coastal management and climate resilience. A first step in that direction is to comprehend the status of coastal hardening and occupation of vulnerable areas. Here, we mapped the coastline of the most populous and developed state of Brazil: São Paulo (SP). Our goal was to quantify the linear extent of natural habitats, artificial structures (AS), and occupations in low-elevation coastal zones (≤ 5 m) within 100 m from marine environments (LECZ100m) along the coastline and within estuaries. SP coast has a total extent of 244 km of AS, of which 125 and 119 km correspond to AS running along the coastline (e.g., seawalls, breakwaters) and extending from the shoreline into adjacent waters (e.g., jetties, pontoons, groynes), respectively. 63% of the total extent of AS is located in the most urbanised region. Breakwalls were the most common infrastructure (108 km), followed by jetties and wharves (~40 km each), and aquaculture and fishing apparatus (~24 km). Over 300 km of the SP coastline has inland occupations in LECZ100m: 235 and 67 km are adjacent to sandy beaches and estuarine/river margins, respectively. Coastal hardening is advanced in the central region of SP resulting from intense port activities and armoured shorelines. In other regions, much of coastal urbanisation seems to be driven by secondary usage of the cities, such as real estate development for beach houses and tourism. Our findings suggest that coastal urbanisation poses a major but often neglected source of environmental impact and risk hazards in SP and Brazil.

  • Umakanta Pradhan , Subrat Naik , Pravakar Mishra , Uma Sankar Panda , M. V. Ramana Murthy

    The present paper aimed to assess the sediment distribution pattern, mode of transport, and its interaction with hydrodynamic and topographic conditions at different depths and regions along the east coast of India. About 900 surficial sediment samples were collected and analysed on a monthly basis for the Chennai coastal region at 32 stations from 2013 to 2015. The study region is classified into four types, such as beach, inlet, 5 m, and 10 m depth. Sediment textural and grain size trend analyses were conducted to achieve the objectives. Sediment characteristics for the region were recorded as sandy, equally dominated by unimodal and bimodal at the beach, while unimodal at shallow depths (5 and 15 m). The sediments were medium sand to coarse sand at the beach, mostly fine followed by medium at 5 and 15 m depths. The sediment sorting is dominated by moderately well-sorted sediments; the skewness of beach sediments was negative, while nearshore sediments were found positive; average kurtosis values of sediments were noticed to be mesokurtic. The CM plot depicts that the sediments were mostly derived by tractive current, and the modes of transport are “bottom suspension and rolling” and “graded suspension no rolling” at beach locations and shallow water depths, respectively. The GSTA analysis reveals the annual average sediment transport pattern is northerly. The numerical hydrodynamic study confirms the GSTA and CM plot analysis. The study reveals a stable sedimentary environment south of the Chennai port and instability in the northern part. The study includes large spatiotemporal nearshore sediment data with hydrodynamic conditions, immensely helpful to coastal stakeholders and researchers.

  • Yufang Han , Bingke Dai , Hongwei Ding

    Since 1958, there have been significant changes in the Yangtze River estuary. Due to extensive reclamation and construction of ports and channels, the water area has drastically decreased, resulting in corresponding changes in hydrodynamics and riverbeds at the mouth of the river. According to the analysis of measured topographic data and Delft3D-FLOW model for seven typical historical periods since 1958 at the Yangtze River Estuary, this study investigates the characteristics of riverbed evolution and tidal flow dynamics. From 1958 to 2019, driven by strong human activities, the total area of the Yangtze River Estuary decreased from 2084 km2 to 1403 km2, with a decrease of 32.7%, while the total volume of the corresponding river channel changed slightly and remained stable. Compared with 1958, the volume of the Yangtze River Estuary in 2019 only increased by 345 million m3, with an increase of about 4.1%. The tidal dynamic change of the Yangtze Estuary is closely related to the riverbed evolution of each reach, which not only shapes the estuary landform, but also is affected by the riverbed evolution. Tidal level, tidal range and water area change are closely related. With the decrease of water area in the Yangtze River Estuary, tidal range tends to increase. Tidal prism change is closely related to channel volume. In the past 60 years, the tidal volume at the mouth of the Yangtze River has decreased by 8%. The research findings will provide technical support for enhancing flood control and tide resistance measures at the Yangtze River Estuary, as well as formulating comprehensive management plans for estuaries, contributing to the protection and sustainable development of the Yangtze River Estuary.

  • Bing Li , Hanmei Wang , Hang Tang

    Urban cover-collapse sinkholes pose a significant global challenge due to their destructive impacts. Previous studies have identified groundwater fluctuations, subsurface soil conditions, pipeline leakage, precipitation, and subterranean construction activities as key contributors to these phenomena. However, unique geological settings across different urban environments lead to variations in the primary factors influencing sinkhole formation. This study focuses on Shanghai, a city notable for its extensive urbanization and rich historical context, to explore the dynamics of sinkholes within urbanized areas worldwide. We employ spatial analysis and statistical methods to examine data on sinkholes recorded in the past two decades in Shanghai, correlating these events with the city’s shallow sand layer, ground elevation, and proximity to surface water. Our goal is to identify the dominant factors governing sinkhole occurrence in Shanghai and to lay the groundwork for their effective scientific management and prevention. Key findings indicate that most sinkholes in the area are associated with a thin shallow sand layer, low to moderate ground elevations, and the absence of nearby rivers. Additionally, many sinkholes correlate with subterranean voids within the confined aquifer beneath the cohesive soil layer. The lack of historical river channels, obscured by urban development, also indirectly contributes to sinkhole formation. We recommend enhancing urban river management and drainage systems to mitigate potential damage from water accumulation.

  • Qian Yu , Jianjun Jia , Shu Gao

    Green sea dykes, also known as ecosystem-based sea dykes, represent a novel type of coastal defense consisting of both traditional structural engineering and coastal ecosystems, designed to cope with the future trends of sea level rise and intensified storms. Here we focus on the mid-latitude mud coasts (eastern China in particular), which face the most prominent risks of storm surge, storm-induced giant waves, and shoreline erosion, and summarizes the scientific basis of green sea dykes and the current status of engineering practices. We show that the basic mechanisms of nearshore wave energy dissipation include bottom friction, sediment transport, and form drag. These explain the wave damping capacity of oyster reefs and salt marshes on mud coasts. In tidal flat environments, oyster growth increases frictional resistance and even causes wave breaking; the resuspension and transport of fine-grained sediments on salt marsh beds and the movement or resistance to hydrodynamic forcing of salt marsh vegetation stems effectively dissipate wave kinetic energy, and their efficiency increases with the elevation of the bed surface. Based on the wave damping capacity of oyster reefs and salt marshes on mud coasts, ecosystem-based sea dykes are being built in combination with traditional structured sea dykes. By utilizing natural tidal flats outside the dykes or implementing artificial modification projects, a certain scale of salt marshes and/or oyster reefs can be maintained, which serve to protect the sea dykes and enhance their wave resistance functions. From the perspective of system optimization, it is necessary to further improve the efficiency and sustainability of green sea dykes under constraints such as regional environment characteristics, ecosystem health, investment capacity, and ecological resilience. Related scientific issues include the theorization of the wave damping process of salt marshes, the niche and scale control of oyster reef and salt marsh ecosystems, the establishment of engineering standards and the design of the optimal form of sea dykes.

  • Arkar Myo , Oluwafemi Ajayi , Fei Huang , Yongxu Cheng , Jiayao Li

    In Myanmar, the advancement of the integrated rice-fish farming system legs behind rice monoculture farming, and there exists limited awareness of its advantages. Ecosystem services (ES) valuation plays a crucial role in integrated environmental decision-making, promoting sustainable agriculture practices, facilitating land-use planning, and ensuring food security in rural areas. Assessing the ES value in Delta region of Myanmar where rice-fish coculture is extensively practiced is essential for understanding the level of ES benefits derived from this farming system. The objective of this study is to promote the development of the rice-fish coculture system in delta region by estimating its ES value. We conducted a comprehensive examination of the Direct, Indirect, Option and Existence ES value of the rice-fish and rice monoculture in Maubin District, an area where rice-fish development research is being actively carried out within the delta region. The results revealed that the ES value of rice-fish coculture ecosystems in the study area was amounted to 28,588 US$/hm2/year. This value was 2.82% higher than rice monoculture system. Additionally, the rice-fish coculture system yielded product provisional values averaging 1,275 US$/hm2/year, representing a significant increase of 40.3% compared to rice monoculture farming. Our study shows that the adoption of rice-fish coculture farming system not only improves the ES value of the delta region, but also supports food security and socio-economic well-being. Furthermore, it provides valuable insights for policymakers on effective management policies for future development of the rice-fish coculture ecosystem.

  • Yi You Wong , Choon Weng Lee , Chui Wei Bong , Joon Hai Lim , Ching Ching Ng , Kumaran Narayanan , Edmund Ui Hang Sim , Ai-jun Wang

    Vibrio spp. is a group of heterotrophic bacteria that are ubiquitous in marine habitats, with various ecological and clinical importance. This study investigated the environmental factors that regulate Vibrio spp. dynamics in various tropical marine habitats, including nearshore (an estuary and a coastal beach) and offshore transects located northwest and southeast of Peninsular Malaysia, while focusing on the distribution of attached and free-living Vibrio spp., population growth, and community composition. The results showed that > 85% of the Vibrio spp. in nearshore waters occurred in attached form and correlated positively to total suspended solids (TSS) and Chlorophyll a (Chl a) concentrations. On the other hand, Vibrio spp. growth rates were positively correlated to dissolved organic carbon (DOC) concentrations, but negatively correlated to total bacterial counts, likely due to resource competition. In addition, high-throughput sequencing of 16S rRNA V3-V4 region showed that Vibrio spp. in these tropical waters contributed < 1 − 18% of the whole bacterioplankton community, and the six major Vibrio spp. taxa were V. alginolyticus group, V. brasiliensis, V. caribbeanicus, V. hepatarius group, V. splendidus group and V. thalassae. db-RDA (cumulative variance explicated = 93.53%) further revealed the influence of TSS, DOC, and dissolved organic nitrogen (DON) to the Vibrio spp. community profiles. The study highlighted the importance of suspended solids (TSS and Chl a) and dissolved organic nutrients (DOC and DON) towards Vibrio spp. dynamics in tropical marine waters.

  • Ahmet Durap

    Coastal regions worldwide face increasing threats from climate change-induced hazards, necessitating more accurate and comprehensive vulnerability assessment tools. This study introduces an innovative approach to coastal vulnerability assessment by integrating Bayesian Networks (BN) with the modern coastal vulnerability (CV) framework. The resulting BN-CV model was applied to Queensland's coastal regions, with a particular focus on tide-modified and tide-dominated beaches, which constitute over 85% of the studied area. The research methodology involved beach classification based on morphodynamic characteristics, spatial subdivision of Queensland's coast into 78 sections, and the application of the BN-CV model to analyze interactions between geomorphological features and oceanic dynamics. This approach achieved over 90% accuracy in correlating beach types with vulnerability factors, significantly outperforming traditional CVI applications. Key findings include the identification of vulnerability hotspots and the creation of detailed exposure and sensitivity maps for Gold Coast City, Redland City, Brisbane City, and the Sunshine Coast Regional area. The study revealed spatial variability in coastal vulnerability, providing crucial insights for targeted management strategies. The BN-CV model demonstrates superior precision and customization capabilities, offering a more nuanced understanding of coastal vulnerability in regions with diverse beach typologies. This research advocates for the adoption of the BN-CV approach to inform tailored coastal planning and management strategies, emphasizing the need for regular reassessments and sustained stakeholder engagement to build resilience against climate change impacts.

    Recommendations include prioritizing adaptive infrastructure in high-exposure areas like the Gold Coast, enhancing flood management in Brisbane, improving socio-economic adaptive capacity in Redland, and maintaining natural defences in Moreton Bay. This study contributes significantly to the field of coastal risk management, providing a robust tool for policymakers and coastal managers to develop more effective strategies for building coastal resilience in the face of climate change.

  • Aikaterini Karditsa , Serafeim E. Poulos

    Beaches play a pivotal role in supporting the socio-economic sector, particularly within the 'Sun, Sea, and Sand' (3S) tourism model. Valued for their ecosystem services, these coastal landforms are among the most dynamic and vulnerable environments, facing significant pressure from various climate challenges, which is further intensified by extensive anthropic exploitation. Their sustainable use is intrinsically linked to balancing the 3Ps: Planet, People, and Profit. To address the need for protection and sustainable utilization of coastal areas, the European Union has introduced the Protocol on Integrated Coastal Zone Management (ICZM) in the Mediterranean, specifically recommending in Article 8(2) the establishment of a setback buffer zone where permanent constructions are prohibited. This paper explores the application of risk mapping in the context of coastal setback policies, focusing on their effectiveness in managing beach retreat and adapting to climate change, particularly rising sea levels. The study examines selected beach areas in Peloponnese, Greece, influenced by various socio-economic factors. Through this analysis, the paper aims to contribute to the discourse on coastal management strategies that balance environmental sustainability with socio-economic benefits.

  • Anbuselvan Nagarajan , Senthil Nathan Dharmalingam , Vigneshwar Jeyasingh , Christinal Jayaseelan , Krishnan Vijayaprabhakaran

    The western Bay of Bengal is particularly susceptible to the harmful impacts of increasing coastal pollution, as coastal population and urban development are occurring at unprecedented rates. The rapid urbanization and industrialization along the east coast of India coupled with the transfer of contaminants into the Bay of Bengal through riverine systems, causing a direct impact on marine ecosystems. In the present study, an attempt has been made to understand the heavy metal distribution on shelf sediments in the western part of the Bay of Bengal to infer their source, processes, and historical changes in marine pollution. Three short sediment core samples were collected and analysed for sediment texture, organic matter, and heavy metals. Cores 1 and 2 contain a high amount of sand content, representing shallow marine with moderate to high-energy conditions, and were deposited at a recent time. Core 3 was dominated by muddy sand to sandy mud, which denotes calm sedimentation without any turbulence, and these sediments were deposited under relatively low-energy conditions. The higher concentration of organic matter in the top layers of the core indicates both marine and terrestrial input. The heavy metal contents show quite heterogeneous and variable distributions from one element to another and from one core to another. The calculated pollution indices such as Contamination Factor (CF), and Geoaccumulation Index (Igeo) and Pollution Load Index (PLI) values indicate that all the core sub-samples are severely enriched and highly polluted by Cd and moderately polluted by Pb. The increased heavy metal concentration in the upper portion of the sediment cores and moderate to considerable ecological risks indicate that these metals have been deposited in the study area for the past few decades.

  • Evgeniya Panchenko , Inna Krylenko , Andrei Alabyan

    The Pechora is the greatest river of the European Russian Arctic, flowing into the Barents Sea. Its estuarine area includes a vast delta, represented by extensive lowlands that are dissected by the complicated network of arms and branches. Despite the Pechora Delta is considered to be microtidal, tides with a range of 0.5–1 m during the low water period have a significant impact on the nature of currents in the main branches and the distribution of runoff among them during the tidal cycle. Tidal sea level fluctuations as well as storm surges determine the reversing pattern of currents over a significant extent of the delta branches. The modern field equipment combined with 2D hydrodynamic modeling has allowed to understand the contemporary flow features and evaluate their possible alterations under climate changes. The climate impact under considered scenarios is more pronounced during the low flow period, and this can lead to the propagation of tidal currents and an increase in water levels in the city of Naryan-Mar (100 km upstream from the mouth). From a flood risk perspective, sea level rise can be offset by a reduction in flood runoff.