Search Results (334)

Coral reef ecosystems of the Egyptian Red Sea face escalating pressure from compounding climate-driven warming and intensifying coastal development, dual stressors whose spatial expression and governance implications remained insufficiently characterized prior to the designation of the Great Fringing Reef Marine Protected Area under Prime Ministerial Decree No. 4419/2025. This study develops an integrated multi-decadal framework combining 32 years of sea surface temperature and surface current velocity records, two decades of satellite-derived chlorophyll-a observations, and four decades of satellite-derived coral reef extent mapping across five monitored coastal sites. Basin-wide SST warming of ≈1.15 °C is spatially heterogeneous, with the northern coastal sector warming nearly 25% above the southern sector rate. Surface circulation diverges structurally at Ras Banas: acceleration in the north is consistent with enhanced advective dilution of anthropogenic inputs, whereas consistent deceleration in the south (mean −0.03 m/s) is associated with an increased ecological footprint of wadi-derived sediment and nutrient discharge. Sharply localized chlorophyll-a anomalies, reaching 0.97 mg/m³ at Hurghada and spatially congruent with documented development chronologies, are consistent with anthropogenic disruption of oligotrophic water quality as an important contributor to reef degradation at northern sites. Field evidence from 2026 repeat surveys, interpreted alongside documented severe regional bleaching affecting southern Egyptian reefs during 2024, suggests that climate-driven thermal stress constitutes a parallel and active pressure, particularly in the southern sector where thermal and anthropogenic stressors appear to have converged during the period of most acute reef contraction. Landsat-derived losses of 24.1–50.2% across all monitored sites since 1985, including a 33.3% contraction at Halaib–Shalateen between 2022 and 2025 alone, reflect the cumulative outcome of these interacting pressures. These findings support the ecological necessity of the 2025 MPA while identifying spatially differentiated, dual-stressor governance priorities essential to translating its policy commitment into measurable conservation outcomes. Full article

Marine ecosystem degradation may reduce state revenues, increase recovery spending, and weaken fiscal sustainability, yet Indonesia does not yet have a routine governance mechanism that links marine natural capital valuation to fiscal-risk assessment in the State Budget Financial Note. This article develops a governance design, Blue Natural Capital Value at Risk (BNC-VaR), to translate changes in marine ecosystem conditions into fiscal-exposure signals for Indonesian public finance. Ecological condition indicators, such as fish-stock status, coral-reef condition, and mangrove extent, are converted into traceable valuation parameters and then into structured outputs, including fiscal-exposure scenarios, budget-relevance notes, and medium-term fiscal-sustainability readings across revenue, expenditure, deficit, and financing channels. The design treats ecological change as affecting the fiscal position through mediated and disclosable pathways rather than automatic causal effects. It adapts Value at Risk as a risk logic for public fiscal governance rather than as a conventional market-based probabilistic measure. Using theory synthesis and a model-paper approach across six analytical stages, the study produces five design principles, four formal propositions, and a five-component institutional architecture, with the Directorate General of State Assets Management positioned as a valuation custodian. As a conceptual contribution, BNC-VaR offers an operational architecture and implementation roadmap for future empirical testing in Indonesia and other archipelagic or marine-resource-dependent fiscal systems. Full article

There is a lack of information about the shark fisheries in Tamaulipas, a coastal state of the Gulf of Mexico, and the species that sustain them. This challenges the development of management and conservation strategies for this group. This study evaluates the ecological vulnerability of elasmobranch species under fishing pressure using a Productivity and Susceptibility Analysis (PSA). PSA was conducted using the literature biological data of the organisms caught in La Pesca, Tamaulipas, Mexico, and semi-structured surveys applied to artisanal fishers. Results indicate that eleven shark species and four ray species sustain this fishery, with biological productivity values ranging from 1.15 to 2.23 and susceptibility values from 1.91 to 2.09. The minimum ecological risk value was observed in Rhizoprionodon terranovae (v = 1.26), and the highest in Gymnura lessae (v = 2.14). Secondary, non-local biological productivity data limit the quality score but not the overall study validity, highlighting the need for primary regional data on Tamaulipas elasmobranchs. Our results rank elasmobranch species by ecological risk in La Pesca, Tamaulipas, helping policymakers prioritize species for research and conservation and determine whether current management matches local artisanal fishery realities or requires regional adjustments. Further regional studies are required to improve biological productivity data for elasmobranchs supporting artisanal fisheries in Tamaulipas. Full article

The Jabal Ali Marine Sanctuary, Dubai, is one of the most important marine protected areas (MPAs) in the UAE. The Arabian Gulf is characterised by extreme environmental conditions, including high temperatures and hypersaline waters. These conditions, combined with increasing anthropogenic pressures from coastal development projects such as desalination plants, energy plants and the Palm Jebel Ali development, may influence the pelagic ecosystems of MPAs. This study examined seasonal variability in phytoplankton communities and environmental conditions between summer (June 2017) and winter (December 2017), with particular emphasis on the interactions between temperature-driven stratification, hypersaline conditions, and phytoplankton community structure, abundance, and diversity. The AZTI (AZTI Tecnalia Marine Research Centre) Marine Biotic Index indicated predominantly “Good” to “High” ecological status of the pelagic ecosystem, indicating favourable environmental conditions. Potentially harmful algal bloom taxa, including Pseudo-nitzschia and Dinophysis, were detected at low abundances. Summer surveys recorded higher total species richness (44 vs. 34 species) and greater phytoplankton abundance (mean 68.6 vs. 49.8 cells/L) compared to those in winter. Diatoms dominated the assemblages in both seasons, accounting for 62–69% of the recorded species, while distinct spatial zonation patterns reflected habitat heterogeneity. The observed seasonal and spatial variability highlight the importance of incorporating temporal and spatial dimensions into management strategies. As the first pelagic phytoplankton assessment conducted in an MPA, this study provides important baseline data for understanding phytoplankton ecology in one of the world’s most environmentally extreme marine ecosystems. The findings contribute to evidence-based management under increasing climate change and anthropogenic pressures. However, because sampling was limited to the two principal climatic seasons, the study characterises inter-seasonal variability rather than a complete annual succession cycle. Additional surveys during spring and autumn are recommended to fully resolve seasonal succession dynamics. Overall, the findings support the continued protection of the sanctuary as an important biodiversity reservoir and a potential reference site for assessing marine ecosystem responses to environmental conditions. These findings are directly relevant to the environmental sustainability agenda of the Dubai 2040 Urban Master Plan, which prioritises the protection and expansion of the emirate’s nature reserves and the safeguarding of marine and coastal biodiversity. By establishing the first pelagic phytoplankton baseline for the sanctuary, this study provides an evidence base for monitoring and managing marine protected areas in line with this long-term framework. Full article

Large inland waterway infrastructure projects are increasingly exposed to supply disruptions, logistics uncertainty, carbon-control pressure, and dredged-material management challenges. Although resilient supplier selection, closed-loop supply chains, and ESG-oriented optimization have been widely studied, existing models rarely integrate resilient sourcing, hub configuration, forward material supply, reverse dredged-material resourceization, and social externality penalties within a unified maritime infrastructure decision framework. To fill this gap, this study proposes an ESG-endogenous closed-loop supply-chain optimization model for construction of an inland waterway navigation hub. The model jointly optimizes resilient supplier selection, transshipment/resourceization hub activation, equipment deployment, forward material flows, and reverse dredged-material flows. Three objectives are considered: minimizing economic cost, minimizing carbon emissions, and maximizing net social benefit. In particular, a social benefit and ecological-debt penalty function is introduced to quantify the transition from beneficial reuse to disposal-related negative externalities. NSGA-II is adopted as a multi-objective solver, with parameter calibration, convergence analysis, and benchmark comparison used to evaluate computational performance. The Pinglu Canal project is used as a case study. The results produce 14 Pareto-optimal solutions and show that the lowest-cost and lowest-emission configurations may still generate negative social benefits. A low-cost ESG transition region around 197.3–197.8 million CNY is identified, where limited additional investment can activate resourceization pathways and shift the system from ecological debt to near-saturated social benefit. These findings suggest that sustainable infrastructure planning should move beyond isolated cost or carbon minimization and instead identify balanced supplier–hub–equipment–flow configurations that jointly support resilience, circularity, and ESG performance. Full article

Plastic pollution has emerged as a critical global environmental challenge, driven by rising production, consumption, and inadequate waste management. Major plastic-consuming economies play a disproportionate role in global plastic leakage and therefore strongly influence international mitigation efforts. This review comparatively examines plastic policy frameworks in the European Union, the United States, China, India, and Japan to identify policy strengths, limitations, and transferable governance strategies. Due to the heterogeneous nature of the information sources, a narrative review methodology was employed, drawing on peer-reviewed literature, policy documents, institutional reports, and statistical datasets. Policy effectiveness was qualitatively evaluated using cross-comparable indicators, including per capita plastic consumption, waste generation, recycling rates, mismanaged waste, environmental leakage, and Extended Producer Responsibility (EPR) coverage. The analysis reveals substantial divergence in policy approaches: the EU demonstrates a comprehensive lifecycle-based framework with strong recycling performance and low leakage; China exhibits high enforcement capacity and effective upstream controls but faces scale-related challenges; the United States shows limited effectiveness due to fragmented governance and low recycling rates; India has robust regulatory intent but is constrained by high mismanaged waste and infrastructure gaps; and Japan achieves high downstream efficiency but relies heavily on thermal recycling with limited upstream reduction. The review highlights that effective plastic governance requires integrated lifecycle policies, strong enforcement, infrastructure investment, and international policy coordination rather than reliance on isolated downstream measures alone. Full article

Port decarbonization strategies often prioritize emissions under direct port authority control while overlooking dominant indirect sources. This study proposes an approach that combines Life-Cycle Assessment (LCA) and expert elicitation. While existing studies often rely on descriptive emission inventories, this paper demonstrates the value of combining quantitative life-cycle data with expert judgment. The methodology is applied to the Port of Sines, Portugal’s largest port by cargo volume and handling capacity. The LCA revealed that Scope 3 emissions account for over 99% of total greenhouse gas emissions, with ocean-going vessels as the main contributors. The expert elicitation process prioritized energy-related measures such as renewable energy, alternative fuels, electrification, and energy efficiency, while onshore power supply and ship–port interface measures received lower priority. By comparing the results, the study reveals a misalignment between the most significant emission sources (Scope 3 emissions, particularly ocean-going vessels) and commonly prioritized decarbonization measures (measures addressing Scopes 1 and 2). The main contribution lies in combining LCA findings and expert inputs to actively inform strategic decision making, helping ports realign decarbonization strategies toward high-impact measures and providing transferable insights for other ports pursuing net-zero objectives. Full article

This study provides the first comprehensive assessment of microplastic (MP) contamination within oyster bed ecosystems of the Kingdom of Bahrain. Sediment, water, and oyster samples were collected from six sites representing diverse environmental conditions. Raman spectroscopy identified the presence of 12 distinct polymer types, with polypropylene (PP), polyurethane (PU), poly(ethylene terephthalate)/diamine/multi-walled carbon nanotube (PET/diamine/MWCNT), and fluorinated ethylene propylene (FEP) being the most prevalent. MPs occurred predominantly as fragments, films, and pellets, with black being the most common color across all matrices. MP abundances ranged from 750 to 1850 MPs/kg dry weight in sediments, 2100–9600 MPs/L in water, and 1.78–5.25 MPs/individual in oysters, with particles (<50 µm) most frequent in oyster tissues. Although spatial variation was evident across regions, detected polymers included types associated with known ecotoxicological risks. No significant correlation was observed between sediment grain size and MP abundance, suggesting that additional hydrodynamic or anthropogenic factors may influence MP distribution. Overall, this study provides critical baseline data on MP contamination in Bahrain’s marine environments and highlights the need for continued monitoring to assess potential risks to marine ecosystems and seafood safety. It also contributes to the limited understanding of MPs in the Arabian Gulf, informing future monitoring, conservation and policy initiatives that support long-term environmental sustainability. Full article

Identifying and optimizing core factor configurations for anchorage operational safety under typhoon scenarios is critical to enhancing anchorage operational resilience and sustainable port development. This study develops a complementary hybrid SEM–fsQCA framework: key factors are identified via literature review and expert interviews; SEM quantifies factor correlations and contribution weights and corrects expert-evaluated anchorage capacity; six core factors are extracted, three typhoon types (heavy-rainfall, strong-wind, complex-track) are defined, and a coupled anchorage–typhoon case dataset is constructed. Subsequently, fsQCA performs necessary condition analysis and identifies causal configurations driving safety effectiveness. Based on these configurations, we establish a dynamic three-tier risk classification framework for refined anchorage management. Validated using 36 coupled cases (12 anchorages × 3 typhoon types) from Huizhou Port, a core hub in the Guangdong–Hong Kong–Macao Greater Bay Area, this framework enables adaptive vessel traffic scheduling throughout the entire typhoon cycle through dynamic tiered management. The proposed “identification-intervention-feedback” closed-loop governance model delivers theoretical rigor and operational implementation ability for coastal port typhoon risk mitigation. Full article

Given the increasing concern around greenhouse gas emissions and the decline in the availability of fossil fuels, there is increasing global demand to develop alternate fuels for maritime transportation that are sustainable and which have lower greenhouse gas emissions. Methanol is one such alternative fuel that has garnered considerable attention given its potential to be produced by more sustainable processes and its more favorable greenhouse gas emission profile in comparison with current fossil fuels. Understanding the physical and chemical properties of methanol under a range of conditions is essential for its development as a marine fuel. In this study, we seek to define physical and chemical properties of different methanol samples to simulate real-world storage conditions as these data are lacking in the literature. Several methanol samples were evaluated: nearly pure methanol; International Organization for Standardization (ISO) marine methanol (MM) grades A, B, and C; and methanol plus higher alcohols. We first evaluated all methanol samples for impurities, acetic acid content, density, and distillation range. We then characterized the effects of water absorption and found that methanol can easily absorb unacceptable water content from humid air within hours, necessitating storage conditions that prevent this process. In eight-week aging experiments at 20 °C and 40 °C in ambient air, we did not observe significant oxidation for any of the methanol samples; however, we did observe increases in acid number. We assessed the impact of contamination of methanol with water, marine gas oil (MGO), and an MGO–biodiesel mixture on density, viscosity, distillation range, and lubricity. Finally, we show that MGO contamination of methanol results in a slight increase in sooting tendency. In aggregate, our results provide an in-depth analysis of physical and chemical properties of methanol as well as the impacts of storage conditions and impurities on the properties of fuel methanol. Full article

The use of bait in Vietnamese gillnet fisheries to improve fishing efficiency has recently increased, yet its influence on both target species and protected bycatch species is unknown. This study compared the catching performance of baited versus non-baited drift gillnets in a pelagic fishery off central Vietnam to evaluate whether bait can increase catch rates of commercially important species and protected species. Sea trials were conducted during the stewardship fishery using identical gillnets, differing only in the presence of bait bags containing round scad (Decapterus macrosoma). The results showed that baited gillnets significantly increased CPUE of most target species, including skipjack tuna (Katsuwonus pelamis) at 68.2%, frigate tuna (Auxis thazard thazard) at 55%, and bullet tuna (Auxis rochei) at 62.4%, compared to conventional gillnets. Wahoo (Acanthocybium solandri) and mahi mahi (Coryphaena hippurus) also increased by 50.6% and 51.6%, respectively; however, these increases were not statistically significant. Length-based analyses indicated that baited and non-baited gillnets differed in size-dependent catch efficiency, with certain length classes showing significantly higher or lower capture probabilities depending on the species. Notably, baited gillnets also showed a higher likelihood of capturing hammerhead sharks (Sphyrna spp.). These results show that baiting can improve the fishing efficiency in pelagic gillnet fisheries, potentially gaining economic performance. However, the increased interaction with protected species highlights a critical trade-off, underscoring the need for bycatch mitigation measures and management strategies to ensure that improvements in fishing efficiency remain aligned with the principles of sustainable fisheries and long-term ecosystem conservation. Full article

Polyethylene terephthalate (PET) is among the most used plastics in domestic and industrial applications, particularly packaging, food containers and textiles. However, its recalcitrance to decomposition and biodegradation mostly results in landfilling and accumulation of PET waste in the environment if not processed. Chemical recycling of PET via selective depolymerization into its monomers may represent a pivotal step in the development of a truly circular economy of PET, which is still limited by economic and environmental sustainability issues. In this work, the depolymerization of PET is reported using ZnO as an insoluble catalyst, and ethanol as both a lytic agent and green solvent. A detailed investigation of reaction parameters, including reaction temperature, time and catalyst loading, showed that complete conversion of PET to diethyl terephthalate (DET) can be achieved with 92.5% selectivity at 180 °C and 48 h, with the potential for full DET selectivity at longer reaction times. The solid catalyst could be recovered and reused by simple centrifugation, with no loss of conversion or selectivity over three consecutive reuses. Full article

Hyper-arid marine ecosystems, characterized by extreme environmental conditions, are experiencing intensified stress from the synergistic effects of climate change and pollution. This review synthesizes current knowledge on these interactions in Qatar’s coastal waters, serving as a model system for the Arabian Gulf. We document significant accumulations of heavy metals, petroleum hydrocarbons, microplastics, and emerging contaminants near urban and industrial zones. The region’s rapid warming, hypersalinity, and restricted circulation amplify pollutant toxicity through mechanisms such as increased bioavailability, oxidative stress, and impaired physiological responses. These synergies elevate mortality in sensitive species by 50–100% compared to single stressors, push organisms beyond their physiological limits, and trigger biodiversity loss. As an example, given a baseline of around USD 148 million, a 30% decrease in exploitable fish biomass might result in an annual loss of approximately USD 45 million in the value of Qatar’s fisheries and aquaculture industry. Despite growing evidence, critical gaps persist in understanding mixture toxicity under Gulf-specific extremes, endocrine and neurobehavioral endpoints, and quantitative ecosystem service valuations. We conclude by highlighting emerging solutions, including IoT-based monitoring, AI-driven forecasting, and nature-based remediation, as pathways to enhance resilience under accelerating environmental change. These findings have important implications for marine ecosystem sustainability, food security, and sustainable coastal management in Qatar and other hyper-arid regions. This synthesis establishes Qatar’s coastal ecosystem as a global model for understanding climate–pollution feedback in hyper-arid seas. Full article

In the context of occupational environments and sustainable employment, this review explores the effects of declining workers’ health, environmental degradation, and the depletion of marine resources on workers’ psychological well-being. As seas and oceans are increasingly exploited and used as dumping sites for both solid and liquid waste, marine ecosystems are severely degraded, with negative impacts on biodiversity, water quality, and ecosystem processes. Marine biodiversity is crucial to maintaining global food security and supporting the livelihoods of millions of people worldwide. Moreover, this study examines the role of digital technology in the marine industry in safeguarding workers’ sustainable well-being. It emphasizes the complementary roles of law and technology in promoting it. The risks to the health and well-being of marine workers are greatly increased by the occupational consequences of climate change on the sustainable environment and the effects of working in marine environments. Working conditions, incomes, and even unemployment among marine workers have been directly affected by the degradation of marine environments and the depletion of marine resources. Anxiety, panic, depression, rage, and other unpleasant emotions that affect workers’ health and pose mental health risks are detrimental to the psychological well-being of marine workers. The challenges of employment in the marine industry adversely affect the physical and mental well-being of marine employees and hinder economic growth. However, digital technology in marine environments has fundamentally altered the regulations governing marine operations. Full article

The rapid diffusion of industry 4.0 technologies has substantially transformed the maritime transportation sectors by enabling data-driven operations, enhanced connectivity, and more intelligent decision-making processes. Digital technologies such as the Internet of Things (IoT), simulation systems, and advanced data analytics are increasingly reshaping operational structures in maritime logistics, positioning technological transformation as a strategic priority for firms. However, the weighting and prioritization of components emerging with industry 4.0 technologies remain an underexplored area in the literature. The primary motivation of this study is to determine the weights of these industry 4.0 components using the Bayesian Best Worst Method (BWM) and to reveal their corresponding credal ranking levels. In this context, the present study aims to evaluate and prioritize the critical industry 4.0 components influencing technological transformation processes using the Bayesian BWM. Bayesian BWM is preferred over alternative Multi Criteria Decision Making (MCDM) approaches due to its ability to explicitly model uncertainty within a probabilistic framework, generate more consistent weighting results, and flexibly incorporate decision-makers’ judgments. The findings reveal that safety and security (0.2945) constitute the most influential main component, underscoring the necessity of robust digital infrastructures and reliable systems within highly digitalized operational environments. Among the sub-components, data privacy (0.1301) demonstrates the highest global weight, highlighting the growing importance of safeguarding sensitive information in data-intensive digital systems. The results further indicate that autonomous operation and coordination play significant roles in facilitating efficient digital operations, particularly through real-time equipment monitoring and IoT-based operational visibility. Moreover, sustainability (0.1968) emerges as the second most important component, suggesting that organizations increasingly assess technological investments not only in terms of operational efficiency but also with respect to long-term resilience. Within this dimension, continuous training (0.0614) is identified as the most influential component, indicating that the success of digital transformation depends not only on technological infrastructure but also on the development of human capabilities. With the increasing digitalization of the maritime industry, protection against cyber threats has become essential for ensuring operational continuity and safeguarding data integrity. In this regard, adopting proactive cybersecurity strategies and continuously monitoring and updating systems are of critical importance. In the digital transformation of maritime transportation, integrating sustainability considerations is essential to ensure long-term operational efficiency and environmental responsibility. These practical implications are particularly relevant for policymakers, port authorities, and shipping companies seeking to enhance both digital capabilities and sustainable performance. Full article