Search Results (46)

Typhoons can significantly alter ocean hydrodynamic processes through their powerful external forces, greatly affecting marine biogeochemistry and ocean productivity. However, the specific impacts of typhoons with different tracks on coastal dynamics, including frontal activities and phytoplankton lateral transport, are not well understood. This study captured two distinct types of typhoons, namely Merbok (2017) and Nuri (2020), which landed from the right and left sides of the Pearl River Estuary (PRE), respectively, utilizing satellite remote sensing data to study their impacts on frontal dynamics and marine productivity. We found that after both typhoons, the southwest monsoon amplified geostrophic currents significantly (increased ~14% after Nuri (2020) and 48% after Merbok (2020)). These stronger currents transported warmer offshore seawater from the South China Sea to the PRE and intensified the frontal activities in nearshore PRE (increased ~47% after Nuri (2020) and ~2.5 times after Merbok (2020)). The ocean fronts limited the transport of high-chlorophyll and eutrophic water from the PRE to the offshore waters due to the barrier effect of the front. This resulted in a sharp drop in chlorophyll concentrations in the offshore-adjacent waters of PER after Typhoon Nuri (2020) (~37%). By contrast, despite the intensified geostrophic current induced by the summer monsoon following Typhoon Merbok (2020), its stronger offshore force, driven by the intense offshore wind stress (characteristic of the left-side typhoon), caused the nearshore front to move offshore. The displacement of fronts lifted the restriction of the front barrier and led more high-chlorophyll (increased ~4 times) and eutrophic water to be transported offshore, thereby stimulating offshore algal blooms. Our findings elucidate the mechanisms by which different track typhoons influence chlorophyll distribution through changes in frontal dynamics, offering new perspectives on the coastal ecological impacts of typhoons and further studies for typhoon impact modeling or longshore management. Full article

Microplastic pollution presents a significant and rising risk to both ecological integrity and the long-term viability of economic activities reliant on marine ecosystems. The Black Sea, a region sustaining economic sectors such as fisheries, tourism, and maritime transport, is increasingly vulnerable to this form of contamination. Mytilus galloprovincialis, a well-established bioindicator, accumulates microplastics, providing a direct measure of environmental pollution and indicating potential economic consequences deriving from degraded ecosystem services. While previous studies have documented microplastic pollution in the Black Sea, our paper specifically quantified microplastic contamination in M. galloprovincialis collected from four sites along the western Black Sea coast, each characterised by distinct levels of anthropogenic influence: Midia Port, Constanta Port, Mangalia Port, and 2 Mai. We used statistical analysis to quantify site-specific microplastic contamination in M. galloprovincialis and employed machine learning to develop models predicting accumulation patterns based on environmental variables. Our findings demonstrate the efficacy of mussels as bioindicators of marine plastic pollution and highlight the utility of machine learning in developing effective predictive tools for monitoring and managing marine litter contamination in marine environments, thereby contributing to sustainable economic practices. Full article

Nuclear accident-derived radionuclide dispersion poses critical challenges to marine ecological sustainability and human–ocean interdependence. While existing studies focus on hydrodynamic modeling of pollutant transport, the link between nuclear safety and sustainable ocean governance remains underexplored. This study investigates radionuclide diffusion patterns in semi-enclosed bays using a high-resolution coupled hydrodynamic particle-tracking model, explicitly addressing threats to marine ecosystem stability and coastal socioeconomic resilience. Simulations revealed that tidal oscillations and topographic constraints prolong pollutant retention by 40% compared to open seas, elevating local concentration peaks by 2–3× and intensifying bioaccumulation risks in benthic organisms. These findings directly inform sustainable marine resource management: the identified high-risk zones enable targeted monitoring of fishery resources, while diffusion pathways guide coastal zoning policies to decouple economic activities from contamination hotspots. Compared to Fukushima’s open-ocean dispersion models, our framework uniquely quantifies how semi-enclosed geomorphology exacerbates localized ecological degradation, providing actionable metrics for balancing nuclear energy development with UN Sustainable Development Goals (SDGs) 14 and 3. By integrating hydrodynamic specificity with ecosystem vulnerability thresholds, this work advances science-based protocols for sustainable nuclear facility siting and marine spatial planning. Full article

The Yangtze River Basin (YRB) is an important source of marine microplastics (MPs). However, unscientific research methods in previous studies have led to inaccurate estimates of the occurrence and ecologic risk of MPs. This study aimed to comprehensively assess the distribution and ecological risks of MPs in the YRB, through investigating the occurrence of full-size MPs in the surface waters of the YRB over 3 years. The Size Effect was developed based on the impact of size and MP-carried pollutants on human health, and combined with multiple methods to evaluate the potential risks of MPs. The average MP abundance in the YRB was 8797 ± 12,281 items/m³, dominated by polypropylene and fragments. The small MPs (<0.3 mm; 92.52%) were the driving factor of the MP spatial heterogeneity. Interestingly, the Three Gorges Dam significantly altered the MP distribution and weakened the MP transportation. Agricultural activities, wastewater treatment plants, and atmospheric deposition were the main sources of MPs in the YRB. Multiple ecological risk assessment indicated that the MP risk in the YRB was at the middle–low level. This study addresses the occurrence of <0.05 mm MPs in the YRB, provides insights for MP risk assessment, and serves as a reference for sustainable management. Full article

The Brazilian Amazon has one of the largest river networks in the world, connecting riverine communities, many of which have no roadways. The use of high-speed vessels, including those that are locally made, is necessary for the transportation of people to perform their day-to-day activities. However, regional news and social media data have shown that these vessels are involved in accidents. This work describes some of the key challenges to improving the sustainability and safety of regional high-speed vessels. Field research was performed in the state of Amazonas to document regional vessels and provide graphic evidence of the possible risk factors that could cause accidents as the path to prevent them. Some risk mitigation alternatives were discussed. Cameras and a drone were used to capture information either from the shore or from small boats. The main challenges are related to the adequate management of seasonal changes in river depths; wave and wind behavior; wave wash effects; the interaction of vessels with rocks, sand banks, mud, and vegetation; embarkation and disembarkation activities; the monitoring and regulation of safety requirements and dangerous operations; and the slowness in implementing technological advances that would improve vessels’ safety. It is hoped that the work in this paper will contribute to improving the sustainability of marine activities in the Amazon and similar regions worldwide. Full article

Since the Industrial Revolution, underwater soundscapes have become more complex and contaminated due to increased cumulative human activities. Anthropogenic underwater sources have been growing in number, and shipping noise has become the primary source of chronic acoustic exposure. However, global data on current and historic noise levels is lacking. Here, using the Listening to the Deep-Ocean Environment network, we investigated the baseline shipping noise levels in thirteen observatories (eight stations from ONC Canada, four from the JAMSTEC network, and OBSEA in the Mediterranean Sea) and, in five of them, animal presence. Our main results show yearly noise variability in the studied locations that is not dominated by marine traffic but by natural and biological patterns. The halt in transportation due to COVID was insignificant when the data were recorded far from shipping routes. In order to better design a legislative framework for mitigating noise impacts, we highlight the importance of using tools that allow for long-term acoustic monitoring, automated detection of sounds, and big data handling and management. Full article

Due to the increasing impact of climate change and human activities on marine ecosystems, there is an urgent need to study marine water quality. The use of remote sensing for water quality inversion offers a precise, timely, and comprehensive way to evaluate the present state and future trajectories of water quality. In this paper, a remote sensing inversion model utilizing machine learning was developed to evaluate water quality variations in the Ma’an Archipelago Marine Special Protected Area (MMSPA) over a long-time series of Landsat images. The concentrations of chlorophyll-a (Chl-a), phosphate, and dissolved inorganic nitrogen (DIN) in the sea area from 2002 to 2022 were inverted and analyzed. The spatial and temporal characteristics of these variations were investigated. The results indicated that the random forest model could reliably predict Chl-a, phosphate, and DIN concentrations in the MMSPA. Specifically, the inversion results for Chl-a showed the coefficient of determination (R²) of 0.741, the root mean square error (RMSE) of 3.376 μg/L, and the mean absolute percentage error (MAPE) of 16.219%. Regarding spatial distribution, the concentrations of these parameters were notably elevated in the nearshore zones, especially in the northwest, contrasted with lower concentrations in the offshore and southeast areas. Predominantly, the nearshore regions with higher concentrations were in proximity to the aquaculture zones. Additionally, nutrients originating from land sources, transported via rivers such as the Yangtze River, as well as influenced by human activities, have shaped this nutrient distribution. Over the long term, the water quality in the MMSPA has shown considerable interannual fluctuations during the past two decades. As a sanctuary, preserving superior water quality and a healthy ecosystem is very important. Efforts in protection, restoration, and management will demand considerable labor. Remote sensing has demonstrated its worth as a proficient technology for real-time monitoring, capable of supporting the sustainable exploitation of marine resources and the safeguarding of the marine ecological environment. Full article

Nanoplastics, as emerging environmental pollutants, can transport contaminants across marine environments, polluting pristine ecosystems and being ingested by marine organisms. This transfer poses a severe threat to global aquatic ecosystems and potentially impacts human health through the food chain. Neurobehavioral and reproductive toxicity are critical areas of concern because they directly affect the survival, health, and population dynamics of aquatic species, which can have cascading effects on the entire ecosystem. Using zebrafish as a model organism, we investigated the toxic effects of environmental concentrations of polystyrene nanoplastics (PS-NPs). Behavioral assessments, including the novel tank test and open field test, demonstrated significant neurobehavioral changes, indicating increased anxiety and depressive behaviors. A pathological analysis of brain and gonadal tissues, along with evaluations of neurobehavioral and reproductive toxicity biomarkers, revealed that exposure to PS-NPs leads to brain tissue lesions, inflammatory responses, oxidative stress activation, hormone level disruptions, and gonadal damage. Real-time quantitative PCR studies of reproductive gene expression further showed that PS-NPs disrupt the endocrine regulation pathways of the brain-pituitary-gonadal (BPG) axis, causing reproductive toxicity with sex-specific differences. These findings provide crucial insights into the impacts of nanoplastics on aquatic organisms and their ecological risks, offering theoretical support for future environmental protection and pollutant management efforts. Full article

Fishing is an essential economic activity and source of livelihood for millions of people worldwide. However, overfishing and unsustainable practices have led to a decline in fish populations and the degradation of marine ecosystems. Moreover, fishing activities can contribute to climate change through the emission of greenhouse gases (e.g., carbon dioxide and methane) from fishing vessels and seafood transportation. To mitigate the environmental impacts of fishing activities, sustainable fishing practices must be implemented to minimize the negative impacts of fishing on the environment while maintaining the productivity and diversity of fish populations and ecosystems. These practices include using selective fishing gear, avoiding fishing in vulnerable habitats, implementing fishery management plans, and reducing the carbon footprint of the fishing industry. To this end, and as a first step in defining efficient and effective measures towards the sustainability of capture fishing activity, an analysis of the environmental sustainability of the Galician fishing sector, one of the main European regions in this field, is presented in this work. An ecosystem-based indicator (ecological footprint, calculated by adding the so-called fishing ground footprint and the carbon footprint) was employed to quantify the main impacts of capture fishing during extractive activity. The catch composition and fuel consumption of the fleet based on the vessels’ power, and economic benefits, were the parameters used in this analysis. The results showed that ports with larger vessels and fleets seem to be more eco-efficient than those concentrating smaller vessels in targeting lower trophic level species. Full article

This paper provides a review of toxic algal blooms in the Philippine and Malaysian coastal and marine systems, considering relevant available knowledge, including climate change dimension/s in the assessment of their recorded recent expansion. The first record of human toxicity in the Philippines associated with HABs/toxic algal blooms specifically was during the bloom of Pyrodinium bahamense in the Sorsogon, Samar, and Leyte waters in 1983. Since then, the species has been identified to occur and cause blooms in about 44 sites/areas in the country. Recent government reports, i.e., 2021, 2022, and 2023, have also identified other paralytic shellfish poisoning (PSP) causative organisms (Gymnodinium catenatum, Alexandrium spp.) in the country. New records indicate that the presence of PSP causative species has been reported almost year-round in the Philippines. In Malaysia, PSP caused by P. bahamense was initially confined in 1981 to the state of Sabah, Malaysia Borneo, but since then, blooms of this species have been reported almost annually at different scales across the coastal waters of Sabah. P. bahamense and other cyst-forming dinoflagellates could be transported naturally or through human activities. Other eco-physiological and environment factors from the field and the laboratory have been used to study the bloom dynamics and transport of PSP causative species in several areas in the Philippines and Malaysia. More recently, plastics and other marine litter have been considered potential vectors of invasion/transport or expansion of dinoflagellates with other microorganisms. ENSO events have been observed to be stronger since 1950 compared with those recorded from 1850 to 1950. The extreme phases of the ENSO phenomenon have a strong modulating effect based on seasonal rainfall in the Philippines, with extreme ENSO warm events (El Niño) often associated with drought and stresses on water resources and agriculture/aquaculture. In contrast, cold events (La Niña) often result in excessive rainfall. The La Nina Advisories from 2021 to 2023 (18 advisories) showed the persistence of this part of ENSO, particularly in regions with recurrent and new records of HABs/toxic algal blooms. More studies and monitoring of another type of toxic algal bloom, Ciguatera Fish Poisoning (CFP), are recommended in tropical countries such as the Philippines and Malaysia, which have extensive reef areas that harvest and culture marine fish for local and export purposes, as accelerating reports of this type of poisoning have apparently increased and causative organisms have been identified in several areas. There is an urgent need to enhance HAB/toxic algal bloom research and monitoring, particularly those related to climate change, which has apparently impacted these blooms/occurrences directly or indirectly. Local researchers and managers should be made aware of the knowledge and tools already available for their utilization and enhancement to meet local conditions and challenges for potential recurrence and expansion of HABs/toxic algal blooms. Regional and international HAB research and collaboration should be further advanced for the protection of public health and marine resources. Full article

Maritime transport, responsible for delivering over eighty percent of the world’s goods, is the backbone of the global delivery industry. However, it also presents considerable environmental risks, particularly regarding aquatic contamination. Nearly ninety percent of marine oil spills near shores are attributed to human activities, highlighting the urgent need for continuous and effective surveillance. To address this pressing issue, this paper introduces a novel technique named OS-BREEZE. This method employs an Unmanned Surface Vehicle (USV) for assessing the extent of oil pollution on the sea surface. The OS-BREEZE algorithm directs the USV along the spill edge, facilitating rapid and accurate assessment of the contaminated area. The key contribution of this paper is the development of this novel approach for monitoring and managing marine pollution, which significantly reduces the path length required for mapping and estimating the size of the contaminated area. Furthermore, this paper presents a scale model experiment executed at the Coastal and Marine Engineering Research Institute (CAMERI). This experiment demonstrated the method’s enhanced speed and efficiency compared to traditional monitoring techniques. The experiment was methodically conducted across four distinct scenarios: the initial and advanced stages of an oil spill at the outer anchoring, as well as scenarios at the inner docking on both the stern and port sides. Full article

This study investigates the impact of varying environmental conditions on the metal composition within the tissues of Sparisoma cretense, contributing to the understanding necessary to offer scientifically sound advice regarding the health status of this species. This knowledge extends beyond fishery production, encompassing implications for food security. The data span the years 2022 and 2023, encompassing both cold and warm climatic seasons. The concentrations of various metals, such as Al, Zn, Cd, Pb, Fe, and Cu, exhibited noteworthy variations across the islands, with significant increases recorded in 2023, particularly during the warm season. The intricate interplay between multiple factors shaped the availability of the analyzed elements in S. cretense. Factors such as rising temperatures during the warm season increased biological activity in marine ecosystems, seasonal fluctuations in weather conditions, water quality, and anthropogenic influences, all contributing to the observed variations in metal concentrations. Additionally, the geological composition of each island and the patterns of marine currents and sediment transport play pivotal roles in these differences. Comprehensive scientific research, monitoring, and environmental surveillance are essential for a holistic understanding of this variability and providing valuable insights for the conservation and management of marine ecosystems in the Canary archipelago. Full article

Marine container terminals play an irreplaceable role in modern logistics. They ensure the functioning of material flows and supply chains. Optimal and efficient operations of terminals are increasingly based on full or partial automation. As a result, the expertise and skill prerequisites for service personnel and managers are increasing. This paper presents an original idea of creating a “profession simulator”. Its principle is based on the application of a dynamic computer simulation method. The results represent a generally valid concept for a “profession simulator” that can be calibrated for any container terminal. Within this concept, the inputs, outputs, and processes that take place in the profession simulator are defined. The simulation model is created with the Tecnomatix Plant Simulation program. Mathematical models are implemented for all individual processes in the simulation model. A programming method using the SimTalk 2.0 language is used for their implementation. The obtained results point to the possibility of using the profession simulator to analyze and monitor selected indicators regarding handling techniques, the utilization of maritime terminals, information about the number of transported containers, or the implementation of handling activities. Full article

In this study, we developed a transport model for typical pollutants in the Yellow Sea using the Lagrangian particle tracking method to analyze the trajectories of fish feed, a common pollutant in the Yellow Sea. The model incorporates the influence of ocean currents and surface winds on pollutant transport and utilizes a series of numerical experiments to simulate pollutant transport. Through statistical analysis of the numerical experiment results, we identified characteristic circles that represent the pollutant distribution patterns. Furthermore, based on the current and wind information within these characteristic circles, we derived an empirical formula to describe pollutant distribution. This formula enables us to predict the spatial distribution of pollutants using available current and wind data. Using this empirical formula, we designed an effective path to avoid pollutant contamination. This approach not only optimizes the utilization of computational resources within the study area but also contributes to the rational planning of navigation routes for aquaculture vessels. Overall, our study provides valuable insights into the transport behavior of fish feed pollutants in the Yellow Sea. The establishment of the empirical formula and the design of effective routes to avoid pollution contribute to the efficient management of pollution and facilitate the planning of marine activities in the region. Full article

Although the Brazilian Amazon is still one of the most well-conserved environments in the world, it contains an extensive network of waterways that are used by a wide range of vessels that transport both people and cargo, as well as undertaking other activities. To plan environmental risk disaster strategies here, the potential effects of technological disasters, including marine accidents, must be taken into consideration. This paper seeks to redress this by providing a review of the possible risks to the Amazon aquatic environment that could result from various types of marine accidents. While the Amazon region has been researched worldwide, both extensively and intensively, regarding land use, climate, and environmental characterization, work in this field is scarce. A review of the main environmental characteristics of the Amazon is provided, including a description of common marine accidents that have occurred in this region. The environmental impacts experienced by the aquatic environment due to marine accidents worldwide were reviewed from the scientific literature to examine potential risks to the Amazon waterways. It was found that marine accidents, such as fire/explosions and the sinking of ships with different types of cargo, can cause the spillage of oil and other hazardous materials, causing catastrophic damage to the aquatic environment. Changes in the hydrological characteristics of rivers, including unexpected changes in the weather, such as heavy rain and winds, may also influence pollutant dispersion. Initiatives to deal with these technological hazards in the Amazon basin should also consider the potential social and environmental impacts in the protected areas of this region. It is hoped that this paper can serve as a starting point toward the governance and planning of risk disaster management actions, which are aimed at reducing the negative environmental impacts caused by marine accidents in the region. Full article