Marine Pollution Research Articles

Implementasi UNCLOS 1982 dalam Mengatasi Pencemaran Laut oleh Pemerintah Indonesia: Studi Kasus Pencemaran Minyak di Wilayah Perbatasan Kabupaten Bintan

There are several issues that should be the focus of the Indonesian and international governments, including marine pollution in the Bintan area. Indonesia's marine environment has various types of natural resources, both biotic and abiotic natural resources, as well as very important resources such as means of communication, recreational media, trade and transportation routes. Therefore, we need to think about how we can overcome these hazards in the future. Various events that have occurred so far in Indonesia, especially in the border area of Bintan Regency, highlight the role of the Indonesian government in protecting Indonesia's maritime areas from various risks of loss and emphasizing the management of natural resources in an orderly and appropriate manner. Therefore, this study was conducted to analyze the strategies and efforts made by the government by implementing UNCLOS 1982 against oil pollution that often occurs in the border area of Bintan Regency.

Energy-efficient eco-friendly marine waste treatment: Recovery of caprolactam from fishing net waste using seashell-derived catalyst

Fishing net waste (FNW) is marine waste having significantly negative effects on the marine environment and ultimately human health. Herein, we endeavored to use a catalyst made from seashells for the recovery of caprolactam (CPL) from FNW (made of polyamide 6; free of any other materials like floats, lead lines, and sand) via a catalytic pyrolysis under CO2 atmosphere. The catalytic pyrolysis of FNW in CO2 over the seashell-derived catalyst yielded 77.7 wt% CPL at 500 °C. It was simulated on a large-scale based on data from laboratory-scale experiments, and energy analysis and life-cycle assessment (LCA) were carried out. The proposed integrated process consists of three steps: FNW-to-CPL conversion via catalytic pyrolysis, CPL recovery, and heat and power production. An effective separation process consisting of in series of flash and distillation columns was designed by considering the characteristics of resulting mixture, and the overall process allows the production of CPL from FNW with a high yield (74.3 %). This value is only 3.4 % point lower than the experimental yield of CPL (77.7 %), and the energy requirements (0.21 MW heating energy) are met internally. The results of the LCA suggest that the proposed strategy can help solve the problem of marine pollution from debris such as FNW.

Indoor laboratory experiments for beach litter spectroradiometric analyses

Marine pollution is a growing global issue, impacting both marine ecosystem and human health. High quantities of debris, mainly composed by plastic items, have been identified both in the coastal area and in the sea environment. Remote sensing techniques represent an useful tool (complementary to the in-situ campaigns) to monitor litter in the coastal environment, especially if the spectral signatures of the debris are known. In this framework, harvested beach litter (plastic items especially) were collected from two sandy beaches. The samples were spectrally characterised by implementing two indoor laboratory experiments with the aim to infer the best wavelengths to be used for beach litter detection via the spectral angle mapper index. Due to lack of a scientific protocol concerning the spectral data acquisition, two experimental setups were carried out to simulate the direct and diffuse illumination conditions. For around 30% of the samples, the spectral signatures are influenced by the two experimental setups. Outcomes suggest that for the majority of the samples green, blue, red-edge and some infrared bands are suitable for the beach litter detection.

Marine Oil Pollution Monitoring Based on a Morphological Attention U-Net Using SAR Images.

This study proposed an improved full-scale aggregated MobileUNet (FA-MobileUNet) model to achieve more complete detection results of oil spill areas using synthetic aperture radar (SAR) images. The convolutional block attention module (CBAM) in the FA-MobileUNet was modified based on morphological concepts. By introducing the morphological attention module (MAM), the improved FA-MobileUNet model can reduce the fragments and holes in the detection results, providing complete oil spill areas which were more suitable for describing the location and scope of oil pollution incidents. In addition, to overcome the inherent category imbalance of the dataset, label smoothing was applied in model training to reduce the model's overconfidence in majority class samples while improving the model's generalization ability. The detection performance of the improved FA-MobileUNet model reached an mIoU (mean intersection over union) of 84.55%, which was 17.15% higher than that of the original U-Net model. The effectiveness of the proposed model was then verified using the oil pollution incidents that significantly impacted Taiwan's marine environment. Experimental results showed that the extent of the detected oil spill was consistent with the oil pollution area recorded in the incident reports.

Oyster shell based indirect carbonation integrated with probiotic encapsulation.

Recycling oyster shells-an abundant industrial waste-is essential to reduce marine pollution. Indirect carbonation is promising; however, is cost-prohibitive. This study is a pioneering endeavor to merge indirect carbonation and probiotic encapsulation technologies using oyster shells. Probiotics were encapsulated in the CaCO3 produced through indirect carbonation with oyster shells, and the performance was evaluated. Confocal laser scanning microscopy certified the survival of a substantial proportion of the encased probiotics. Importantly, the majority of the enveloped probiotics demonstrated robust survivability while passing through gastrointestinal and bile fluids. These findings underscore the applicability of oyster shells as an optimal precursor for probiotic encapsulation which is eco-friendly and addresses the challenges faced in industrial waste recycling. This novel approach overcomes the economic limitations associated with indirect carbonation and mitigates the shortcomings of existing probiotic encapsulation methods. Convergence of indirect carbonation and probiotic encapsulation technologies can chart new routes for the environmental sector.

Optical Remote Sensing Methods for Floating Marine Debris Detection – Review and Bibliography Analysis

In the last several decades, the disposal and accumulation of debris in the marine and coastal environment has been one of the biggest and fastest-growing threats to the health of the world's oceans. Marine debris is present in all marine habitats and represents a great danger to global environmental and human health. Therefore, this paper aims to support efforts to achieve Good Environmental Status with respect to marine debris in all oceans and seas. The application of optical remote sensing methods for floating marine debris detection was briefly reviewed and the bibliometric analysis of the professional and scientific literature elaborated upon. In the overview part, previously used marine debris detection methods have been listed. The WoSCC (Web of Science Core Collection) and Scopus databases were considered, and the R Studio Bibliometrix and Biblioshiny software tools used for bibliometric analysis. 209 documents that can be classified into 43 research fields were identified in the two databases. Approximately 20% of the documents were published in two journals: the Marine Pollution Bulletin and Remote Sensing. Marine debris research was mainly published in the USA, Portugal, Italy, the United Kingdom, Germany, and China. A total of 54 countries participated in the publication of documents and it should be emphasized that all countries have shown great interest in international cooperation during the scientific research on marine debris. Scientific research on marine debris was found to have increased significantly since 2017, which is highly important for the protection of the environment and human health.

Enhanced detection and classification of microplastics in marine environments using deep learning

Microplastics (MPs) pose a growing environmental threat due to their accumulation and ecological impact. This study aimed to overcome the limitations of traditional methods, which are labor-intensive and prone to errors, in order to detect and classify MPs more effectively against marine pollution. We assessed object detection and classification algorithms: YOLOv8x, YOLOv8x (with augmentation), YOLOv8m, YOLOv8m (with augmentation), YOLO-NAS-L, and YOLO-NAS-L (with augmentation), focusing on four MP morphologies: fiber, film, fragment, and pellet. The dataset was divided into 80 % for training (320 images), 20 % for validation (80 images), and a fixed testing set of 200 images. The images were augmented using rotation (+25° and −25°), resizing (640 × 640 pixels), zooming, auto-orient strips, flipping, and noise application. This expanded the training set by 300 %, resulting in a total of 1400 images. The YOLOv8 models, particularly when augmented, outperformed the YOLO-NAS-L models in both mAP@0.5 and precision across all categories. Notably, YOLOv8x achieved an exceptional 99.0 % in both precision and mAP@0.5, with an impressive inference time of only 1.2 ms per image. The implementation of augmentation significantly enhanced detection accuracy across various models. With augmentation, YOLOv8x, YOLOv8m, and YOLO-NAS-L consistently achieved precision levels exceeding 99 %. For real-time applications, YOLOv8x was selected for the web application designed to detect and classify MPs, providing a more accurate and efficient solution compared to conventional methods. This model serves as a valuable resource for researchers in MP analysis, improving accuracy and reliability in environmental monitoring.

Microplastic pollution in coastal surface seawater of Southern Vietnam.

Microplastics have recently emerged as a significant environmental concern due to their direct impacts on marine ecosystems. Vietnam, with its 3260-km coastline, faces an elevated risk of microplastic pollution due to various coastal anthropogenic activities. This study explored microplastic distribution in coastal surface seawater in the Southern Vietnam regions of Tien Giang, Can Gio, and Vung Tau. A total of 45 samples were collected in April, 2019, and the results showed that microplastics present at all sampling sites, with the abundance varying from 0.074 ± 0.109 pieces/m3 in Can Gio to 0.56 ± 0.35 pieces/m3 in Tien Giang. Estuarial sites showed higher abundances for all regions. Most microplastics were under 2.8mm, fragmented, and primarily white or transparent. Polypropylene, polyethylene, and ethylene-vinyl acetate were the dominant polymers. This research indicates the urgency of further investigations to comprehensively understand the influence of wind patterns and other environmental factors on microplastic distribution.

A Comparative Study of Media Symbols from the Perspective of Visual Grammar: A Case Study of Marine Ecological Protection Posters in China and Western Countries

Social developments are bringing about changes in how we communicate and represent ideas. With the tendency of globalisation, marine ecosystems are facing threats such as overfishing, pollution, and climate change, and marine ecological protection has become a focus of attention for all countries. This paper adopts Kress and van Leeuwen’s framework of visual grammar analysis to compare and analyse the use of symbols in Chinese and Western marine ecological protection posters from the perspectives of representational meaning, interactive meaning, and compositional meaning. Qualitative and quantitative analyses of 100 Chinese posters and 100 Western posters reveal similarities and differences in symbol selection, cultural context, and compositional approach. Results show that Chinese posters tend to integrate traditional cultural elements and natural symbols to convey the concept of environmental protection in a harmonious and warm way, such as the use of ink painting style and paper-cutting art to represent marine organisms, while Western posters focus on directly displaying the hazards of marine pollution by means of strong visual contrasts and modern design elements to stimulate the audience’s sense of urgency and responsibility, such as the display of marine animals trapped by plastic rubbish. This research not only deepens the understanding of the theory of visual grammar but also provides valuable references for the design of future environmental posters, emphasising the importance of using visual symbols and communication strategies in different cultural contexts in order to convey environmental messages more effectively and to promote the development of global marine conservation.

Water-soluble polysaccharides extracted from Enteromorpha prolifera/PVA composite film functionalized as ε-polylysine with improved mechanical and antibacterial properties

The issue of environmental protection has received sustained and widespread attention. In order to reduce environmental pollution related to traditional plastics, it is an incessant demand to design novel environment-friendly food packaging materials with excellent performance. Sulfated polysaccharide extracted from the “green tide” marine pollution Enteromorpha prolifera (SPE) has been innovatively transformed into a film-forming material for better utilization. The insufficient mechanical properties and limited functionalities, however, hinder its wide application. In this study, polyvinyl alcohol (PVA) was blended to enhance its mechanical properties and ε-polylysine (ε-PL) was incorporated to endow it with antimicrobial performance. A novel and biodegradable film composed of SPE, PVA, and ε-PL was fabricated by casting method. We further determined the physicochemical properties of composited films. Mechanical performance test revealed the tensile strength of SPE-PVA-PL films increased from 5.56 MPa to 6.65 MPa and the E% increased from 128.8 % to 246.9 % compared with that of SPE-PVA films. Antimicrobial tests showed the excellent antibacterial activity of SPE-PVA-PL films against representative microbial species, Staphylococcus aureus and Escherichia coli. The results of this study suggested that the SPE-based composite film has the potential to be used as a potential food packaging and wound dressing materials.

Implementation of a semi-automatic approach for detection and extraction of oil slicks using Sentinel-1: Case study of the Moroccan exclusive economic zone

Due to its strategic geographic location, Morocco experiences heavy ship traffic, which inevitably has consequences. Ship accidents and illegal discharges, commonly referred to as oil spills, are frequent and pose significant harm to the marine ecosystem. Therefore, employing new technologies, such as satellite monitoring, is crucial and will greatly enhance the ability to monitor and assess these oil spills. The present work is based on Sentinel-1 SAR images and aims to take into evidence the extent of the hydrocarbon marine pollution in all of the Moroccan EEZ. More than 220 possible cases were detected and mapped during the last decade (2014–2024). A batch process was developed to automate the detection of oil spills by identifying areas with reduced Normalized Radar Cross Section (NRCS) values. This process incorporates corrections, masks, wind field estimation, and oil clustering. The method successfully detected approximately 80% of the cases between Kenitra and Casablanca. The closest detected spill is located 1 km from the coast, the largest spill covers an area of 90 km2, and the most extended spill measures about 145 km. This study can help raise awareness among governmental authorities about potential environmental damage and can be used to train artificial intelligence models, which could simulate oil slick propagation.

Recent developments in building sustainable marine fisheries in China: Reflections on the 2023 Revision of the Marine Environmental Protection Law

As the ocean provides an environmental carrier for fisheries development, sustainable marine fisheries and marine environmental protection are highly synergistic and consistent. Facing traditional and emerging crises such as marine pollution, overfishing and climate change, China revised the Marine Environmental Protection Law in 2023. This article aims to evaluate whether the newly revised Marine Environmental Protection Law effectively responds to crises of sustainable development in marine fisheries and how it contributes to sustainable marine fisheries. The study has found that the 2023 revision enriches and improves China’s legal regimes on marine fisheries from multiple aspects, covering marine environmental supervision, marine ecological protection and the prevention and control of land-based pollution, engineering construction projects pollution, waste dumping pollution, vessel pollution and legal responsibility. The newly revised Marine Environmental Protection Law not only refines the institutional norms and intensifies the legal responsibilities of violations but also improves the systemic nature of the legislation, thus providing stronger legal guarantees for sustainable marine fisheries. However, there are also legislative shortcomings such as unclear connotations of the newly established legal regimes and insufficient response to overfishing and climate change. Nevertheless, China’s newly revised Marine Environmental Protection Law applies the methodology of integrated ecosystem management and comprehensively utilized regulatory measures such as command-and-control tools, honor encouragement and economic incentives to enhance its regulatory effect, also providing implications and insights for addressing the challenges of sustainable marine fisheries on a global scale.

A new optimized procedure for circular WasteWater sustainability: Coastal cities supporting agricultural rural communities

This proposal introduces a novel methodology that addresses the increasing irrigation demands driven by climate change and urban growth. Traditionally water-scarce areas are now facing severe water deficits, while wastewater volumes from treatment plants, often discharged into the sea, contribute to pollution. The proposed hybrid system strategy innovatively reallocates 33 hm3 of water annually to agricultural communities, employing a zero-discharge approach to prevent marine pollution. Evaluated from energetic, environmental, and social perspectives, this methodology shows a remarkable cost-benefit ratio exceeding 12, showing its feasibility. It features technical indicators for optimizing water distribution and regulatory components, applied effectively to 28,424 ha of farmland. This strategy meets 24.1 % of the irrigation needs in these regions while safeguarding coastal areas from degradation. Crucially, it integrates 11.3 GWh of renewable energy annually, underscoring its sustainability and enhancing its replicability for other water-deficient regions.

Photoinitiated Degradation Kinetics of the Organic UV Filter Oxybenzone in Solutions and Aerosols: Impacts of Salt, Photosensitizers, and the Medium.

Organic UV filters like oxybenzone (BP3) in sunscreens are seawater pollutants suspected to transfer to the atmosphere via sea spray aerosol (SSA). This study examines the photoinitiated degradation of BP3 in artificial and real seawater compared to SSA mimics containing NaCl and 4-benzoylbenzoic acid (4-BBA). We investigated pure, binary, and ternary mixtures of BP3, NaCl, and 4-BBA using solar-simulated light to isolate the effects of salt and photosensitization on BP3 degradation. Results showed significantly faster degradation in the aerosol phase (J eff,env ≈ 10-3-10-2 s-1 or t 1/2 < 10 min) compared to bulk solutions (J eff,env ≈ 10-6 s-1 or t 1/2 > 1 day). The photosensitizer enhanced BP3 photodegradation in both phases more than when mixed with salt or all three components in solutions. BP3 photodegradation was most enhanced by salt in the aerosol phase. High-resolution molecular analysis via Orbitrap LC-MS/MS revealed more acutely toxic compounds (benzophenone, benzoic acid, and benzaldehyde) in irradiated aerosols than in solution, supported by electronic structure and toxicity modeling. These findings highlight that seawater may serve as a reservoir for BP3 and other organic UV filters and that upon transfer into SSA, BP3 rapidly transforms, increasing aerosol toxicity.

Complementarity and sensitivity of benthic state indicators to bottom-trawl fishing disturbance.

Many indicators have been developed to assess the state of benthic communities and identify seabed habitats most at risk from bottom trawling disturbance. However, the large variety of indicators and their development and application under specific geographic areas and management contexts has made it difficult to evaluate their wider utility. We compared the complementarity/uniqueness, sensitivity, and selectivity of 18 benthic indicators to pressure of bottom trawling. Seventeen common datasets with broad regional representation covering a range of pressure gradients from bottom trawling disturbance (n = 14), eutrophication (n = 1), marine pollution (n = 1), and oxygen depletion (n = 1) were used for the comparison. The outcomes of most indicators were correlated to a certain extent with response to bottom trawling disturbance, and two complementary groups of indicators were identified: diversity-based and biological trait-based indicators. Trait-based indicators that quantify the changes in relative abundance of sensitive taxa were most effective in identifying benthic community change in response to bottom trawling disturbance. None of the indicators responded to the trawling pressure gradient in all datasets, and some showed a response that were opposed to the theoretical expectation for some gradients. Indicators that showed clear responses to bottom trawling disturbance also showed clear responses in at least one other pressure gradient, suggesting those indicators are not pressure specific. These results emphasize the importance of selecting several indicators, at least one from each group (diversity and trait-based), to capture the broader signals of change in benthic communities due to bottom trawling activities. Our systematic approach offers the basis from which scientific advisors and/or managers can select suitable combinations of indicators to arrive at a sensitive and comprehensive benthic status assessment.

Co-pyrolysis of plastic waste and macroalgae Ulva lactuca, a sustainable valorization approach towards the production of bio-oil and biochar

To address the pressing demand for sustainable energy in light of environmental challenges, this study explored the synergetic effects of the co-pyrolysis of polyethylene terephthalate (PET) and Ulva lactuca macroalgae to yield bio-oil and biochar. The objective is to enhance the bio-oil quality for wider usability and to combat marine pollution. By employing co-pyrolysis, notable progress has been achieved in bio-oil yield and quality, particularly in hydrocarbon content, through the integration of PET. The highest bio-oil yield of 37.91 % was achieved under optimal conditions at 500 °C with a feedstock mixture consisting of 40 % U. lactuca and 60 % PET. Under these conditions, the bio-oil exhibited a significant increase in hydrocarbon content, reaching 57.16 %, which is essential for improving its energy potential. Biochar quality was also enhanced, with the biochar from a 70 % U. lactuca and 30 % PET blend showing a BET surface area of 20.18 m2/g, compared to the initial 1.38 m2/g of raw U. lactuca, indicating improved surface properties. This study presents a sustainable energy generation and environmental preservation approach, underscoring the potential of synergistically utilizing marine resources and plastic waste.

Distribution characteristics and ecological risk assessment of heavy metal pollution in seawater near the Yellow River Estuary of Laizhou Bay

To understand the characteristics and pollution status of heavy metals in the intersection areas of Laizhou Bay and the Yellow River Estuary in Shandong Province, the contents of various heavy metals in surface seawater samples collected from this area in August 2022 were detected. The spatial distributions of the heavy metals were analysed, which exhibits a general decreasing trend in the concentrations of Hg, As, Cr, and Pb from west to east, while Cd, Zn, and Cu show the opposite trend. The average single-factor index P values decrease in the following order Pb > Zn > Hg > Cu > As > Cd > Cr, among which Pb, Zn, Hg, and Cu caused pollution in this area. The potential ecological risk index values indicate that the main heavy metal pollutants in study area are Hg and Pb, with Hg having the highest value, accounting for 74.7%, and being the main potential ecological risk factor. Correlation analysis shows that the most significant environmental factor affecting heavy metal content is salinity. According to the interactive heatmap between cluster analysis and station classification, the heavy metals have originated from industrial, agricultural, and domestic sewage discharge, surface runoff, river inputs, seawater aquaculture, maritime transportation, and fuel exhaust emissions. This research hopes to provide some reference value for the protection of marine and estuarine ecosystems.

Noise pollution from Arctic expedition cruise vessels: understanding causes, consequences and governance options

Significant increase in shipping in the Arctic has caught international and national attention. The rising presence of touristic expedition cruise vessels might describe a special case for noise as a marine pollutant while they seek exclusive opportunities to experience the Arctic first-hand. This interdisciplinary study develops a conceptual framework to investigate context-specific vessel noise cause-effect dynamics and how this knowledge can assist policymakers and industry in increasing environmental safety. The study comprehensively reviews noise-emitting activities from Arctic cruise expeditions and potential adverse consequences for Arctic endemic marine mammals. It further discusses governance options for mitigating these consequences. Internationally, legal adaptations in the shipping conventions MARPOL and SOLAS should recognise noise as harmful energy. This could facilitate the uptake of noise-level-based certification schemes in the Polar Code. These legal actions can be strengthened by extended collective self-governance and through introducing economic incentives at the port level.

Impact of the amended Chinese Marine Environmental Protection Law on the law enforcement action of the Coast Guard — With a focus on the discharge of ballast water after Japan’s releasing of nuclear wastewater into the sea

After Japan released nuclear wastewater into the Pacific Ocean, China amended and promulgated the Marine Environmental Protection Law (MEPL) on October 24, 2023. The 2023 MEPL grants the Coast Guard extraterritorial jurisdiction over marine environmental protection. Meanwhile, it removes the content related to immunity for the disposal of radioactive substances and strictly prohibits the discharge of such substances into the sea. It is suggested that the 2023 MEPL will impact Coast Guard law enforcement actions, particularly in cases involving the punishment of marine pollution caused by nuclear wastewater. Additionally, China's Civil Procedure Law on jurisdiction over foreign-related infringement cases was also amended in 2023. Chinese courts have gained broader jurisdiction in foreign-related tort cases. As a result, Japanese parties will face the risk of civil damage compensation litigation due to the disposal of nuclear wastewater.

Declines in coastal macrozooplankton communities within a recent climate and ocean tipping point in the Tropical South Atlantic

This study investigated whether variations in climate and ocean drivers on global, regional, and local scales affected macrozooplankton communities in a coastal protected area in Tamandaré Bay (northeastern Brazil). For this purpose, bimonthly field campaigns were carried out from June 2013 to August 2019. A significant tipping point (point of change, p < 0.001), with an abrupt increase in SST, was detected in the TSA (Tropical South Atlantic) index. This indicates the existence of a climate regime shift in the Tropical South Atlantic during the 2015/16 El Niño (EN) event. Extreme rainfall events were observed in Tamandaré Bay after this EN event, in 2017, 2018, and in 2019 (and more recently, in 2022). This extreme rainfall led to low-salinity events, increased variability in salinity, and significantly lower abundances in the period after the strong EN event, for socioeconomically relevant penaeid shrimp postlarvae and several other zooplankton groups (e.g., copepods, appendicularians, anomuran hermit crab larvae, and chaetognaths). We found a significant relationship between SSTs in the TSA region and penaeid shrimp recruitment in the study area, located leewards of the TSA index area. The decline in shrimp postlarvae and other macrozooplankton may be due to a combination of factors, such as climate and ocean shifts (atmospheric easterly waves disturbances, winds, precipitation, salinity) and possibly increasing marine pollution (related to extreme rainfall events, that convey macro- and microplastics, and pollutants from the continent). Cnidarian medusae and fish eggs were among the few “winners” of this ecosystem regime shift. Changes in climate, ocean, macrozooplankton, and shrimp postlarvae abundance evidence a relevant climate, ocean and ecosystem regime shift in this region with a tipping point during 2015/16 “Godzilla” El Niño. Possible future consequences in the context of persistent warming in the TSA region and the currently ongoing record strength 2023/24 EN event are discussed.