Marine Systems Research Articles

Transient Power Stabilization in Marine Microgrids: Improved Droop Control and Feedforward Strategies for Heterogeneous Gas Turbines with Hybrid Energy Storage

To address the complexity of power allocation in parallel operation systems combining single-shaft and split-shaft gas turbine generators, this paper proposes a coordinated power allocation strategy based on enhanced voltage droop control for marine power systems integrated with hybrid energy storage comprising flywheel and battery subsystems. Furthermore, to mitigate significant power sharing deviations during transient/pulsed load conditions in shipboard application, a feedforward compensation strategy is developed. Simulation results demonstrate that the improved droop control maintains power sharing deviations below 3.5% across steady-state operations and gradual load variations, ensuring system stability and balanced power distribution. However, abrupt load changes induce over 20% deviations, compromising parallel operation reliability. The proposed feedforward compensation strategy effectively restricts deviations within 4% under specified transient and pulsed load scenarios, satisfying both parallel operation criteria and grid power quality requirements. Validation is performed on a parallel system comprising two distinct gas turbine configurations.

An unusual mortality event for bottlenose dolphins links to altered diets resulting from ecological changes

Bottlenose dolphins (Tursiops truncatus) often have served as sentinel species for ecological changes in estuarine and marine systems. In 2013, the population of bottlenose dolphins in the Indian River Lagoon exemplified this role because an unusual mortality event involving malnourishment followed ecological changes. Potential causes of mortalities were investigated using surveys of key habitats and abundances of potential prey, stable isotope ratios from dolphins and potential prey, estimations of energy densities for key types of prey, and surveys of environmental conditions. The ecology of the lagoon changed substantially after 2011, with shading by intense, extensive, and long-lasting blooms of phytoplankton resulting in a > 50% decrease in the mean cover of seagrass and a > 75% decrease in mean biomass of drifting macroalgae. These reductions in key structural habitats preceded changes in ratios of stable carbon and nitrogen isotopes in samples of muscle from stranded dolphins. Changes in isotopic ratios indicated 9–25% increases in consumption of Archosargus rhomboidalis (sea bream) and 14–20% decreases in consumption of Elops saurus (ladyfish). The changes in diet reflected availability of prey, with a fisheries independent monitoring program yielding parallel changes in catches of sea bream and ladyfish. The dietary shift may have contributed to the 2013 unusual mortality event because sea bream yielded a lower mean energy density than ladyfish. Additionally, below average temperatures in 2010 and 2011 may have stressed some dolphins, particularly those that were garnering less energy from their diet. In contrast, osmotic stress was unlikely, given increasing salinities in the system. Overall, the results provided an example of links from blooms of phytoplankton to changes in habitat, availability of prey, and diets of dolphins followed by an unusual number of mortalities. Loads of nutrients that fueled the blooms are being reduced, with safe loads scheduled to be reached in 2035 and recognition that additional, adaptive efforts may be necessary to obviate harmful algal blooms.

Study on the Evolution of Estuarine Sedimentary Geomorphology Based on Remote Sensing Image Technology

The dynamic geomorphology and sediment transport processes of estuaries play a crucial role in understanding the interactions between terrestrial and marine systems. This study investigates the spatial and temporal differences in sediment dynamics, including grain size characteristics, sediment transport trends, and sedimentary environments, in the Yellow River estuary. It also examines the estuarine responses to changes in incoming water and sediment under varying hydrodynamic conditions. Using high-resolution remote sensing data and advanced image analysis techniques, including the ESP tool in eCognition, we optimized image segmentation scales and quantified interannual and interdecadal geomorphic siltation changes. The LIBSVM toolbox was applied for classification, achieving efficient, and accurate results for landform feature detection. Furthermore, the study integrates sediment dynamics modeling, remote sensing technology, and geographic big data to explore estuarine water and sediment transport processes. The findings provide a scientific foundation for the sustainable management of estuarine systems and contribute to improving geomorphic evolution modeling and image classification methodologies.

Research Progress of Fuel Cell Technology in Marine Applications: A Review

With the increasing severity of global environmental issues and the pressure from the strict pollutant emission regulations proposed by the International Maritime Organization (IMO), the shipping industry is seeking new types of marine power systems that can replace traditional propulsion systems. Marine fuel cells, as an emerging energy technology, only emit water vapor or a small amount of carbon dioxide during operation, and have received widespread attention in recent years. However, research on their application in the shipping industry is relatively limited. Therefore, this paper collects relevant reports and literature on the use of fuel cells on ships over the past few decades, and conducts a thorough study of typical fuel cell-powered vessels. It summarizes and proposes current design schemes and optimization measures for marine fuel cell power systems, providing directions for further improving battery performance, reducing carbon emissions, and minimizing environmental pollution. Additionally, this paper compares and analyzes marine fuel cells with those used in automotive, aviation, and locomotive applications, offering insights and guidance for the development of marine fuel cells. Although hydrogen fuel cell technology has made significant progress in recent years, issues still exist regarding hydrogen production, storage, and related safety and standardization concerns. In terms of comprehensive performance and economics, it still cannot effectively compete with traditional internal combustion engines. However, with the continued rapid development of fuel cell technology, marine fuel cells are expected to become a key driver for promoting green shipping and achieving carbon neutrality goals.

Ecological assessment of marine systems: How to conclude? Method and application to Western Mediterranean.

The ecosystem approach is generally considered as the best way to manage human activities impacting the marine environment. Nevertheless, more than 20 years after the emergence of this new paradigm, whereas ecosystem-based management is theoretically implemented through an essentially systemic approach, in practice, it appears that the application of standards and criteria and the use of indicators lead to a predominance of analytical approaches and to reporting formats that are inappropriate for defining action programmes. This paper proposes a new methodological framework to produce, in a synthetic form, integrated ecosystem assessments that go beyond the juxtaposition of sectoral analyses. Its guiding principle is to use the general knowledge of the marine environment (understanding of system dynamics and interactions within the system through a systemic approach) to put into perspective the results obtained through criteria and methodological standards (understanding the state of ecological components and the pressures affecting them through analytical approaches). The new methodological framework includes the identification of appropriate typologies for activities and pressures, as well as for ecological components. An essential point is to group the ecological components within the following compartments: pelagic habitats and food webs; benthic habitats; areas at the land-sea interface; protected species; and commercial species. On each of these compartments, the application of a selection of descriptors is possible. The result is an optimization of analyses in comparison with the indiscriminate use of descriptors on each of the ecological components considered separately. A case study is presented on the French Western Mediterranean.

Novel marine-climate interventions hampered by low consensus and governance preparedness

Novel marine-climate interventions are now being rapidly implemented to address both the causes and consequences of warming oceans. However, the governance implications of proposed upscaling of such interventions are uncertain. We conduct a survey of 332 intervention practitioners, revealing five types and 17 sub-types of interventions proposed or deployed in 37 marine systems globally. Most (71%) report marine-climate interventions aimed at supporting species and ecosystem adaptation, with 29% aimed primarily at climate mitigation and societal adaptation. Perceptions of climate benefits vary widely, with low consensus across practitioners on the climate goals of specific interventions. Intervention decision-making also remains focused on technical feasibility to meet minimum permitting requirements, with limited appraisal and management of broader ecological, cultural and social risks and benefits of intervention. Practitioners also warn that many marine-climate interventions are currently being tested and deployed in an under-regulated pseudo-scientific bubble.

Long Short Term Memory-Based Marine Data Prediction with Pearson Correlation

Marine data prediction plays a vital role in supporting decision-making in the field of marine environment and resources. However, the complexity of marine data, which is nonlinear and dynamic, is a significant challenge in producing accurate predictions. This study aims to explore the role of Long Short-Term Memory (LSTM) models in computer systems to predict marine data, focusing on Pearson Correlation analysis. The methods applied include collecting historical marine data, implementing LSTM models for prediction, and evaluating performance using metrics such as Mean Absolute Error (MAE). In addition, Pearson Correlation analysis is used to understand the relationship between variables in marine data. The results show that the LSTM model is able to produce predictions with a low error rate with a composition of training data and testing data of 80:20, resulting in Sea Surface Temperature (SST) = 0.0053, Sea Surface Salinity (SSS) = 0.0026, sea Surface Height (SSH) = 0.0061 and CHL-a = 0.0002 and shows a significant relationship between variables through Multivariate correlation analysis. This research contributes to the development of marine data-based prediction systems and provides implications for the world of marine resource research and management.

Slow growth and high longevity characterize the common, large Arctic brittle star, Ophiopleura borealis

The longevity (lifespan) and growth rates of a given species provide the basis for estimating its contributions to secondary production and energy flow in an ecosystem, for guiding management decisions, and determining recovery times after disturbances. For brittle stars, a class of echinoderms that dominate the megabenthos in various marine systems due to their often large populations, including those on Arctic soft bottom shelves, growth and longevity information can be estimated through growth bands in their ossicles (arm bones). Here, we estimated the maximum life span, age distribution, and growth rate of the common, large Arctic endemic brittle star, Ophiopleura borealis, from the northern Barents Sea. We counted growth bands in trawl-caught specimens using scanning electron microscope images of the innermost arm ossicles of 80 specimens spanning the known size range. These counts were corrected for overgrowth of the earliest growth bands, and growth parameters were estimated using common growth models. The age bands appeared as alternating layers of dense and less dense lines in the stereom of the ossicle fossae. The maximum corrected age band count was 39, which we infer as reflecting the age in years. This estimate is higher than for most other studied brittle stars, including polar species. Most individuals in the sampled population spanned estimated ages from 25-32 years. The growth constant k estimates of 0.09 from the Single logistic growth model and 0.01 from the specialized van Bertalanffy model indicate slow growth. The combined slow growth rate and long lifespan in Arctic brittle stars suggest that the large stocks found in Arctic regions may take a substantial time period to establish and recover from potential disturbances.

Hybrid machine learning algorithms accurately predict marine ecological communities

Predicting ecological communities is highly challenging but necessary to establish effective conservation and monitoring programs. This study aims to predict the spatial distribution of nematode associations from 25 m to 2500 m water depth over an area of 350,000 km² and understand the major oceanographic processes influencing them. The study considered data from 245 nematode genera and 44 environmental parameters from 100 stations. Data was analyzed by means of a hybrid machine learning (ML) approach, which combines unsupervised and supervised methods. The unsupervised phase detected that the nematodes were geographically structured in six associations, each with representative genera. In the supervised stage, these associations were modeled as a function of the environmental features by five supervised algorithms (Support Vector Machine, Random Forest, k-Nearest Neighbors, Naive Bayes, and Stochastic Gradient Boosting), using 80% of the samples for training, leaving the remaining for testing. Among them, the random forest was the best model with an accuracy of 86.4% in the test portion. The Random Forest (RF) model recognized 8 environmental features as significant in predicting the associations. Depth, the concentration of dissolved oxygen in the water near the bottom, the quality and quantity of phytodetritus, the proportion of coarse sand and carbonate, the sediment skewness, pH, and redox potential were the most important features structuring them. The inference of each association across the whole study area was based on the modeling results of the 8 significant environmental features. This model still correctly classified 90% of test data. Such findings demonstrated that it is possible to infer the spatial distribution of the nematode associations using only a small set of environmental features. The recommendation is thus to permanently monitor these environmental variables and run the ML models. Implementing ML approaches in monitoring programs of benthic systems will increase our prediction capacity, reduce monitoring costs, and, ultimately, support the conservation of marine systems.

Ocean alkalinity destruction by anthropogenic seafloor disturbances generates a hidden CO2 emission.

The seafloor is responsible for 40% of the alkalinity input to the ocean, thus contributing to the ocean's capacity to sequester atmospheric CO2. Anthropogenic seafloor disturbances induced by mobile bottom-contact fishing and dredging influence this natural carbon sink, yet the human impact on the ocean's alkalinity cycle remains poorly quantified. Model simulations show that the combined impact of mobile bottom-contact fishing (e.g., trawling) and dredging reduces natural alkalinity generation by 60 to 220 gigaequivalent year-1, which is equivalent to a reduction of the natural marine carbon sink by 2 to 8 teragrams CO2 year-1. Alkalinity destruction by anthropogenic seafloor disturbance hence generates a hidden CO2 emission, of which the impact is comparable to the estimated reduction of organic carbon burial by mobile bottom-contact fishing. Our analysis emphasizes that carbon accounting in marine systems should consider the anthropogenic impact on both the organic and inorganic carbon cycles.

The evaluation of biogenic silica in brackish and freshwater strains reveals links between phylogeny and silica accumulation in picocyanobacteria.

Through biosilicification, organisms incorporate dissolved silica (dSi) and deposit it as biogenic silica (bSi), driving the silicon (Si) cycle in aquatic systems. While Si accumulation in marine picocyanobacteria has been recently observed, its mechanisms and ecological implications remain unclear. This study investigates biosilicification in marine and brackish picocyanobacteria of the Synechococcus clade and two model freshwater coccoid cyanobacteria. Brackish strains showed significantly higher Si quotas when supplemented with external dSi (100 µM) compared to controls (up to 60.0 ± 7.3 amol Si.cell-1 versus 9.2 to 16.3 ± 2.9 amol Si.cell-1). Conversely, freshwater strains displayed no significant differences in Si quotas between dSi-enriched treatments and controls, emphasizing that not all phytoplanktons without an obligate Si requirement accumulate this element. The Si-accumulating marine and brackish picocyanobacteria clustered within the Synechococcus clade, whereas their freshwater counterparts formed a distinct sister group, suggesting a link between phylogeny and silicification. Rapid culture growth caused increased pH and led to dSi precipitation, influencing apparent dSi uptake; this was mitigated by pH control through bubbling. This phenomenon has significant implications for natural systems affected by phytoplankton blooms. In such environments, pH-induced silicon precipitation may reduce dSi availability impacting Si-dependent populations like diatoms. Our findings suggest brackish picocyanobacteria could significantly influence the Si cycle through at least two mechanisms: cellular Si accumulation and biologically induced changes in dSi concentrations.IMPORTANCEThis work provides the first evidence of biogenic silica accumulation in brackish picocyanobacteria and uncovers a link between phylogeny and biosilicification patterns. Our findings demonstrate that picocyanobacterial growth induces pH-dependent silica precipitation, which could lead to overestimations of cellular Si quotas by up to 85%. This process may drive substantial silica precipitation in highly productive freshwater and coastal marine systems, with potential effects on silica cycling and the population dynamics of Si-dependent phytoplankton. The extent of biosilicification in modern picocyanobacteria offers insights into the rock record, shedding light on the evolutionary and ecological dynamics that influence sedimentary processes and the preservation of biosilicification signatures in geological formations. Overall, this research adds to the significant impact that microorganisms lacking an obligate silica requirement may have on silica dynamics.

Life history implications of kinship structure in an Atlantic Herring aggregation

Kinship in natural marine fish systems has been little explored especially for very abundant and commercially exploited marine fish with broadcast spawning. Recent advances in genomics have however facilitated an improved understanding of population structure in marine systems at fine geographic scales. Here, we identify kinship structure in an aggregation of Atlantic Herring (Clupea harengus) juveniles. We identified 11 and potentially up to 14 half-sib pairs using a suite of 92 sequenced microsatellite DNA markers in a sample of N=1391 herring individuals comprising two cohorts (ages 0+ and 1+) collected from the 2018 Fall research survey of the Southern Gulf of St. Lawrence. We discuss the detection of three potential full-sibs in the data by way of association where two individuals are half-sibs to a third but not to each other. This putative full-sib pair was detected in the kinship analysis albeit outside the significance threshold used (λ* = 12). This study suggests the presence of kinship structure in a juvenile herring aggregation three months or more post hatching with implications for our understanding of herring early life history.

Occurrence of pharmaceuticals in muscle tissue of red drum (Sciaenops ocellatus) across subtropical estuaries: Comparison to blood plasma and implications for human exposure.

Occurrence of pharmaceuticals in muscle tissue of red drum (Sciaenops ocellatus) across subtropical estuaries: Comparison to blood plasma and implications for human exposure.

Numerical investigation of toroidal propeller: hydrodynamic and hydroacoustic study

ABSTRACT Given the widespread use of propellers in various marine vehicles, achieving high efficiency and performance under different operating conditions is crucial. This article investigates the hydrodynamic and hydroacoustic performance of a toroidal propeller and compares it with a B-Series propeller. Numerical simulations were conducted using computational fluid dynamics (CFD) based on the finite volume method (FVM) via the commercial STAR-CCM + software. A commonly used propeller, with available experimental and numerical data, was employed to validate the hydroacoustic and hydrodynamic simulations. The simulation results closely aligned with the experimental data. The comparison shows that the toroidal propeller achieves 13.3% higher efficiency under similar operating conditions compared to the B-Series propeller. Additionally, the toroidal propeller significantly reduces noise production. Pressure analysis reveals a reduction of approximately 50% in pressure fluctuations around the toroidal propeller. Moreover, the sound pressure level (SPL) around the toroidal propeller decreases by 2–14 dB (about 2–9%) at the first and second blade passing frequencies (BPF) compared to the B-Series propeller. The results of this study demonstrate the high potential of toroidal propellers for improving hydrodynamic performance and reducing noise in marine applications, which could contribute significantly to the design of advanced propellers and optimisation of marine systems.

A multifunctional organelle coordinates phagocytosis and chlorophagy in a marine eukaryote phytoplankton Scyphosphaera apsteinii.

Mixotrophy via phagocytosis can have profound consequences for the survival of marine phytoplankton and the efficiency of carbon transfer in marine systems. Little is known about the cellular mechanisms that underly nutrient acquisition via prey uptake and processing in mixotrophic phytoplankton. We used confocal microscopy, flow cytometry, and electron microscopy to assess phagocytosis and intracellular prey processing in the diploid calcifying coccolithophore Scyphosphaera apsteinii. Bioinformatic analysis was performed to develop a working model of the pathways that likely converge to regulate mixotrophic nutrition and autophagy. We found cells ingested proxy (up to 2 μm diameter) and natural (bacteria and cyanobacteria) prey particles that are processed within a single, prominent acidic vacuole detected in 80-100% of cells during exponential growth. This organelle was constitutive in cells through all growth phases to late stationary and is inherited when cells divide. Chloroplast fragments localized to this digestive organelle. A distinct, nonacidic vacuole containing polyphosphate was also identified in cells with ingested particles. We conclude a novel acidic organelle plays a multifunctional catabolic role in both mixotrophic nutrition (phagotrophy) and autophagy (chlorophagy). This discovery illustrates the dynamic nutritional strategies that marine phytoplankton, such as coccolithophores, have evolved to acquire and conserve nutrients.

Multi-omic stock of surface ocean microbiome built by monthly, weekly and daily sampling in Dapeng Bay, China

The coastal ocean is the dynamic interface where terrestrial, atmospheric, and marine systems converge, acting as a hotspot for microbial activity, which underpins the intricate web of carbon and nitrogen cycling. Dapeng Bay, a typical semi-enclosed bay along the southern coastline of China, is strongly influenced by monsoon climates and human activities. Despite its ecological importance, long-term observations and investigations into the microbial community structure in this region are notably lacking. To address this gap, we conducted a two-year continuous sampling from May 2021 to June 2023 to explore shifts in nearshore surface microbial communities and assess the long-term effects of environmental stressors. This study presents comprehensive amplicon, metagenomic, and metatranscriptomic information. We identified 3,600 amplicon sequence variants and recovered 1,216 high-quality metagenome-assembled MAGs, representing 17 bacterial and 3 archaeal phyla. Additionally, 587 MAGs were correlated with transcriptional activity, comprising 539 bacterial and 48 archaeal populations. This dataset is anticipated to provide a multi-dimensional perspective, enhancing our understanding of the complexity, dynamics, and adaptability of microbial communities in coastal environments.

Urbanisation Is Associated With Reduced Genetic Diversity in Marine Fish Populations.

The benefits to humans of living by the ocean have led many coastal settlements to grow into large, densely populated cities. Large coastal cities have had considerable environmental effects on marine ecosystems through resource extraction, waste disposal, coastal development, and trade and travel routes. While our understanding of the ecological and evolutionary consequences of urbanisation for wildlife in terrestrial systems has received considerable recent attention, the consequences of urbanisation in marine systems are not well known. Using microsatellite datasets associated with published research on marine fish population genetics, we built a global database of genotypic data spanning 75,361 individuals sampled from 73 species at 1085 sample sites throughout the world's oceans. We found that genetic diversity and effective population sizes were significantly lower at marine fish sample sites associated with denser human populations, regardless of species and locality. The loss of genetic diversity near denser human populations indicates habitats near human settlements are less able to support large populations. Small effective population sizes, in turn, dampen the efficiency of natural selection near dense urban settlements. The loss of genetic diversity near cities is concerning for maintaining functioning marine ecosystems and sustainable fisheries. Our work highlights the need to mitigate environmental threats from human activities and focus efforts on sustainable urban planning and resource use to conserve marine biodiversity and sustain coastal fisheries and ecosystems.

Evaluating the importance of mesopelagic prey to three top teleost predators in the northwest Atlantic Ocean

Abstract The ocean’s twilight zone is a vast area of the global ocean that lies between the sunlit surface waters and perpetually dark midnight zones, covering depths from ∼200 to 1000 m. Recent work in the twilight (or mesopelagic) zone has revealed unexpected biomass and diversity that may not only challenge scientific understanding of marine systems but also provide a new and largely untapped resource for fisheries harvest. A key knowledge gap in our understanding of the mesopelagic is how its food webs support foraging activity by commercially valuable, highly migratory top predators. Here, we use compound-specific stable isotope analyses to trace the flow of carbon through pelagic ecosystems in the northwest Atlantic to three predators: bigeye tuna (Thunnus obesus), swordfish (Xiphias gladius), and yellowfin tuna (Thunnus albacares). Temperate mesopelagic-associated carbon was estimated as both a direct and an indirect source of predator carbon, alongside temperate epipelagic and mixed epi-mesopelagic tropical carbon, via Bayesian mixing models. The contribution of temperate mesopelagic carbon to individual predators ranged from 5% to 94%, with means of 62%, 46%, and 28% for bigeye tuna, yellowfin tuna, and swordfish, respectively. We also found that carbon sources of predators shifted seasonally as they moved between temperate and tropical waters by contrasting tissues (liver, muscle) and season of sampling (summer, fall). These results inform our understanding of the adaptive value of deep diving behaviors in large marine predators and provide key estimates of food web linkages to inform multi-species fisheries management of both mesopelagic prey and migratory predators.

Detectability of Coastal Landforms on Titan With the Cassini RADAR

AbstractEarth's coastlines serve as the intersection for numerous physical and chemical processes between terrestrial and marine systems. Liquids of different compositions meet, materials eroded from the continents are concentrated in sedimentary deposits, and the diverse planform morphologies of coastal landforms are shaped by erosional and sediment transport processes. Accordingly, coastal landscapes preserve valuable records of processes that govern Earth's climate, materials, and tectonic history. Applying our understanding from Earth to the coastlines around Titan's liquid hydrocarbon seas allows us to investigate the climate history of the only other known active hydrological system. The study of Titan's coastlines, particularly its deltas, however, remains challenging due to the limitations of Cassini Synthetic Aperture Radar (SAR) data and the transparency of Titan's fluids to microwave radiation. To understand these limitations, we developed a numerical model to simulate Earth's coastlines as they would appear in Cassini SAR images. We show that multi‐kilometer‐scale landforms are detectable on Titan, provided there is sufficient contrast between the land surface and seafloor. We revisit Titan and show that many of its large coastal rivers do not terminate in deltas, in contrast to Earth. Additionally, we uncover submerged features on Titan's seafloors, suggesting sea‐level cycling and/or active sub‐aqueous flow. We propose preliminary hypotheses to explain the presence or absence of various coastal landforms on Titan, offering directions for future investigations into Titan's climate and materials. Moreover, we emphasize the opportunities and benefits a superior imaging system at Titan could provide to both Titan science and studies of Earth's changing coasts.

Enhanced uptake of perfluorooctanoic acid by polystyrene nanoparticles in Pacific oyster (Magallana gigas).

The effects of plastic pollution on marine organisms is of growing concern. The hydrophobic surface of plastics adsorbs organic contaminants and can alter the rate of chemical uptake in fishes. Per-fluorinated organic chemicals such as Perfluorooctanoic acid (PFOA) are highly hydrophobic toxic chemicals that adsorb to hydrophobic surfaces. We hypothesized that the presence of nano-sized plastic particles adsorbs PFOA and alter both the physical-chemical properties of the plastics and also enhance PFOA uptake into organisms. Using radiolabelled 14C-PFOA, we measured direct unidirectional uptake of PFOA in juvenile Pacific Oysters (Magallana gigas) at different (0.025, 0.50, and 0.100mg/L) concentrations, for different exposure periods (1, 2, 4, and 6h) and investigated whether varying concentrations (0.1, 0.5, 1mg/L) of either 500nm or 20nm polystyrene nanoparticles (PS-NPs) differentially altered the uptake rate of PFOA. Our results demonstrate that PFOA adsorbs to the surface of PS-NPs, altering PS-NP behaviour in solution and significantly increases the rate of uptake of PFOA in exposed Pacific oysters. PFOA uptake at 0.1mg/L was increased 2.3-fold in the presence of 1mg/L 500nm PS-NP and 3.2-fold in the presence of 1mg/L 20nm PS-NP. In a separate study to examine if PS NPs potentiate the biochemical response to PFOA, both 500 and 20nm PS-NP at 100mg/L increased the 1mg/L PFOA-induced oxidative stress by 2.5-fold and 3-fold respectively. These findings demonstrate that nanoplastics as co-contaminants in marine systems are able to adsorb PFOA and significantly potentiate its uptake and toxicity.