Species distribution models (SDMs) are used to detect potential effects of climate change on the habitat suitability of macrobenthos in the Yellow Sea and East China Sea. We obtained the presence/absence data of five dominant and characteristic macrobenthos from 268 sites investigated during 2000–2016 and 13 environmental variables from online datasets. The ensemble SDMs were constructed and were in good model performance for all five species. Model projections showed that the five species displayed different reactions to future climate scenarios: two species (the ophiuroid Ophiura sarsii vadicola and the bivalve Thyasira tokunagai) will likely contract their ranges, two (the crab Xenophthalmus pinnotheroides and the polychaete Sternaspis chinensis) will likely expand their ranges, and one (the ophiuroid Amphioplus japonicus) will likely move northward. Those differences were mainly due to their difference in thermal tolerance. Our findings provide important scientific basis for understanding the influence of climate change on marine benthic ecosystems.

Responses of different sexes of farmed Strongylocentrotus intermedius to chronic CO₂-induced seawater acidification were investigated in 120-day lab-based experiments. Four experimental groups were set up as one control group and three seawater acidification groups. The results showed that 1) Specific growth rate and the numbers of mature gamete cells declined in a pH-dependent way in both sexes of adult S. intermedius. 2) There were differences in SDMs identified in females and males reared in acidified seawater reflecting sex-specific response variation in adult S. intermedius. 3) The number of altered metabolic pathways exhibited a linear increasing trend as seawater pH declined in both sexes of adult S. intermedius. Meanwhile seawater acidification might affect metabolic processes via changing the relative expression and activity of key enzymes controlling the corresponding metabolic pathways of adult S. intermedius.

The combined effects of copper and polyvinyl chloride (PVC) microparticles were investigated on the metal accumulation, histopathological biomarkers, and targeted transcriptomics in Cyprinus carpio liver. The fish were exposed to 0.25 mg/L copper and/or 0.5 mg/L PVC microparticles over a 14-d period. The results showed that hepatic copper accumulation is facilitated by the PVC microparticles presence in water. All treatments induced significant hepatic stress and inflammation; however, the transcriptional responses involving in detoxification pathways and apoptotic mechanisms were mixed and often down-regulated in the fish exposed to copper and/or PVC microparticles. Exposure to copper and/or PVC microparticles induced hypermeia, leukocyte infiltration and increase in melanomacrophage centers number and area. Generally, the severity of the lesions was in the following order: PVC microparticles < copper < copper+ PVC microparticles. In conclusion, PVC MPs act as a copper vector, facilitating accumulation of copper in the fish liver and increasing the tissue damage.

Although nanoplastic (NP) pollution across aquatic environments has elicited widespread attention in recent years, its associated risks remain unclear. Using intertidal Monodonta labio as the test organism, RNA-Seq was performed to analyze the expression levels of genes under acute exposure to different concentrations of NPs in this study. A large quantity of differentially expressed genes (DEGs) were detected in response to three concentrations (0.1, 1, and 10 mg/L) of NPs. The expression levels of genes related to immunity, oxidative stress, and apoptosis were altered after NP exposure, and most of them were suppressed. These findings establish the foundation for future research on the biological effects of NP ingestion among aquatic organisms and their potential effects on humans via the consumption of these marine resources. However, further research on DEGs is needed to gain a better understanding of the molecular mechanisms behind their responses to NP toxicity in aquatic organisms.

Plastic pollution of our oceans from land-based sources and shipping spills raises concerns for marine ecosystems, maritime industries and human health. This paper examines the systems and processes in place in the case of plastic pollution due to a shipping spill in the North Sea and the instruments and mechanisms to hold polluters accountable. A desk-based analysis was conducted, and 11 expert interviews contextualised the desk findings. From the 263 reported incidents from 1917 to 2021, 39 % of the reported container loss cases occurred in, or near, the North Sea. Fragmented jurisdiction, frail and uncoordinated policies, aid the shipping sector to deflect responsibility. Around 62 % of the obstacles mentioned by the interviewees addressed governance, including, notably, the lack of international measures, and regulations on shipping routes to protect sensitive areas. The study also identifies the difficulty to enforce compensation for the damage made to ecosystems and biodiversity.

We studied the concentrations of terrestrial and anthropogenic radionuclides in seawater and shore sediment/sand of three selected regions; Khafji, Safaniyah and Menifah along the Saudi Arabian Gulf coast. The mean activity concentrations of the ²²⁸Ra, ²²⁶Ra, and ⁴⁰K in the analyzed sand samples are 5.9, 3.5 and 113.5 Bq/kg, and the respective values in seawater samples are 1.6, 0.8 and 10.4 Bq/L. All data show lower than the corresponding UNSCEAR (2000) reported world average values of 35, 30 and 400 Bq/kg for soil matrix. A few relevant radiological hazards were quantified by the estimation of the absorbed dose rate, and the results are compared with the prescribed limits set by international regulatory bodies. Measured data indicates that the studied coastal regions pose a negligible radiological hazards to the public, and show an insignificant radioactive loading to this coastal region by the Busher nuclear power plant.

The ecotoxicity of nitrofurazone was analyzed based on a community-based approach using periphytic protozoa. Median lethal concentrations (LC₅₀) within an exposure time of 30 min were determined by an acute toxicity test at 0, 1.5, 3, 6 and 12 mg ml⁻¹ nitrofurazone. Toxicity curve tests demonstrated a decreasing trend with increasing exposure time and was well fitted to the toxicity equation LC₅₀ = 32.85e⁻⁰.⁸¹⁴³ᵗ (t = exposure time; R² = 0.91; P < 0.05). Median inhibition concentrations (IC₅₀) for periphytic protozoan growth rates were obtained by chronic tests at 0, 1, 2, 4 and 8 mg ml⁻¹ nitrofurazone within 10 days exposure and were well fitted to the equation r% = 0.3686e⁻⁰.³⁵Cⁿⁱᵗ (Cₙᵢₜ is the concentration of nitrofurazone; R² = 0.92 and P < 0.05). These findings suggest that the LC₅₀ and IC₅₀ values of nitrofurazone can be predicted for any exposure time using periphytic protozoan communities as a bioassay model.

In this study, 214 surface sediment samples were collected from the offshore area of the Dongying coast and were analysed for heavy metals; particularly, their concentrations and pollution status were evaluated. The copper (Cu) and chromium (Cr) distributions were similar, their concentrations were the highest in the northeast areas and the Xiaoqing River estuary, where dominated by fine-grained sediments. Higher concentrations of lead (Pb), zinc (Zn), cadmium (Cd), and arsenic (As) were generally found in the offshore area of the study location, and the highest Cd concentration was observed in the Xiaoqing River estuary. The sediments were not polluted by Cu, Pb, Zn, and Cr; they were not polluted or moderately polluted by Cd and As. Results of the principal component analysis indicated that Cu, Pb, Zn, and Cr were derived from natural sources and Cd and As were derived from anthropogenic sources.

Coral communities in China's Great Bay Area (GBA) have experienced severe degradation, but only limited information is available about their community structure. We surveyed 20 sites across three regions (Daya Bay, Dapeng Bay, Wanshan Islands) in GBA to provide an updated baseline of these urban coral communities. Live coral cover varied substantially, with the lowest values (<2 %) found inside the highly urbanized Daya Bay, and highest values (40–47 %) from offshore islands that are less affected by human activities. The two sites with the lowest live coral cover had a high percentage of dead coral. Five groups of coral communities could be identified, with most of them characterized by dominance of massive and encrusting coral species. Both coral cover and generic richness were negatively correlated with dissolved inorganic nitrogen in the water column, indicating that nutrient pollution could potentially constrain the development of these urban coral communities.

Underwater radiated noise from shipping is globally pervasive and can cause deleterious effects on marine life, ranging from behavioural responses to physiological effects. Acoustic modelling makes it possible to map this noise over large areas and long timescales, and to test mitigation scenarios such as ship speed reduction or spatial restrictions. However, such maps must be validated against measurements to ensure confidence in their predictions. This study carried out a multi-site validation of the monthly and annual shipping noise maps for 2019 produced as part of the Joint Monitoring of Ambient Noise in the North Sea (JOMOPANS) programme. Spectral, spatial, and temporal differences between predictions and measurements were analysed, with differences linked to uncertainty in model input data and additional sources of anthropogenic noise in the measurements. Validating shipping noise models in this way ensures they can be applied with confidence in future management decisions to address shipping noise pollution.