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Marine aquaculture in semi-enclosed bays can significantly influence nutrient cycling in coastal ecosystems. However, the impact of marine aquaculture on the dynamics of dissimilatory nitrate reduction processes (DNRPs) and the fate of reactive nitrogen remain poorly understood. In this study, the rates of DNRPs and the abundances of related functional genes were investigated in aquaculture and non-aquaculture areas. The results showed that marine aquaculture significantly increased the denitrification (DNF) and dissimilatory nitrate reduction to ammonium (DNRA) rates and decreased the rate of anaerobic ammonium oxidation (ANA), as compared with non-aquaculture sites. DNF was the dominant pathway contributing to the total nitrate reduction, and its contribution to the total nitrate reduction significantly increased from 66.72% at non-aquaculture sites to 78.50% at aquaculture sites. Marine aquaculture can significantly affect the physicochemical characteristics of sediment and the abundances of related functional genes, leading to variations in the nitrate reduction rates. Although nitrate removal rates increased in the marine aquaculture area, ammonification rates and the nitrogen retention index in the aquaculture areas were 2.19 and 1.24 times, respectively, higher than those at non-aquaculture sites. Net reactive nitrogen retention exceeded nitrogen removal in the aquaculture area, and the retained reactive nitrogen could diffuse with the tidal current to the entire bay, thereby aggravating N pollution in the entire study area. These results show that marine aquaculture is the dominant source of nitrogen pollution in semi-enclosed bays. This study can provide insights into nitrogen pollution control in semi-enclosed bays with well-developed marine aquaculture.

Pediatric tumors in the apex of the thoracic cavity are often diagnosed late due to the absence of symptoms. These tumors can be quite large at presentation with involvement of the chest wall, sympathetic chain, spine, and aortic arch. The tumors can also extend into the thoracic inlet and encircle the brachial plexus. Depending on the diagnosis, treatment may involve chemotherapy with subsequent surgery or require primary resection. Optimal exposure to resect large apical tumors with thoracic inlet extension is a surgical challenge. To date, several surgical techniques have been described to resect these tumors - including both anterior and posterior thoracic approaches. Each of these techniques can be limited by inadequate exposure of the mass. We describe an alternative approach to surgical resection of these masses that employs an extended sternotomy with a lateral neck incision. This report details two successful resections of large left apical masses with thoracic inlet involvement in children using this technique (Level of evidence 4).

“Colligation”, a term first introduced in philosophy of science by William Whewell (1840), today sparks a renewed interest beyond Whewell scholarship. In this paper, we argue that adopting the notion of colligation in current debates in philosophy of science can contribute to our understanding of scientific models. Specifically, studying colligation allows us to have a better grasp of how integrating diverse model components (empirical data, theory, useful idealization, visual and other representational resources) in a creative way may produce novel generalizations about the phenomenon investigated. Our argument is built both on the theoretical appraisal of Whewell’s philosophy of science and the historical rehabilitation of his scientific work on tides. Adopting a philosophy of science in practice perspective, we show how colligation emerged from Whewell’s empirical work on tides. The production of idealized maps (“cotidal maps”) illustrates the unifying and creative power of the activity of colligating in scientific practice. We show the importance of colligation in modelling practices more generally by looking at its epistemic role in the construction of the San Francisco Bay Model.

Antibiotics have been detected in aquatic environment around the world. Understanding internal concentrations of antibiotics in organisms could further improve risk governance. In this study, we investigated the occurrence of seven sulfonamides, four tetracyclines, five fluoroquinolones, and five macrolides antibiotics in six fish, four crustaceans, and five mollusks species collected from Qinzhou Bay, an important part of the Beibu Gulf in the South China Sea in 2018. 19 of all the 21 target antibiotics were detectable in biota. The total concentrations of the antibiotics ranged from 15.2 to 182 ng/g dry weight in all marine organisms, with sulfonamides and macrolides being the most abundant antibiotics. Mollusks accumulated more antibiotics than fish and crustaceans, implying the species-specific bioaccumulation of antibiotics. The pH dependent partition coefficients of antibiotics exhibited significantly positive correlation with their concentrations in organisms. The ecological risk assessment suggested that marine species in Qinzhou Bay were threatened by azithromycin and norfloxacin. The annual mass loading of antibiotics from Qinzhou Bay to the coastal land area for human ingestion via marine fishery catches was 4.02 kg, with mollusks being the predominant migration contributor. The estimated daily intakes of erythromycin indicated that consumption of seafood from Qinzhou Bay posed considerable risks to children (2-5 years old). The results in this study provide important insights for antibiotics pollution assessment and risk management.

The depositional history of the Hudson Bay Lowlands (HBL) in Ontario, Canada has created a low relief, poorly drained landscape, favouring the formation of one of the largest peatland complexes in the world. High volume dewatering associated with resource extraction in this area, such as the De Beers Victor Diamond Mine, tests the ability of the underlying confining layer to limit water losses in the peatlands above. This research quantifies the deepening of water tables and increase in effective stress related to mine dewatering and the resulting changes to bog and fen peatland hydrophysical structure and function. Long-term implications of these impacts are discussed. One impacted and two unimpacted transects were instrumented for meteorological (precipitation and evapotranspiration) and hydrophysical (hydraulic head, hydraulic conductivity (K

Microplastic (particle size5 mm) is considered an emerging threat to the marine environment, yet data are limited for coastal ecosystems. To provide information related to microplastic in a coastal system, we used alkaline tissue digestion and Raman spectroscopy to quantify the prevalence and composition (e.g. fiber, fragment, foam, etc.) of anthropogenic microparticles in the digestive tracts of northern anchovies (Engraulis mordax, anchovy, n = 24), and common murres (Uria aalge, murre, n = 19) from the Monterey Bay, California USA. We also determined microplastic prevalence and composition in seawater (n = 12 17-h sampling periods representing ∼46,000 L sampled) from two Monterey Bay intake systems (Moss Landing, CA and Santa Cruz, CA USA). Microparticles recovered from murre digestive tracts were assessed for estrogenic activity using an in-vitro estrogen receptor activation assay. Suspected anthropogenic microparticles based on visual characteristics were recovered from all sample types with ∼2 particles per 1000 L from the seawater sampling periods, 58% prevalence in anchovies, and 100% prevalence in murres. Across samples of seawater, anchovies, and murres, the most abundant microparticle type found were fibers (78%), followed by fragments (13%), foam (6%), film (2%), and beads (1%). Raman spectroscopy identified 57% of microparticles (excluding dye-prominent and unknown) as plastic (synthetic, semi-synthetic, or blends). Almost one quarter (23%) of the murre digestive tracts contained microparticles that exhibited estrogenic activity. Our study describes the widespread occurrence, composition, and potential estrogenic activity of microplastic in the Monterey Bay and provides important information to aid in the understanding of microplastic contamination in coastal systems.

Plastic pollution is a growing concern even in India's remotest oceanic islands. To understand the extent of the problem in relatively undisturbed areas of the Andaman and Nicobar Islands, we nested a microplastic survey within a year-long meroplankton study in the protected bay of the Lohabarrack salt water crocodile sanctuary, that lies on the less populated west coast of South Andaman Island. Surveys recovered microplastics year-round, in 299 out of 300 samples. The average microplastic density in the protected bay was 0.45 ± 0.32 particles per m

Hudson Bay is a small arctic inland shelf sea which receives large amounts of freshwater from riverine discharges, with marine flow from the north and the Atlantic. A warming climate has resulted in an expanded open water season which will result in an increase in shipping of fuel oil and petroleum to communities and mines on the western shore, increasing the risk of hydrocarbon releases. To evaluate the status of hydrocarbons, surface sediments were collected at 34 locations in the transportation route and offshore and analysed for several types of hydrocarbons. Total hydrocarbons varied by over 25 times between sites, reaching a maximum of 1116 μg/g OC (organic carbon basis) in Hudson Strait due to low molecular weight n-alkanes from marine primary production. The gross mean for all sites was 344 μg/g OC (GSD = 173-682), roughly equivalent to other remote sites in the Canadian Arctic with no known local hydrocarbon source. n-alkanes accounted for90 % of residues. Diagnostic ratios (e.g., Carbon Preference Index (CPI), Odd-Even Predominance (OEP)) indicated mixed sources of n-alkanes, likely due to the input from vascular plants and ombrotrophic peat in northern and western watersheds, and primary production within the Bay. The elevated proportion of high molecular weight n-alkanes at deep water sites is consistent with lotic particulate organic matter deposited in the nearshore environment and redeposited offshore. Ʃ

Microplastics (MPs) were sampled in three seasons from 2016 to 2018 in the Bay of Marseille, northwestern Mediterranean Sea, adjacent to a highly urbanized area. Six sites were selected according to their different characteristics (river mouth, treatment plants, protected marine area). Surface floating MPs were characterized (number, weight, typology and polymer) as was zooplankton. In addition, mussels were submerged and used to investigate ingestion. Finally, a hydrodynamic model was used to improve understanding of dispersion mechanisms. The annual averages of floating MPs values ranged from 39,217 to 514,817 items/km2. The MPs collected were mainly fragments principally composed of polyethylene and polypropylene. The mean abundance ratio (MPs/zooplankton) was 0.09. On average 87% of mussel pools were contaminated and ingested 18.73 items/100 g of flesh. Two hydrodynamic patterns were identified: the first retaining the MPs in the harbor, and the second dispersing them outside.

Deep-sea ecosystems play a key role in the cycling and vertical transfer of matter and energy in oceans. Although the contamination of deep-sea demersal and benthic organisms by persistent organic pollutants has been proven, deep pelagic species have been far less studied. To fill these gaps, we studied the occurrence of a large variety of hydrophobic organic contaminants including polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), legacy and alternative brominated flame retardants (BFRs) and per- and polyfluoroalkyl substances (PFASs) in crustaceans and fish species collected in the Bay of Biscay, northeast Atlantic. The results highlighted the global predominance of PCBs in fish, followed by OCPs, PFASs and PBDEs, with highly variable concentrations among species. Most of the chlorinated or brominated contaminants showed increasing concentrations with increasing δ

The rapid increase in seaborn trade since the 1990s has resulted in an increase in vessel-derived noise pollution, yet there is little evidence linking these activities to a decline in many marine taxa, such as seabirds. Algoa Bay, South Africa, is a marine biodiversity hotspot, providing habitats for the largest populations of endangered African Penguins (Spheniscus demersus), as well as other endangered seabirds, cetaceans and seals. The bay is situated on a major shipping route and since 2016 has hosted the first offshore ship-to-ship (STS) bunkering operations in the country, i.e. the supplying of fuel from one ship to another outside of harbours. Using Automatic Identification System (AIS) data, we estimated noise emissions from vessels as a proxy for underwater ambient noise levels within the core penguin utilisation area. Frequency of vessels using the bay doubled during our study, with numbers of bulk carriers increasing ten-fold. Ambient underwater noise levels were generally high in the bay (ca 140 dB re 1 μPa since 2015) but significantly increased by 2 dB SPL after the initiation of STS bunkering in 2016, corresponding to double the underwater noise intensity. This increase coincided with a significant and dramatic decline by 85% in penguin numbers from St Croix Island since 2016. Algoa Bay is now one of the noisiest bays in the world. This is the first study to assess the potential impact of vessel-derived underwater noise levels on a seabird population. Penguins, like marine mammal species, are known to be sensitive to marine noise pollution and urgent management interventions are required to mitigate this recent disturbance, to preserve the remaining stronghold of the African penguin and the marine mammals' populations sharing the penguins' habitat.

Cesium-137 concentrations in sediment (137Cs) at Tokyo Bay were measured at 26 stations during 2017. Average 137Cs concentrations at the Arakawa river mouth (117 ± 46 Bq kg−1) were approximately six times higher than those of the other stations in the bay (20 ± 16 Bq kg−1). There were radiocesium-bearing microparticles in the bay sediment as well as in suspended matter of Fukushima coastal waters. Radioactivity of radiocesium-bearing microparticles was estimated to be 0.12 Bq. However, the contributions of radiocesium-bearing microparticles to each 137Cs concentration of the bulk sample were low; 3% was the maximum. The 137Cs inventory in sediment at the entire bay was 0.67 TBq, showing that a large amount of 137Cs was supplied to the bay from the river following the Fukushima Daiichi Nuclear Power Plant accident. Approximately 9.2% of the 137Cs which was fallout in the drainage basin has already flowed into the bay from the watershed, which is approximately 3.2 times higher than that of a previous estimate.

To constrain the resuspension influence to the biogeochemical behavior of trace metals (TMs) in settling materials, the concentrations and chemical speciations of macro-elements (Al, Fe, Mn) and selected particulate TMs (V, Cr, Co, Cu, Zn, Ga, Sr, Cd, Ba, Tl, Pb, U) in trap-collected particles (TCPs), surface sediments (SS) and core sediment samples (CS5) of the Jiaozhou Bay were compared. Two approaches, mass conservation method and vertical two end-members mixing model, both calculated a resuspension ratio of more than 90%. Greater TM concentrations and Al-normalization levels than SS/CS5 determined the TCPs an important TM-sink, predominantly owing to grain-size effects and TCP-specific characteristics, i.e., structural capacity of organic-Fe associations for TMs' scavenging, preferential remineralization of TM than biogenic elements in autochthonous microorganisms. Comparison revealed distinct, Fe mineral controls on TM sequestration patterns: higher metal sequestration associated with amorphous Fe oxyhydroxides, while less reactive crystalline Fe oxides hold less metal. Nevertheless, turbulent hydrodynamics muted the wide TM retention divergences between TCP and SS, which should have happened based on different Fe minerals distribution for TCP/SS. The net effect of TM release by the organic carrier phase and then adsorption principally onto Mn/Fe oxyhydroxide phase for raised overall TCP-TM concentrations was also identified.

Wastewater treatment plants (WWTPs) cause approximately 25 % of microplastics (MPs) in the marine environment. While research on MPs in WWTP effluent has demonstrated that an abundance of particles enter the marine environment, little effort has gone to assessing MP abundances in coastal sediments to determine their seasonal and spatial variability. Here, we assessed MP abundances in sediments at sites of WWTP outflow and at non-polluted sites over six consecutive seasons within the St. Andrew Bay system in Northwestern Florida. We showed that MP abundances were highest at one of the WWTP sites, where they increased with increasing distance away from the input source (3.16 ± 1.59 MP/kg to 34.03 ± 11.69 MP/kg sediment dry weight). We also found that mean MP abundances were highest in the winter (12.41 ± 3.56 MPs/kg sediment dry weight) and lowest in the spring (2.17 ± 0.63 MPs/kg sediment dry weight). Therefore, while WWTPs differentially retain MPs in their removal processes, MP pollution in the St. Andrew Bay system shows seasonal dynamics like other studies. Although average MP abundance in surface sediments (0-5 cm) was higher than in subsurface sediments (5-10 cm) at all sites, this difference was not as substantial as has been found in other studies. Based on mean MP abundance in surface sediments, we estimate that there are 30 billion MPs within the surface layer of sediment in the St. Andrew Bay system, and that the particles export to the Gulf of Mexico because of seasonal flushing between the winter and spring. The distributions of MPs in the system were also likely driven by extreme weather events that occurred in the bay system during 2018 and 2020, which acts as a cautionary tale for coastal urban ecosystems in the face of sea level rise and climate change.

Eutrophication is a global problem for coastal ecosystems, one that Bohai Bay, China, has been severely afflicted due to rapid economic and social development in the past decades. It was urgent to manage the total maximum allocated loads (TMALs) of the total nitrogen (TN) and total phosphorus (TP) on land-based, which was closely related to coastal eutrophication. In this study, from the perspective of economy-resources-environment (ERE) system, we presented the fuzzy credibility constrained linear programming based on pressure-state-response (PSR-FCCLP) model, which calculated the TMALs of TN and TP at three credibility levels (λ = 0.55, 0.75, and 0.95) in Bohai Bay. The results showed that when the credibility level increased from 0.55 to 0.95, the TMALs of TN and TP would decrease from 13,573.38 t/a to 12,820.00 t/a and from 2665.58 t/a to 2514.90 t/a, respectively. This study will provide support for environmental management in coastal regions.

Considering the phasing-out of polybrominated diphenyl ethers (PBDEs), environmental concerns of PBDE alternatives and dechlorane plus (DP) are rising. Accordingly, this study investigates occurrence and ecological risks of PBDEs, PBDE alternatives and DPs in sediments of two littoral regions, the Pearl River Estuary (PRE) and Daya Bay (DYB), in southern China. Total PBDEs concentrations in surface sediments of the PRE and DYB were in the range (mean) of 0.30-28.7 (8.71) and 0.29-43.4 (6.05) ng/g dw, respectively. DP levels in surface sediments of the PRE (0.004-0.27 ng/g dw) were significantly higher than those in the DYB (0.005-0.24 ng/g dw) (p 0.05). BDE 209 was the predominant component, followed by DBDPE, exhibiting regional variations in BFRs usage. Vertical profiles of BFRs and DP in the PRE and DYB sediment cores exhibited clear anthropogenic influences. Risk quotients suggest critical ecological risks of tetra-, penta- and deca-BDE congeners in all the surface sediments.

The establishment of water quality criteria (WQC) for copper (Cu) was used as the basis for an ecological risk assessment of marine Cu pollution in Liaodong Bay, China. Published ecotoxicity data for Cu were obtained and supplemented with the results of acute Cu toxicity tests. The marine WQC for Cu in Liaodong Bay was developed using a species sensitivity distribution method with a safety factor of 2.0 and the USEPA acute-to-chronic ratio method. The ecological risk of Cu in Liaodong Bay was assessed by comparing the seawater Cu concentrations with the developed WQC. The results of this study showed that the acute and chronic Cu concentrations in Liaodong Bay were 3.31 and 2.18 μg/L, respectively. Comparison of the WQC to Cu concentrations in the bay resulted in risk quotients slightly1.0 and typically ≤2.0. These data suggest that certain organisms in Liaodong Bay are at risk. These results can assist in the development of a pollution control management approach for the bay.

In the present study, the Hg levels in freshly collected polychaete species and their associated sediments were evaluated from Todos os Santos Bay, Northeastern Brazil. Additionally, it was also measured the Hg distribution along the annelids' body parts (anterior region, abdomen, and posterior region). Total Hg concentration was as follows: 13.6-144 μg kg

Marine debris is often detected everywhere in the oceans after it enters the marine ecosystems from various sources. Marine litter pollution is a major threat to the marine ecosystem in Bangladesh. A preliminary study was conducted to identify the sources of marine litter (plastics, foamed plastic, clothes, glass, ceramic, metals, paper, and cardboard) along the Bay of Bengal coast. From the observations, the range of abundance of the collected marine litter was 0.14-0.58 items/m

A detailed study of a sediment core from Daya Bay (South China) has revealed three stages of heavy metal deposition over the past century. Prior to the 1980s, heavy metal concentrations were low with limited influence by human activities. From the 1980s to 2000, metal pollution intensified, and anthropogenic activities, such as oil and petrochemical industries, and fuel combustion, had the greatest direct influence on Hg, Ni, Pb, and Zn concentrations, whereas atmospheric deposition and mariculture were also contributors to the continued increase in Cr, Cu, Pb, Zn, and Ni. Since the year 2000, heavy metal concentration has declined and stabilized. It is noteworthy that anthropogenic input of Cu and Pb is ongoing and may result in a moderate pollution risk. Both modified pollution index (MPI) and modified ecological risk (MRI) consistently indicate that the ecological risk in terms of heavy metals in Daya Bay has remained moderate over the past 70 years.

A nested double neuston net was prepared and used to collect samples from the surface of coastal waters around Japan to obtain information about the properties of both small microplastics (SMPs;350 μm) and large microplastics (LMPs;350 μm). The SMP concentrations ranged from 1000 to 5900 pieces m

Metal/loid pollution from shipwrecking activities has drawn significant concern due to their persistent threat to the marine ecosystem and human health. We investigated the spatiotemporal distribution, pollution characteristics, risks, sources, and potential impact of metal/loids in the sediments and seafood in the Bay of Bengal at nearby open beaching shipwrecking yards in Bangladesh. We collected 78 sediments and 208 seafood samples from the exposed and control sites from 2018 to 2020 during the dry and wet seasons. The concentrations of 16 elements, including cadmium, arsenic, lead, chromium, manganese, copper, zinc, iron, tin, antimony, nickel, cobalt, molybdenum, vanadium, selenium, and thallium were measured using validated inductively coupled plasma-mass spectrometry (ICP-MS) methods. Based on the pollution indices (enrichment factor, geoaccumulation index, pollution index, and pollution load index), lead, arsenic, cadmium, selenium, copper, zinc, and tin from the dry season showed higher contaminations compared to the wet and their concentrations were increased from 2018 to 2020 with seasonal fluctuations. Sediment cadmium and arsenic posed relatively higher and moderate ecological risks. Health risk analysis indicated that lead, cadmium, and inorganic arsenic (estimated) in seafood species pose a possible health threat to the general population. Further, there were possible ecological and health risks for the metal/loids in combination based on the ecological risk index in sediment and the hazard index in seafood, respectively. Source apportionment suggested that anthropogenic activities through uncontrolled shipwrecking operations over the last four decades were the largest polluting dominator, contributing 55-77% of the metal/loid concentrations. Therefore, the data may inform mitigation strategies for emission control at the shipwrecking yards to protect marine ecosystems and their local population.

Refereed/Peer-reviewed This study establishes baseline water quality characteristics for the Gold Coast Broadwater, southern Moreton Bay (Australia) utilising routinely monitored parameters between 2016 and 2021, across 18 sites. Combined site mean concentrations of NOx-N, NH3-N and total nitrogen were 11.4 ± 33.4 μg/L, 12.7 ± 27.2 μg/L, and 169 ± 109 μg/L, respectively, whilst PO4-P and total phosphorous were 7.30 ± 5.10 μg/L and 21.7 ± 14.1 μg/L. Additionally, total suspended solids and turbidity combined site means were 6.6 ± 6.0 mg/L and 3.4 ± 2.9 NTU, respectively. During high rainfall periods nutrient concentrations increased by up to >200-, >150-, 15-, 12- and >12-fold for NOx-N, NH3-N, TN, PO4-P and TP, respectively, compared to quiescent conditions. Furthermore, TSS and NTU values increased by up to 15- and 40-fold during periods of measured rainfall compared to quiescent conditions.

Microplastic (500 μm using Attenuated Total Reflection Fourier-transform Infrared (ATR-FTIR) spectroscopy. A total of 85 putative particles, mostly in the shape of fibers (65.9 %), were sorted. However, none of the particles were identified as MP applying state-of-the-art methodology. Sorted fibers were further evidenced to originate from contamination during sample processing and analyses. We find that MP concentrations in the local food web of the Weddell Sea and Dronning Maud Land coastal and marginal sea-ice regions; the feeding grounds to chick-rearing emperor penguin adults, are currently at such low levels that no detectable biomagnification is occurring via trophic transfer. Being in contrast to MP studies on other Antarctic and sub-Antarctic penguin species, our comparative discussion including these studies, highlights the importance for standardized procedures for sampling, sample processing and analyses to obtain comparable results. We further discuss other stomach contents and their potential role for MP detection, as well as providing a baseline for the long-term monitoring of MP in apex predator species from this region.

Synthesizing large, complex data sets to inform resource managers towards effective environmental stewardship is a universal challenge. In Chesapeake Bay, a well-studied and intensively monitored estuary in North America, the challenge of synthesizing data on water quality and land use as factors related to a key habitat, submerged aquatic vegetation, was tackled by a team of scientists and resource managers operating at multiple levels of governance (state, federal). The synthesis effort took place over a two-year period (2016-2018), and the results were communicated widely to a) scientists via peer review publications and conference presentations; b) resource managers via web materials and workshop presentations; and c) the public through newspaper articles, radio interviews, and podcasts. The synthesis effort was initiated by resource managers at the United States Environmental Protection Agencys' Chesapeake Bay Program and 16 scientist participants were recruited from a diversity of organizations. Multiple short, immersive workshops were conducted regularly to conceptualize the problem, followed by data analysis and interpretation that supported the preparation of the synthetic products that were communicated widely. Reflections on the process indicate that there are a variety of structural and functional requirements, as well as enabling conditions, that need to be considered to achieve successful outcomes from synthesis efforts.

In this paper, a three-dimensional mathematical model of the rotary diesel particulate filter (RDPF) for truck diesel engine is established according to the fluid mechanics and porous media theory. The effects of inlet velocity and structure parameters (diameter ratio, expansion angle and filter length) on the flow uniformity in the RDPF are investigated. Furthermore, the Fuzzy grey relational analysis (FGRA) is employed to make a weight analysis of the influences of structure parameters on the regeneration performance and pressure drop of the RDPF. The results show that the velocity uniformity in the RDPF can be improved by properly reducing the inlet velocity, diameter ratio or expansion angle θ

Bay of Bengal (BoB) has immense significance with respect to ecological diversity and natural resources. Studies on microbial profiling and their functional significance at sediment level of BoB remain poorly represented. Herein, we describe the microbial diversity and metabolic potentials of BOB deep-sea sediment samples by subjecting the metagenomes to Nanopore sequencing. Taxonomic diversity ascertained at various levels revealed that bacteria belonging to phylum Proteobacteria predominantly represented in sediment samples NIOT_S7 and NIOT_S9. A comparative study with 16S datasets from similar ecological sites revealed depth as a crucial factor in determining taxonomic diversity. KEGG annotation indicated that bacterial communities possess sequence reads corresponding to carbon dioxide fixation, sulfur, nitrogen metabolism, but at varying levels. Additionally, gene sequences related to bioremediation of dyes, plastics, hydrocarbon, antibiotic resistance, secondary metabolite synthesis and metal resistance from both the samples as studied indicate BoB to represent a highly diverse environmental niche for further exploration.

Potentially hazardous metals (PHMs) in the coastal environment have become a great concern due to their easy bioaccumulation, poor biodegradability and high toxicity. Surface sediment samples were collected in a subtropical bay in South China to analyse the spatial variations, contamination level and potential sources of PHMs. The results indicated that the order of average contents of PHMs in Qinzhou Bay sediment was Zn Pb Cr Cu AsHg Cd. The most important potential ecological risk factor was Hg pollution in the Qinzhou Bay sediments. The positive matrix factorization (PMF) model results indicated that Cu, Pb, Zn, Cd and Cr mainly originated from natural sources while Hg and As were related to coal fired industrial inputs and petroleum production activities. The results could provide a basis for marine management to formulate relevant pollution prevention and control measures.

In this study, the virulence genes, antibiotic resistance of culturable Vibrio and the environmental factors affecting Vibrio abundance were analyzed in four seasons in DongShan Bay with different intensity of aquaculture practice. A total of 253 bacteria isolates were obtained, of which 177 Vibrio strains belonged to 26 species. Annual Vibrio abundance in this region ranged from 20 to 11,600 CFU mL

Anthropogenic activities in coastal regions cause risks to the environmental and human health. Due to the carcinogenic and mutagenic potential, polycyclic aromatic hydrocarbons (PAH) are considered priority for monitoring. Most of the Brazilian production of Crassostrea gigas oysters are placed in the Bays of Santa Catarina Island. The aim of this study was to evaluate molecular responses (phase I and II of biotransformation and antioxidant defense) of C. gigas from six oyster farming areas potentially contaminated by sanitary sewage in Florianópolis Metropolitan (SC, Brazil): Santo Antônio de Lisboa, Sambaqui, Serraria, Caieira, Tapera, Imaruim. We evaluated the transcript levels of CYP1A1-like, CYP2-like, CYP2AU2-like, CYP356A1, GSTA1A-like, GSTO.4A-like, SULT-like, SOD-like and CAT-like by qRT-PCR. Only oysters from Caieira showed levels of thermotolerant coliforms allowed by the law. Chemicals analyses in soft tissues of oysters showed low to average levels of PAH in all monitored areas. Enhanced transcript levels of phase I (CYP1A1-like, CYP3564A1-like, CYP2-like and CYP2AU2-like) were observed in oysters from Serraria and Imaruí, suggesting higher biotransformation activity in these farming areas. Regarding phase II of biotransformation, GSTO.4A-like was up-regulated in oysters from Imaruí compared to Caieira and Santo Antônio de Lisboa. An upregulation of SOD-like and CAT-like were observed in oysters from Imaruí and Serraria, suggesting that oysters from these sites are facing higher prooxidant conditions compared to other areas. By integrating the biological and chemical data it is suggested that human-derived contaminants are affecting the oyster metabolism in some farming areas.

Microbial communities from Sepetiba Bay (SB, Rio de Janeiro, Brazil), characterized by 16S rRNA gene (V4-V5 region) sequencing analysis, were found to be correlated with the metallic contamination factor and the Quality Ratio (QR) index. Consistently, the predicted function of microbial communities, obtained with Tax4Fun2, showed that the functional patterns in SB internal sector under the highest anthropogenic pressure were different from that observed in the external sector with the lowest contamination level. Signal transduction, cellular community, membrane transport, and energy metabolism were among the KEGG pathways favored by metallic contamination in the SB internal sector, while lipid metabolism, transcription, and translation were among the pathways favored in the SB external sector. Noteworthy, the relative proportions of KEGG pathways and genes associated with metallic homeostasis showed significant differences according to the SB sectors, consistently with the ecological risk classification (QR index) of sediments. The functional prediction approach is an economically viable alternative and presents an overview of the main pathways/genes favored in the SB microbiota exposed to long-term pollution. In contrast, the microgAMBI, ecological status index based on bacterial community composition, was not consistent with the metallic contamination of SB, suggesting that this index requires improvements to be applied in tropical areas. Our study also revealed a strong correlation between metal resistance genes (MRG) and antibiotic resistance genes (ARG), indicating that MRG and ARG are co-selected by the metallic contamination prevailing in SB.

The nutrient status in Laizhou Bay has changed in composition and structure as a result of anthropogenic activities and climate change, which has led to several environmental problems (e.g., eutrophication, organic pollution and red tides). To better understand the spatiotemporal variations in dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), and eutrophication in the Laizhou Bay, we collected historical research data and conducted four cruises in 2021. The highest surface DIN was found to occur in autumn and predominantly concentrated in the southwestern bay. The highest surface DIP content was found in winter and distributed in the northwestern bay. Surface organic pollution showed estuaries as the most polluted areas. In the past 40-60 years, the DIN, DIP, and eutrophication have shown an inverted U-shaped trend, and the bay has changed from N limitation to P limitation. Economic development, phytoplankton absorption, and bottom mineral release are factors influencing the content and distribution of nutrient in the bay.

Microplastics (MPs) are considered one of the significant stratigraphic markers of the onset of the Anthropocene Epoch; however, the interconnections between historic plastic production, waste management as well as social-economic and timing of MP accumulation are not well understood. Here, stratigraphic data of MPs from a sediment core from Xiamen Bay, China, was used to reconstruct the history of plastic pollution. Generalized Additive Modeling indicates a complex temporal evolution of MP accumulation. The oldest MPs deposited in 1952 was 30,332 ± 31,457 items/kg•dw, coincide with the infancy of the plastic industry and onset of the Anthropocene. The Cultural Revolution (1966-1976) curtailed these initial increases. Subsequent rapid growth in MPs during the late 1970s was peaked at 189,241 ± 29,495 items/kg•dw in 1988 and was followed by a drastic decline in the late 1980s to a low value in 1996 (16,626 ± 26,371 items/kg•dw), coinciding with proliferation of MP sources, coupled with evolution of plastic production, consumption, and regulation. Increasing MPs over the past decades implies that previous mitigation measures have been compromised by the escalated influx of MPs from increasing plastics production, legacy MPs remaining in circulation and insufficient waste management for a growing population. The present methodology and results represent a conceptual advance in understanding how changes in policy and economics over time correlate to changes in MP records in Anthropocene strata, which may help make decisions on plastic pollution mitigation strategies worldwide.

Microplastic transfer between horseshoe crabs (Limulus polyphemus) and migratory shorebirds through consumption of crab eggs was examined in Jamaica Bay, New York. Fertilized and unfertilized crab eggs, shorebird fecal pellets, beach sand, and bay water were processed with a hydrogen peroxide solution to remove organic material, then stained with a Nile Red to identify microplastics using fluorescence microscopy. Microplastics were present in all samples and ranged from approximately26-1300 μm. Unfertilized and fertilized eggs contained significantly higher numbers of microplastic particles per gram than shorebird fecal pellets, beach sand, and bay water. The presence of microplastics in unfertilized egg samples indicates that microplastics undergo maternal transfer during oogenesis. We estimated that 1 g of horseshoe crab eggs could contain approximately 426 to 840 microplastic particles, suggesting that shorebirds feeding on this resource could be ingesting a substantial burden of microplastics during their migratory stopover, much of which appears to be retained by shorebirds, rather than being eliminated in their fecal pellets.

To understand zooplankton community changes in the context of climate change and anthropogenic disturbances, we analyzed mesozooplankton samples from four seasons in the subtropical Daya Bay, which is susceptible to perceived disturbances in the South China Sea. The zooplankton community was found to be divided into two clusters, namely the Outer-bay Cluster (OC) comprising Noctiluca scintillans, Temora turbinata, and Paracalanus spp., and the Inner-bay Cluster (IC) which was dominated by Pseudevadne tergestina, Oikopleura rufescens, and Paracalanus spp. The OC was recorded in waters with low Chl a concentrations and high salinity, coinciding with open seawater intrusion. The IC occurred in waters with high Chl a concentrations, low salinity, with terrestrial inputs from the Dan'ao River. The dominant cladoceran species has changed in spring from Penilia avirostris to Pseudevadne tergestina owing to suitable temperature conditions and the low wind speed in this region. Most of the keystone species recorded during all seasons were found to be copepods based on co-occurrence network analysis. Numbers of keystone jellyfish (cnidaria) species, such as Geryonia proboscidalis, Chelophyes contorta, and Aeginura grimaldi were significantly higher in summer than in other seasons due to a low-temperature seawater intrusion, which can result in the highest stability of community structures and affect coastal food webs and fishery resources. Our results highlight that zooplankton community succession may occur with long-term temperature changes in the subtropical Daya Bay under global climate change conditions.

Freshwater ecosystems play a key role in global greenhouse gas estimations and carbon budgets, and algal blooms are widespread owing to intensified anthropological activities. However, little is known about greenhouse gas dynamics in freshwater experiencing frequent algal blooms. Therefore, to explore the spatial and temporal variations in methane (CH

The largest semi-enclosed sea of China, the Bohai Sea, serves as an important sink of microplastics (MPs) originated from terrestrial and marine sources. This study summarized potential sources and migration pathways of MPs in the Bohai Sea and reviewed the abundance and characteristics of MPs in water, sediments, and organisms. Coastal anthropogenic activities (i.e., plastic production, agricultural activities, and industrial and domestic sewage discharge) and marine origins (i.e., aquaculture, marine litters, and transportation) might accelerate the MPs enrichment in the Bohai Sea. The abundance of MPs ranged from 0.07 to 5200 items/m

The decrease of river runoff caused by the intensified human activities (e.g. artificial dams) and increasing intrusion of high salinity water in the coastal bays have become a worldwide environmental problem. However, the mixing can hardly be identified by traditional method with temperature and salinity due to the complicated water sources in the coastal area. Thus, it is difficult to quantify the impact of intrusion of high salinity water on coastal ecological environment. Here, seasonal dual water isotopes (δD and δ

Microplastic contamination is an emerging global threat for various marine organisms. Marine invertebrates such as bivalve mollusks are more susceptible to the widespread presence of microplastics due to their limited abilities to escape from pollution exposure and they can readily ingest environmental pollutants like microplastics through their filter-feeding behaviors. In this study, microplastic contamination in bivalves related to species, spatial, and temporal variability were conducted. Results showed that the frequency of microplastic occurrence varied from 86.7 % to 93.3 % in six species of bivalves, and the average abundance of microplastics ranged from 3.5 to 8.6 items per individual or from 0.2 to 3.1 items per gram tissues wet weight. No significant difference was observed in microplastic abundances of bivalves collected from different research regions and sampling seasons. However, the sediment-dwelling bivalves had higher microplastics abundances than the water-dwelling bivalves. Microplastic features with various shapes, colors, sizes, and polymer types detected in bivalves were similar with those in seawater and sediment environments that they are living in. The potential risk assessment of microplastics in bivalves basing on polymer hazard index (PHI) was in the risk levels of II-III, implying that microplastic contamination in bivalves may pose health risk to human via seafood consumption.

The process and management of red tide in oligotrophic waters are poorly understood as most studies on red tide were focused on eutrophic areas. In this study, 404 red tide events together with the historical water quality dynamics during 1991-2020 were investigated in an anthropogenically influenced bay in China - Mirs Bay, whose most region is oligotrophic except small inshore areas. Red tides of oligotrophic offshore accounted for 20 % of all. With the effective governmental management on inshore areas, concentration of PO

Baseline marine litter abundance and distribution on Saint Martin Island, Bay of Bengal, were assessed. Seventy-two transects (100-150 m) along 12 km of coastline were surveyed for litter items every two weeks for two months. The most abundant items were polythene bags, food wrappers, plastic bottles/caps, straws, styrofoam, plastic cups, plastic fragments, fishing nets, clothes, and rubber buoys. Tourism, local markets, hotels, domestic waste, and fishing activities were primary sources of marine litter. According to the mean clean coast index (CCI), all transects were clean, of which 11.3 % and 14.1 % of sandy beaches and rocky shores with sandy beaches were reported dirty, respectively. Northern Saint Martin Island comprised sandy beaches (2.8 %) and was extremely dirty. In addition, plastic abundance index (PAI) analysis showed that 24 % of sites, out of 72 sites, were under "very high abundance", 33 % were "high abundance", 33 % showed "moderate abundance", and 4 % were classified as "low abundance". Establishing baseline results of marine litter abundance and distribution on Saint Martin Island may help improve island conservation and mitigation strategies (e.g., improved waste management, beach cleaning activities to raise public awareness, local government litter reduction policies, and increase local pro-environmental behavioral change).

Phosphorus usage is irreplaceable in agriculture; however, its excessive use leads to wastage of invaluable resources and significant soil surplus. Agronomic soil phosphorus surplus in Asian regions has a much higher level than the global average. And with rapid urbanization and population growth in the recent decades, Asian countries have seen a rise in environmental pollution levels also. This study assessed the detailed phosphorus budget in the Yamato River catchment, an urbanized coastal catchment in Asia, from 1940s to 2010s using Soil and Water Assessment Tool, comprehensively analyzed the effect of anthropogenic factors on long-term phosphorus loading and agronomic soil phosphorus balance. The results showed the peak period of total phosphorus loading and agronomic soil phosphorus surplus occurred in 1970s, at 895 tons/year and 36.6 kg/ha, respectively. The major reasons for increased phosphorus loading and soil surplus during 1940-1970 were rapid population growth and increased fertilizer usage, respectively. Since the 1980s, the construction of wastewater treatment system and reduction in agricultural land contributed to environmental improvement. These anthropogenic factors had a much stronger impact on phosphorus budget than climate change in the study catchment. Soil phosphorus balance is affected by a combination of factors, such as soil properties, fertilizer usage and applied schedule, precipitation event, and crop types. And soil phosphorus surplus may be severely overestimated if the non-point source loss due to precipitation factor is not fully considered.

In this paper, the spatial distribution, pollution degree, ecological toxicity and possible sources of seven potentially toxic elements (PTEs) collected from the surface sediments of Quanzhou Bay (QZB) were analyzed by obtaining concentration measurements. The results indicated that the areas with high Cu, Pb, Zn and Hg concentrations were mainly located in the Luoyang River estuary, while the areas with high contents of Cd and As appeared in the Luoyang River estuary area and in the southern part of QZB, respectively. The contamination indices showed that the Cd pollution degree was slight to serious, while other elements were slightly enriched. The calculation results of the potential ecological risk index (RI) and toxic risk index (TRI) indicated that Cd was the main element posing ecological risk among the PTEs of sediments in QZB, followed by Hg. Moreover, in approximately 30% of the surveyed sites, PTEs exhibited low toxicity to aquatic ecosystems. Finally, the self-organizing map (SOM) and positive matrix factorization (PMF) model were used to determine the PTEs sources. Natural sources, industrial emissions, and the combustion of fossil fuels were three main sources for PTEs in the surface sediments of QZB. This study provides a reference for assessing sediment pollution and managing marine pollution in QZB.

Polycyclic aromatic hydrocarbons (PAHs) are excellent tracers for fossil fuel combustion, natural fires and petroleum contamination, and have been widely used for reconstructing past wildfires and industrial activities at a variety of time scales. Here, for the first time, we obtain a high resolution (annual to decadal scale) record of PAHs from two parallel marine sediment cores from the Liaodong Bay, Northeastern China to reconstruct the industrial activities, spanning the past ∼ 200 years from 1815 to 2014. Our data indicate that PAH variations can be divided into four episodes: I) low (probably near background) PAHs from natural fires and domestic wood combustion during the pre-industrial period from 1815 to 1890; II) slightly increased (but with large fluctuations) PAH concentrations derived from intermittent warfare during the World War (1891-1945) and increased industrial activities after 1946 (1946-1965); III) a period of stagnation and, in some cases, reduction in PAHs during the "Cultural Revolution" (1966 to 1979); and IV) a rapid and persistent rise in PAHs post 1979 linked to fast economic development, with PAH concentrations doubled from 1979 to 2014. Changes in PAH distributions demonstrate major shifts in the dominant types of fuels over time from vegetation/wood, to coal and wood, followed by coal and petroleum (including vehicle emissions) over the past 200 years. We find that PAH records also show similar trend to domestic economy and the estimated regional Anthropocene CO

The light condensate fraction obtained from the low temperature Fischer-Tropsch (LT-FT) process is very complex and it is processed further by hydrotreating to produce hydrocarbon products that can be sold as final products. The mass% linear paraffins in some of the final paraffin products is listed as a required specification. Usually gas chromatography equipped with a flame ionisation detector (GC-FID) is used for the analysis of the condensate feeds to estimate the mass% linear paraffins that can be expected in the final products after commercial hydrogenation. This is an important parameter used in the blending of suitable condensate feeds. Due to the complexity of the condensate feeds, significant peak overlap occurs in the GC-FID analysis, making it difficult to accurately estimate the mass% linear paraffin content that will be obtained in the hydrogenated products. Inlet hydrogenation GC-FID analysis simplifies the prediction of the mass% linear content that can be expected in the paraffin product fractions from the analysis of a plant feed since the feed is hydrogenated in the GC inlet before GC-FID analysis. The results from this study showed that sufficient hydrogenation without significant peak tailing can be obtained in the GC inlet when using the appropriate mass and particle size Pd/Al

In marine environments, increasing occurrence and numbers of microbial Antibiotic Resistance Gene (ARG) subtypes, especially of new beta-lactamases, have received lots of attention in recent years. Updated databases with novel developed tools provide new opportunities to obtain more comprehensive ARG profiles as well as ARG-carrying hosts. Yet, ARGs in human-associated marine aquaculture environments, e.g. in China, remains largely unknown. Using metagenomic data, we revealed high numbers of Multi-drug Resistance, beta-lactamase and aminoglycoside genes throughout the year. Thereby, Alpha- and Gamma-proteobacteria were assigned to the majority of beta-lactamase-carrying hosts. From Metagenome-assembled genomes, three blaF-like beta-lactamases (91.7-94.7% identity with beta-lactamase from Mycobacterium fortuitum (blaF)) were exclusively observed in an unclassified Mycobacterium genus. Notably, other new beta-lactamases, VMB-1-like (n = 3) (58.5-67.4% identity to Vibrio metallo-beta-lactamase 1 (VMB-1)), were found in Gammaproteobacteria. Additionally, 175 Multi-drug Resistant Organisms possessed at least 3 ARG subtypes, and seven of the potentially pathogenic genera (n = 17) were assigned to Gammaproteobacteria. These results, together with high-risk ARGs (e.g. tetM, dfrA14 and dfrA17), provide hosts and new beta-lactamases of ARGs in Chinese coastal aquaculture.

Occurrence, spatiotemporal variation, sources, and ecological risks of 20 organophosphorus flame retardants (OPFRs) in water and sediments from Hangzhou Bay (HZB) and its adjacent East China Sea (ECS) were investigated in this study. The concentrations of OPFRs (∑OPFR) in water ranged from 0.51 ng/L to 885 ng/L, with chlorinated OPFRs having the highest value. For sediments, ∑OPFR ranged from 2.93 ng/g, dry weight (dw) to 37.8 ng/g, dw. The ∑OPFR in the water and sediments of HZB in summer was significantly (p 0.05) higher than that in autumn. Additionally, the pollution of OPFRs in HZB was higher than that in ECS, and the high-concentration areas appeared in the north and south banks of HZB and near the coast of ECS. Principal component analysis-multiple linear regression showed that the OPFRs in this region were mainly from industrial products (e.g., polyurethane foam/paint/coating/textiles/product processing). In terms of aquatic environments, ecological risks were in a low (∑RQs0.1) to moderate (0.1∑RQs1) level, with regard to median exposure levels, a moderate risk (0.1∑RQs1) was found in the sediments during autumn. This study can provide new insights into the OPFR pollution characteristic and ecological risk in a specific eco-environment.

We investigated the spatial distribution, mass profiles, and benthic risk assessment of a wide range of methylsiloxanes (MSs), including 7 cyclic MSs (CMSs; D3-D9; the number refers to the number of SiO bonds), 13 linear MSs (LMSs; L3-L15), and 15 modified and other MSs (MMSs) in sediments from the Tokyo Bay catchment basin, Japan. We observed widespread distribution of MSs (ΣCMS, ΣLMS, and ΣMMS) in the sediment samples, with concentrations of 1.0-6180 ng/g dry weight (dw), 1.8-10,100 ng/g dw, and0.31-210 ng/g dw, respectively. Our study is the first to measure various MMSs modified with hydrogen, vinyl, or phenyl groups; however, only methyltris(trimethylsiloxy)silane and phenyltris(trimethylsiloxy)silane were detected with high occurrence frequency. Notably, no elevated concentrations of MSs were observed downstream of silicone manufacturers, whereas the sediment was characterized by a specific D4/D5 ratio. With the Si-based mass profiles in extractable organosilicon (EOSi), the measured CMSs, LMSs, and MMSs accounted for 5.4%, 7.8%, and 0.2%, respectively. Unidentified EOSi (unknown fraction) constituted a major proportion of the EOSi in the sediment, with a mean of 87%, suggesting that the organosilicon environmental emissions were more than the measured MSs. In risk assessment of the adverse effects of D4, D5, and D6 in sediment on benthic organisms, the respective distributions indicated no overlap between the 95th percentile field sediment concentration and the 5th percentile chronic sediment no-effect concentration in organic carbon-normalized concentration. Although the hazard quotient compared with the predicted no-effect concentration for D5 and D6 exceeded the threshold level (hazard quotient ≥1), the results of probabilistic risk assessment for the three CMSs were not high enough to indicate a threat to benthic organisms in the study area.

Almost 140 years of industrial exploitation have severely degraded the environment of Bagnoli Coroglio (BC), the westernmost neighborhood of the city of Naples (Italy). In this peculiar area, however, geogenic processes overlap with the impact of human activities, making it difficult to distinguish between anthropogenic and geogenic pollution sources. This is particularly true for Arsenic, the concentration of which in the marine sediments largely exceeds the tolerable level for human health and the background value for local pyroclastics. After several studies have used traditional tools based on multivariate statistics, this article attempts at tackling the problem via numerical modeling, which provides a deeper insight into the physics that governs the pollution process. Therefore, we use a particle tracking model to assess whether arsenic levels in the seabed can be affected by the influx of thermal water from an artificial channel outfalling at the westernmost part of the coast The climatic forcings that drive the marine circulation are simplified to basic “scenarios”, in which wind and waves are stationary in strength and direction. Since the simulation time is much less than the contamination timescale, the comparison between numerical results and measurements is essentially qualitative and concerns the shape of contamination contours. It was found the primary forcing that enables seabed pollution is the tidal circulation, which, moreover, acts continuously in time. Quantitative arguments based on regression analysis suggest the discharge of thermal water explains almost a quarter of the observed pollution, which is consistent with previous research based on multivariate statistics.

An analytical framework was proposed for analyzing long-term chemical pollution in a coastal region with limited environmental data. The framework consists of compiling and synthesizing the available knowledge including the chemical's properties and the environmentally relevant data, as well as the data obtained by past monitoring studies. The gathered data is analyzed to assess multimedia fate of the pollutant by using fugacity-based intermedia transport calculations. Uncertainty analysis by applying Monte Carlo simulations is an integrated part of the framework. Dispersion factor (k) values were adopted, enabling a unified and intuitive way to define lognormal uncertainty distributions. The proposed framework was applied to polycyclic aromatic hydrocarbon (PAH) pollution in Izmit Bay, a coastal region in Turkey, impacted by industrialization and population growth. The analysis showed the importance of atmospheric pollution as a PAH source and indicated that Izmit Bay sediments may be at steady state for most PAHs.