In Penn Cove, ulvoid green algal mats occur annually. To examine seasonal variation in their causes, nitrogen and carbon were measured in Ulva lactuca in May, July, and September and stable nitrogen and oxygen isotope ratios were quantified in U. lactuca, Penn Cove seawater, upwelled water from Saratoga Passage, water near the Skagit River outflow, and effluents from wastewater treatment facilities. Ulvoid growth was nitrogen limited and the sources of nitrogen used by the algae changed during the growing season. Algal nitrogen concentrations were 0.85–4.55% and were highest in September and at sites where algae were abundant. Upwelled waters were the primary nitrogen source for the algae, but anthropogenic sources also contributed to algal growth towards the end of the growing season. This study suggests that small nitrogen inputs can result in crossing a “tipping point”, causing the release of nutrient limitation and localized increases in algal growth.

Invasive species can impact native species and alter assemblage structure, which affects associated ecosystem functioning. The pervasive Pacific oyster, Crassostrea gigas, has been shown to affect the diversity and composition of many host ecosystems. We tested for effects of the presence of the invasive C. gigas on native assemblages by comparing them directly to assemblages associated with the declining native European oyster, Ostrea edulis. The presence of both oyster species was manipulated in intertidal and subtidal habitats and reefs were constructed at horizontal and vertical orientation to the substratum. After 12months, species diversity and benthic assemblage structure between assemblages with C. gigas and O. edulis were similar, but differed between habitats and orientation, suggesting that both oyster species were functionally similar in terms of biodiversity facilitation. These findings support evidence, that non-native species could play an important role in maintaining biodiversity in systems with declining populations of native species.

This study tracked structure shifts of bacterial compositions before, during and after invading by crude oil to determine the microbial response and explore how temperature, dispersants and nutrients affect the composition of microbial communities or their activities of biodegradation in artificial marine environment. During petroleum hydrocarbons exposed, the composition and functional dynamics of marine microbial communities were altered, favoring bacteria that could utilize this rich carbon source such as the Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes phyla. Low temperature as a dominant factor decreased bacterial richness and catabolic diversity due to abated enzymes activities in correlation with the process of biodegradation. Dispersants exerted no negative consequences on microbial composition, however, bacterial composition by the Chloroflexi, TM6, OP8, Cyanobacteria and Gemmatimonadetes phyla increased. It seemed that more frequent fertilizer application could be equally safe to bacteria and increased significantly the abundance of bacterial strains but Actinobacteria phyla decreased.

Kuril Islands of the Sea of Okhotsk and the western part of the Bering Sea are an area of natural feeding of Pacific salmon, and the catch area of ones for food market. Food safety of products is an important task of aquaculture. Сoncentrations of HCHs (α-, β-, γ-) and DDT and its metabolites (DDD and DDE) were determined in organs of the pink (Oncorhynchus gorbuscha), chum (O. keta), chinook (O. tshawytscha), and sockeye (O. nerka), which caught from the natural aquaculture region of Russia (near the Kuril Islands (the northern-western part of the Pacific Ocean), the Sea of Okhotsk and the Bering Sea). The average total concentration of OCPs in organs of salmon from Western Pacific is lower than that in salmon from the North Pacific American coast and the Atlantic Ocean. The region can be used to grow smolts, which will be later released into the ocean.

Polypropylene, low-density polyethylene, and high-density polyethylene pre-production plastic pellets were weathered for three years in three experimental treatments: dry/sunlight, seawater/sunlight, and seawater/darkness. Changes in chemical bond structures (hydroxyl, carbonyl groups and carbon-oxygen) with weathering were measured via Fourier Transform Infrared (FTIR) spectroscopy. These indices from experimentally weathered particles were compared to microplastic particles collected from oceanic surface waters in the California Current, the North Pacific Subtropical Gyre, and the transition region between the two, in order to estimate the exposure time of the oceanic plastics. Although chemical bonds exhibited some nonlinear changes with environmental exposure, they can potentially approximate the weathering time of some plastics, especially high-density polyethylene. The majority of the North Pacific Subtropical Gyre polyethylene particles we measured have inferred exposure times>18months, with some >30months. Inferred particle weathering times are consistent with ocean circulation models suggesting a long residence time in the open ocean.

Mercury (Hg) contamination testing was conducted on winter-caught male spiny dogfish (Squalus acanthias) in southern New England and results compared to available data on Hg concentrations for this species. A limited risk-reward assessment for EPA (eicosapentanoic acid) and DHA (docosahexanoic acid) lipid concentrations of spiny dogfish was completed in comparison with other commonly consumed marine fish. Mean Hg concentrations were 0.19ppm (±0.30) wet weight. In comparison, mean Hg concentrations in S. acanthias varied geographically ranging from 0.05ppm (Celtic Sea) to 2.07ppm (Crete, Mediterranean Sea). A risk-reward assessment for Hg and DHA+EPA placed S. acanthias in both “low-risk, high-reward” and “high-risk, high-reward” categories for consumption dependent on locations of the catch. Our results are limited and are not intended as consumption advisories but serve to illustrate the need for making more nuanced, geo-specific, consumption guidance for spiny dogfish that is inclusive of seafood traceability and nutritional benefits.

Parrotfishes (f. Labridae) are a unique and ubiquitous group of herbivorous reef fishes. We compared the distribution and ecosystem function (grazing and erosion) of parrotfishes across 75 reefs in Arabia. Our results revealed marked regional differences in the abundance, and taxonomic and functional composition of parrotfishes between the Red Sea, Arabian Sea, and Arabian Gulf. High densities and diversity of parrotfishes, and high rates of grazing (210%year−1) and erosion (1.57kgm−2year−1) characterised Red Sea reefs. Despite Arabian Sea and Red Sea reefs having broadly comparable abundances of parrotfishes, estimates of grazing (150%year−1) and erosion (0.43kgm−2year−1) were markedly lower in the Arabian Sea. Parrotfishes were extremely rare within the southern Arabian Gulf, and as such rates of grazing and erosion were negligible. This regional variation in abundance and functional composition of parrotfishes appears to be related to local environmental conditions.

In this work, a hydrocarbon-degrading bacterium Y-1 isolated from petroleum contaminated soil in the Dagang Oilfield was investigated for its potential effect in biodegradation of crude oil. According to the analysis of 16S rRNA sequences, strain Y-1 was identified as Bacillus licheniformis. The growth parameters such as pH, temperature, and salinity were optimised and 60.2% degradation of crude oil removal was observed in 5days. The strain Y-1 showed strong tolerance to high salinity, alkalinity, and temperature. Emplastic produced by strain Y-1 at high temperatures could be applied as biosurfactant. Gas chromatography analysis demonstrated that the strain Y-1 efficiently degraded different alkanes from crude oil, and the emplastic produced by strain Y-1 promoted the degradation rates of long-chain alkanes when the temperature increased to 55°C. Therefore, strain Y-1 would play an important role in the area of crude oil contaminant bioremediation even in some extreme conditions.

Penaeus monodon, the Asian black tiger shrimp is one of the most widely consumed marine crustaceans worldwide. In this study, we examine and compare the fecal microbiota of P. monodon from highly polluted waters around Jakarta Bay, with those of less polluted waters of Bali. Using next generation sequencing techniques, we identified potential bacterial pathogens and common viral diseases of shrimp. Proteobacteria (96.08%) was found to be the most predominant phylum, followed by Bacteriodetes (2.32%), Fusobacteria (0.96%), and Firmicutes (0.53%). On the order level, Vibrionales (66.20%) and Pseudoaltermonadales (24.81%) were detected as predominant taxa. qPCR profiling was used as a confirmatory step and further revealed Vibrio alginolyticus and Photobacterium damselae as two potential pathogenic species present in most of the samples. In addition, viral diseases for shrimp were discovered among the samples, WSSV in Jakarta free-living samples, YHV in Bali free-living samples and IHHNV in both.

Marine environmental disturbance can be assessed directly from physical and chemical parameters, or indirectly by the study of indicator species. In this study, an integrated approach to monitor the Gulf of Milazzo, labeled as a highly contaminated site, is presented. A total of 83 samples were collected from hard and soft bottoms in 2010. In sum, 2739 specimens belonging to 246 taxa, two first records for the Tyrrhenian Sea (Micronephthys stammeri and Nicomache lumbricalis) and three nonindigenous species (Brachidontes pharaonis, Crassostrea gigas and Notomastus aberans) were recorded. Biodiversity and biotic indices and their relationship with sediment parameters and the level of pollutants were assessed to describe faunal assemblage and evaluate environmental quality. Pearson tests evidenced significant negative correlation between polychlorinated biphenyls (PCBs) and specific richness (p<0.10). A comparison of the standard and recorded biotic values showed that M-AMBI seems to be the index more representative of ecological quality status (EcoQ) in the Gulf of Milazzo. No evident signs were highlighted on the complex.