High-throughput sequencing of microbial assemblages has been proposed as an alternative methodology to the traditional ones used in marine monitoring and environmental assessment. Here, we evaluated pico- and nanoplankton diversity as ecological indicators in NW Mediterranean coastal waters by comparing their diversity in samples subjected to varying degrees of continental pressures. Using metabarcoding of the 16S and 18S rRNA genes, we explored whether alphadiversity indices, abundance of Operational Taxonomic Units and taxonomic groups (and their ratios) provide information on the ecological quality of coastal waters. Our results revealed that only eukaryotic diversity metrics and a limited number of prokaryotic and eukaryotic taxa displayed potential in assessing continental influences in our surveyed area, resulting thus in a restrained potential of microbial plankton diversity as an ecological indicator. Therefore, incorporating microbial plankton diversity in environmental assessment could not always result in a significant improvement of current marine monitoring strategies.

Several studies have shown the ubiquitousness of microplastics across ecosystems worldwide including significant amounts in beach sand. In Thailand, however, there is a lack of studies about the microplastic pollution of beaches. This study aimed to quantify microplastics at the high-tide line of 21 beaches along the eastern Gulf of Thailand. Observed amounts ranged from 420 to >200,000 counts/kg. Anthropogenic and environmental factors affect distribution and amount of microplastics. Tide-dominated beaches and beach sections protected by beachrocks exhibit higher microplastic amounts due to lesser hydrodynamics. While human activities have a visible impact, in some cases environmental factors seem to predominate. Despite effective protection efforts led by the government and NGOs, our study shows that the substantial microplastic pollution of beach sand requires a proper management system with appropriate laws and regulations, and a public awareness campaign to reduce effects of microplastics on organisms and their ecosystems.

Microplastics are proven as heavy metals vector, but the adsorption mechanism still unclear. This study investigated the adsorption of Pb and Cu in microplastics in the Musi River and the environment effect. This study was conducted in 10 stations along the Musi River to the estuary. The polymers of microplastics were dominated by PP and followed by PE, PES, PVC, and nylon. The average concentration of Pb (0.0347 mg L⁻¹ for water and 0.470 mg kg⁻¹ for microplastics) was higher than Cu (0.0138 mg L⁻¹ for water and 0.091 mg kg⁻¹ for microplastics). The highest concentration of both metals in water and microplastics were found in the estuary. Environment parameters have different effects on the adsorption. The present study found that the adsorption processes were following the Freundlich model. The interaction metal-microplastic was physisorption. Pb and Cu will attach through weak bonds and easy to release into the aquatic ecosystem.

Larvae released into the water column rely on chemical cues from the benthos for successful settlement. However, larval preference for substrates may be affected by rising seawater temperature brought about by global climate change. In this study, we examined the effect of elevated temperature on chemical cue preference by larvae of the scleractinian coral, Acropora tenuis, and the octocoral, Heliopora coerulea, collected from northwestern Philippines. At ambient temperature (28 °C), both H. coerulea and A. tenuis larvae showed preference for substrates containing either crustose coralline algae or crude ethanolic extracts from conspecific or congeneric corals. In contrast, at higher temperature (30 °C), greater preference was shown for substrates containing the crude extract from conspecific or congeneric corals. These results demonstrate that elevated temperature can change larval substrate preference, which will have downstream impacts on crucial biological processes, such as larval settlement and recruitment.

The fishery and mariculture industry contributes to social food supply and offers high-quality protein to humans. However, mariculture is recently regarded as an important source of marine microplastic pollution, which might even pose a threat to human health. Here we investigated a shrimp-culturing farm for 9 months in Longjiao Bay, a typical mariculture area in southeast China, to study the occurrence and seasonal variations of microplastics in the mariculture water. Results showed that microplastics were widely present (250–5150 particles/m³, mean 1594 particles/m³) in the water of culture ponds. Granules (41.36%) and fibers (34.93%) were the main components of microplastics and white (45.42%) is the dominant color, followed by yellow (32.13%) and black (19.55%). Most of microplastics had a particle size between 0.30 mm and 5.00 mm (92.03%). The proportions of PE (34.40%) and PET (30.18%) accounted for more than 60% of detected microplastics. The abundance of microplastics in mariculture water had a potential positive correlation with local seafood yield and a negative correlation with land areas. This study suggested that further research is needed to figure out the impact of the high levels of microplastic abundance in mariculture environments on organisms, especially cultured ones.

This baseline paper shows the Indo-Pacific mussel Perna viridis (Asian green mussel) inhabiting on floating plastic substrates in the Atlantico Department, as well as rafting on marine debris found at the Via Parque Isla de Salamanca (Magdalena). Both observations are the northernmost record of the species found in the Colombian Caribbean Sea. The above finding opens a new door that suggests that larval dispersion alone may not be the only process responsible for the presence of this invasive suspension-feeder bivalve because this species needs specific vectors for its dispersal. Some organisms such Perna viridis can persist in the marine environment, but they do not necessarily have a rafting capability that allows them to move over long distances. Floating structures as well as marine debris can serve as optimal substrates in the marine environment, contributing to an increase in the problems of non-native species on sites with a high degree of susceptibility to species invasion.

We investigated differences in the feeding habits of the starspotted smooth-hound, Mustelus manazo, in Tokyo Bay between the mid-1990s (low stock size) and the late 2000s (high stock size). The frequency of M. manazo with empty stomachs increased from 5.9% in the mid-1990s to 16.1% in the late 2000s. A decrease in the relative weight of the stomach contents was evident from the mid-1990s to the late 2000s, especially in the small size classes, along with changes in the species composition in the stomach contents. Although crustaceans were the main constituents of the stomach contents, the proportion of crabs increased while those of shrimps and hermit crabs decreased. Changes in the feeding habits of M. manazo may be associated with shifts in the benthic community structure in Tokyo Bay.

This paper explores people's knowledge and understandings of microplastics; the role of media in framing perceptions and socio-cultural dimensions to popular solutions to reduce single-use plastics. We conducted 6 focus groups (2016–17) involving participants with no obvious knowledge of microplastics and some with special interest. Most people were unaware of microplastics though environmentally conscious participants had heard of microbeads due to media reporting concerning regulation. Few made connections between their personal use of plastics and ocean pollution. Plastic pollution was associated with macro-plastic ‘islands’ in the Great Pacific Garbage Patch and powerful media images of charismatic wildlife entanglement remote from participants lives. The scale of microplastics (not easily detected), poor understanding of the science behind microplastics and cultural ideas about healthy and appropriate behaviour presents barriers to change. Science communicators, NGOs, industry and policy makers must take account of media representations and the culturally embedded nature of plastics in society.

The release of oil and gas at Mississippi Canyon Block 20 into the Gulf of Mexico has vexed response officials since 2004 when a regional seafloor failure toppled the Taylor Energy Company platform. Despite the completion of nine intervention wells, releases continue from the seafloor, mostly captured by a recently installed containment system. Toward informing resolution, this work applies chemical forensic and statistical analyses to surface sheens, sediments, and reservoir oil samples. Our results indicate sheens are chemically heterogeneous, contain remnant synthetic hydrocarbons likely discharged from well interventions prior to 2012, and require mixing of multiple chemically-distinct oil groups to explain observed variability in diagnostic ratios. Given the respite and opportunity afforded by containment we suggest leveraging ongoing collection activities to assess release dynamics, as well as engaging the National Academies of Science, Engineering, and Medicine, to evaluate potential solutions, associated risks, and to consider policy ramifications.

The 2010 Deepwater Horizon (DwH) oil spill in the Gulf of Mexico discharged ~3.19 million barrels of oil into Gulf waters, making it one of the largest marine disasters in history in terms of volume. We report on the results of a study to assess oil impacts to coastal fishes and invertebrates. Using two-decades of fisheries-independent data in coastal Alabama and Mississippi, we document variability following both natural and anthropogenic disturbances from two periods pre-DwH (1997–2001 and 2007–2009), one intra-spill period for acute DwH effects (2010–2012) and one period post-spill for chronic, longer-term impacts (2014–2017). Results indicated significant changes to community structure, relative abundance, and diversity in the intra-spill period. Causation for changes is confounded by variables such as behavioral emigration, altered freshwater inflow, death of consumers, and the mandated fishery closure. Results highlight the need for long-term, comprehensive monitoring/observing systems to provide adequate background for assessing future disturbances.