Marine debris is defined as any manmade item, commonly plastics, which ends up in the ocean regardless of the source. Debris found along coastlines can cause harm or even death to nesting and hatchling sea turtles through ingestion, entrapment, or entanglement. Jekyll Island is a prominent nesting beach for loggerhead sea turtles with over 1700 emergences from 2012 to 2017. This study uses debris logged through NOAA's Marine Debris Tracker and loggerhead sea turtle nesting activity on Jekyll Island to generate density maps and evaluate possible interactions. These maps provide valuable information on portions of the coast most at risk for debris and sea turtle interactions. Using these maps help the GSTC Marine Debris Initiative focus citizen science efforts in high overlap areas of the beach. With marine debris being a global issue that impacts all sea turtle and beach nesting species, lessons learned can be applied across a wide range of taxa and management strategies.

Plastic pollution in oceans is a global problem, with growing research efforts focusing on the threat of microplastics (<5 mm fractions). A source of microplastics pollution is derived from personal care products that contain polyethylene micro-spheres which are not captured by wastewater plants. In this work, ten personal care products (mainly scrubs) containing microplastics and marketed in Spain, were physico-chemically characterized. The obtained results proved that those microplastics had different particle size and are presented in high percentages in some cases, between 6 and 7% of the total product. Products with smaller particles usually showed higher concentrations than products with larger particles. Although all the microplastics were shown to be polyethylene, some impurities were observed that demonstrated the presence of silicates and oxides in the microplastics. Regards to morphology, the shape of the particles was irregular in general, although some completely spherical particles can be observed.

In this study we report silica rich anthropogenic spherules from the marine environment. We found spherical, dumbbell, teardrop and fused spherules in Zuari estuary (near the Dona paula jetty), south west coast of India. The spherules were composed of SiO2 (69.8%), Na2O (13.2%), CaO (8.8%), MgO (3.8%), and traces of Al2O3, and FeO. Their high Na and Ca contents rules out the possibility of being an impact spherule or microtektite, or anthropogenic spherules coming from fly ash. Their elemental composition suggests that these are glass micro beads that have many applications including production of road and pavement marking materials, such as traffic paints. Considering that the glass micro beads are known to have high concentrations of Pb, As, and Sb that can leach into the marine environment, this study also raises questions regarding the impact of such spherules on marine biota, and highlights the need for further detailed study.

Microplastics and organic pollutants are typical contaminants in the marine environment. However, little is known about their interactions. In this study, the sorption of 3,6-Dibromocarbazole(3,6-BCZ) and 1,3,6,8-Tetrabromocarbazole (1,3,6,8-BCZ) by Polypropylene microplastic in simulated seawater was studied. Factors, including particle size, salinity and concentration, were investigated, and the experimental results were simulated using a mathematical model. Results showed that the pseudo-second-order kinetic model was more suitable to describe the sorption of polyhalogenated carbazole by microplastics, with equilibrium sorption times of 6 h and 8 h for 3,6-BCZ and 1,3,6,8-BCZ, respectively. Sorption capacity increased with decreasing particle size and the adsorption capacity increased initially and then decreased with increasing salinity, with a maximum sorption occurring at salinity of 14%. Moreover, the sorption amount increased with the increasing concentration of polyhalogenated carbazole. The sorption isotherms were confirmed as the extended Langmuir model and the extended Freundlich model, both of which were S-type.

Economically important marine organisms face severe environmental challenges, such as high temperature and low dissolved oxygen, from global climate change. Adverse environmental factors impact the survival and growth of economically important marine organisms, thereby negatively influencing the aquaculture industry. However, little is known about the responses of sea cucumbers to combined environmental co-stressors till now. In this study, ultra-performance liquid chromatography (UPLC) was utilized to obtain metabolic profiles of sea cucumbers. Changes in the concentrations of 84, 68, and 417 metabolites related to the responses of sea cucumbers to heat (26 °C), hypoxia (2 mg/L) and the combined stress, respectively, were observed and analyzed. Representative biomarkers were discussed in detail, including deltaline, fusarin C, halichondrin B and rapanone. The concentration of metabolites involved in the regulation of energy metabolism, including amino acid, carbohydrate and lipid metabolism were significantly changed, and the tricarboxylic acid (TCA)-cycle was significantly altered under heat plus hypoxia. We interpreted these changes partly as an adaptation mechanism in response to environmental stress. Based on the decreased accumulation of glutamine, we hypothesized that heat stress is the main factor that interferes with the process of glutamic acid-glutamine metabolism. The present study showed that combined environmental stressors have a more extensive impact on the metabolites of the respiratory tree in sea cucumbers than single stress. These results would facilitate further development of the sea cucumber as an echinoderm model to study mechanisms of response to adverse environments, as well as to help advance knowledge of the adaptation of marine organisms to global climate change.

Understanding the environmental context where heterogeneous ecological processes affect biotic interactions is a key aim of ecological research. However, mechanisms underlying spatial variation in trophic interactions linked to resource availability across ecosystem gradients remains unclear. We experimentally manipulated the interactive effects of predator fish and quantitative gradient of leaf detritus on macroinvertebrates and benthic algae. We found that non-linear changes in the strength of trophic cascades were strongly linked to the retention rates of experimental leaf detritus and also determined by predatory consumers. Retention rate of leaf detritus influenced the recruitment of predatory invertebrates and foraging preference of predators, accounting for largely the variations in shift of strengthening and weakening trophic cascades. Our results highlight the importance to identify joint processes of recruitment and foraging responses of functional consumer in understanding the impacts of both anthropogenic and natural alterations in subsidy on trophic interaction of coastal food webs.

In this study, twenty seven surface sediments were collected off Pushpavanam, Nagapattinam coast, southeast coast of India for understanding the sedimentological and geochemical behaviour after the Cyclone Gaja. The sediment samples were analysed for texture, organic matter (OM), carbonates, and trace metals such as Cr, Cu, Zn, Ni, Co including Fe and Mn. The Geoaccumulation index, contamination factor, enrichment factor and pollution load index revealed that Cu, Zn, Ni and Co is highly contaminated in the study area. Fe and Cr are moderately to considerably contaminated, while Mn shows uncontaminated.The principal component analysis also confirms the concentration of Cu, Zn, Ni and Co were mainly derived from the anthropogenic sources and related activities. Since Cyclones like Gaja often causes frequent ecological disturbance to the coastal environments and it distributes pollutants such as trace elements from localized area of contamination to offshore.

Today, four decades past peak anthropogenic lead emissions in the 1970s, dissolved lead (DPb) concentrations in the surface ocean remain elevated. To constrain contemporary sources and sinks of DPb, we studied high latitude surface waters of the North Atlantic and the Southern Ocean. We observed high concentrations of surface DPb (46 pmol kg⁻¹) near South Georgia in the Southern Ocean, sourced from glacial flour, while offshore DPb concentrations of 3–9 pmol kg⁻¹ were attributable to aeolian Pb inputs mainly from Patagonia. Dissolved Pb in the North Atlantic (4–29 pmol kg⁻¹) originated from aeolian particles from Northern Hemisphere sources. Extremely low DPb concentrations of <5 pmol kg⁻¹ found in both polar regions were the result of scavenging of DPb onto biogenic particles formed during spatially confined phytoplankton blooms, indicating that changes in phytoplankton abundance may alter the residence time and distribution of DPb in the surface ocean.

Estuaries provide significant cultural ecosystem services, including recreation and tourism. Disruptions of estuarine biogeochemical processes resulting from environmental degradation could interrupt the flow of these services, reducing benefits and diminishing the welfare of local communities. This study focused on recreational shellfishing in Buzzards Bay, Massachusetts (41.55°N, 70.80°W). Relationships among measures of recreational shellfishing, estuarine water quality, and local socioeconomic conditions were tested to understand how the benefits of cultural ecosystem services to local communities might be affected by declining water quality. Transferring estimated economic benefits from an analysis of nearby municipalities, the study finds that increases in Chl a during the 24-year period were associated with losses in recreational shellfishing benefits of $0.08–0.67 million per decade. The approach presented here suggests a more broadly applicable framework for assessing the impacts of changes in coastal ecosystem water quality on the welfare of local communities.

Marine aquaculture areas are facing stressed environmental challenges, especially the degradation of coastal ecosystems. Here a coordinated time-series study was used to investigate the coastal bacterioplankton biodiversity dynamics of the Yellow Sea, China. Bacterial 16S rRNA gene sequencing revealed a temporal pattern of decreasing of diversity in summer. Functional prediction indicated that metabolic pathways related to the adenosine triphosphate (ATP)-binding cassette transporters and other membrane transporters were significantly enriched in May, while the genetic information processing category was most abundant in March. The May microbiomes showed most significant positive correlation with phosphate concentration, while the August and November microbiomes correlated with temperature and chemical oxygen demand (COD) most, and the March microbiomes showed significant correlation with Cu2+ level, pH and salinity. The correlations between representative bacteria and environmental parameters revealed in this study may provide insights into the potential influences of human aquaculture activities, on the biodiversity of coastal bacterioplankton.