The dearth of long-time series hampers the measurement of the ecosystem change that followed the global marine climate shift of the 1980–90s. The sessile communities of Portofino Promontory reefs (Ligurian Sea, NW Mediterranean) have been discontinuously studied since the 1950s. Collating information from various sources, three periods of investigations have been distinguished: 1) 1950–70s; 2) 1980–90s; 3) 2000–10s. A cooler phase in time 1 was followed by a rapid warming in time 2, to stabilize at about 0.5°C higher in time 3. Human pressure grew impressively, especially after the establishment of a MPA in 1999. Multivariate analyses evidenced a major change of community composition in time 2. Some species disappeared or got rarer, many found refuge at depth, and among the newcomers there were recently introduced alien species. This study demonstrated the importance of descriptive historical data to understand magnitude and pattern of change in the long term evolution of marine ecosystems.

Contamination of sandy beaches of the Baltic Sea in Kaliningrad region is evaluated on the base of surveys carried out from June 2015 to January 2016. Quantity of macro/meso/microplastic objects in the upper 2cm of the sandy sediments of the wrack zone at 13 sampling sites all along the Russian coast is reported. Occurrence of paraffin and amber pieces at the same sites is pointed out. Special attention is paid to microplastics (range 0.5–5mm): its content ranges between 1.3 and 36.3 items per kg dry sediment. The prevailing found type is foamed plastic. No sound differences in contamination are discovered between beaches with high and low anthropogenic load. Mean level of contamination is of the same order of magnitude as has been reported by other authors for the Baltic Sea beaches.

Sharks are long-lived apex predators which can accumulate toxic metals such as mercury and arsenic. Samples of Sphyrna lewini and Carcharinus porosus were collected from two commercial fish landing sites in Trinidad. Heavy metal concentrations were determined in the muscle, dorsal fin, vertebrae and liver using atomic absorption spectrometric. The provisional tolerable weekly intake (PTWI) and target hazard quotient (THQ) were determined to assess the potential health risks to consumers. Mercury levels ranged between 74–1899μg/kg in S. lewini and 67–3268μg/kg in C. porosus. Arsenic levels ranged between 144–2309μg/kg in S. lewini and 762–6155μg/kg in C. porosus. Cadmium levels generally ranged between 0.27–27.29mg/kg in S. lewini and 0.6–29.89mg/kg in C. porosus. Lead levels generally ranged between 0.14 and 208.81mg/kg in S. lewini while C. porosus levels ranged between 0.30 and 459.94mg/kg. The PTWI and THQ values suggest that consumption of these shark species can therefore be a major source of exposure to lead, cadmium, arsenic and mercury in humans and is likely to have potential health risk over long term exposure.

Small-scale pollution events involve the release of potentially harmful substances into the marine environment. These events can affect all levels of the ecosystem, with damage to both fauna and flora. Numerous reporting structures are currently available to document spills, however there is a lack of information on small-scale events due to their magnitude and patchy distribution. To this end, volunteers may provide a useful tool in filling this data gap, especially for coastal environments with a high usage by members of the public. The potential for citizen scientists to record small-scale pollution events is explored using the UK as an example, with a focus on highlighting methods and issues associated with using this data source. An integrated monitoring system is proposed which combines citizen science and traditional reporting approaches.

The present study extrapolates the assessment and characterization of a barely studied region, the Gulf of Kutch, (near Jamnagar), Gujarat, India, in terms of PAH exposure, adverse effects caused by them, and various toxicological indices showing the catastrophic effects of their elevated concentrations. ΣPAH concentration in the site ranged from 118,280 to 1,099,410ngg−1 dw, with a predominance of 2–3-ring PAHs (79.09%) as compared to 4–5- and 6-ring PAHs (20.91%). The concentrations of carcinogenic PAHs were found to be between 8120 and 160,000ngg−1 dw, with a mean of 63,810ngg−1 dw, which is much higher than normal acceptable values. The toxic equivalent quotient for 6CPAHs ranged from 150.47 to 26,330ngg−1 BaPeq, encompassing 50.63% of ΣPAH toxicity. This toxicological profile of the present study site would be of paramount importance as it offers fresh information regarding the load of legacy pollutants such as PAHs and the inputs and methods to cope with their extremely high concentrations in less explored marine habitats.

The aim of this study was to evaluate the post-legislation change in tributyltin (TBT) pollution at Croatian Adriatic coast. Gastropod Hexaplex trunculus and sediments were collected, nearly 10years after TBT based antifouling paints were banned, at 12 locations along the coast where a previous study was conducted in 2005. The study showed a decline of TBT levels over the investigated period, although all gastropods populations were highly affected by imposex meaning that prohibition did not result in the recovery of populations. The further aim was to propose the Ecological Quality Ratio (EQR) boundaries for potential use of H. trunculus as a principal bioindicator in the assessment of the ecological status of the Mediterranean regarding TBT pollution, under the Water Framework Directive (WFD). According to the proposed EQR classes, the WFD target for achieving the Good ecological status of the marine environment by 2015 was not reached.

Seasonal maritime traffic was investigated in relation to cetaceans, through direct observations (July 2013–June 2015) along three fixed transects in Western Mediterranean. Visually obtained vessel abundance was compared with Automatic Identification System data to explore if the two methods provided different results. Traffic intensity and composition were characterised by seasons and vessel categories. Finally, cetacean presence was investigated in relation to traffic by measuring the difference of vessel abundance in the presence and absence of animal sightings. Results showed that visual sampling was consistent with AIS data, providing more information on small-medium vessels. Traffic was more intense and diverse in Spring/Summer, and the highest vessel abundance and seasonal variations in composition emerged for inshore subareas. The difference of traffic in the presence and absence of cetaceans was higher in most offshore subareas in Spring/Summer, verified for B. physalus and S. coeruleoalba; in inshore waters, mostly occupied by T. truncatus, no significant differences emerged.

This study estimated the total loads of plastic litter (macro-meso- and micro-plastics) in sediments from a wide stretch of marine and coastal environment of Tyrrhenian Sea. The prevailing category of debris was microplastic. The results obtained, in terms of average amount of microplastic per kilogram of dry sediment, are in agreement with data reported by various Authors internationally. The study area resulted to be uniform for plastic items levels. Particularly evident was the influence of a flood, occurred in November 2012 in Talamone, on sediments collected at the harbour of this locality: in this area, a difference in levels and quality of plastic debris, attributable to periods before and after the flood, was observed in sediments. In addition to focusing on the effect of this phenomenon, this study gives an important overview, for what concerns the presence of plastic litter, of a significant naturalistic area.

A rapid, simple yet scientifically sound scheme providing two important types of information used in assessment of estuarine sediments is presented. The mean enrichment quotient (MEQ) (fine contemporary sediment metal concentration/fine fraction background metal concentration) for Cu, Pb and Zn provides the magnitude of human-induced change, (deviation from the pristine condition), while sediment quality guidelines (SQGs) assess the risk posed by sedimentary contaminants to the benthic community.Maximum metal enrichment for sediment in Sydney estuary (Australia) is >100 times for Cu, Pb and Zn and the MEQ is >10 times for most of the estuary. Adverse effect on benthic populations due to Cu, Pb and Zn are expected in 2%, 50% and 36% of the waterway, respectively. SQGs for contaminant mixtures predict ~2% of the estuary has the highest risk of adverse effects, while 25% has intermediate risk. The scheme is well suited to initial assessments of estuarine sediments worldwide.

Bottom aquaculture of bivalves is a high-yield culture method, which is increasingly adopted by shellfish farmers worldwide. However, the effects of bottom aquaculture on benthic ecosystems are not well-known. Manila clam (Ruditapes philippinarum), is a widely distributed bottom aquaculture mollusk species. To assess the ecological impacts of Manila clam bottom aquaculture, clams and other macrofaunal assemblages were investigated during four cruises (July and November 2011, February and May 2012) at six sampling sites in Jiaozhou Bay, China. Correlation analysis showed that macrofaunal assemblages had significant negative correlations with the abundance of Manila clams. However, according to the results of several biotic indices, a low disturbance was detected by Manila clam bottom aquaculture. In conclusion, AMBI (AZTI'S Marine Biotic Index) and M-AMBI (Multivariate AZTI Marine Biotic Index) indices are more suitable for assessing ecological quality than polychaete/amphipod ratios when the disturbance is slight, such as at a bivalve bottom aquaculture.