Nitrogen isotope ratios (δ15N) in juvenile winter flounder, Pseudopleuronectes americanus, were used to examine changes in nitrogen inputs to several Rhode Island, USA estuarine systems. Fish were collected over two three-year periods with a ten-year interval between sampling periods (2002–2004 and 2012–2014). During that interval numerous changes to nutrient management practices were initiated in the watersheds of these estuarine systems including the upgrade of several major wastewater treatment facilities that discharge to Narragansett Bay, which significantly reduced nitrogen inputs. Following these reductions, the δ15N values of flounder in several of the systems decreased as expected; however, isotope ratios in fish from upper Narragansett Bay significantly increased. We believe that low δ15N values measured in 2002–2004 were related to concentration-dependent fractionation at this location. Increased δ15N values measured between 2012 and 2014 may indicate reduced fractionation or that changes in wastewater treatment processes altered the nitrogen isotopic ratios of the effluents.

Recovery of vegetation on a Long Island, NY salt marsh was investigated after the removal of hurricane-deposited large wooden debris through managed clean-ups involving volunteers. Two years after the removal of the debris, vegetation cover and species composition were not significantly different from controls. There was no significant difference in vegetation recovery among fall and spring debris removal treatments. Initial vegetation cover of the experimental and control plots was 95.8% and 1.2%, respectively; after two growing seasons cover was 78.7% and 71.2%, respectively. The effects of trampling by volunteers during debris removal were monitored and after one growing season, trails used during a single clean-up effort had a mean vegetation cover of 67% whereas those that were used during multiple clean-up efforts had only 30% cover. We use the results of this study to offer guidance for organizing effective salt marsh clean-up efforts.

To determine sources of organic material in semi-enclosed Bohai Sea, samples of marine surface sediments, suspended particulates in adjacent rivers and atmospheric deposition were collected and analyzed for grain size composition, total organic carbon(TOC and POC), total nitrogen (TN and PN), and stable isotopic composition (δ13C and δ15N). Measured bulk C/N ratio (5.50–12.28), δ13C (−23.59~−19.54‰), and δ15N (2.80–8.07‰) values of surface sediment organic materials indicated a mixed source of marine and terrestrial contributions. Spatial distribution of organic C, N and their stable isotope composition indicated a land-sea gradient of organic material content and source combination. Using MixMIR model with dual isotopes, it was estimated that relative contributions of marine, riverine, and atmospheric sources to sediment mixture were 69.0%, 9.6%, and 21.4%, respectively. Our results demonstrated the advantage of Bayesian isotope mixing models over the conventional end-member mixing models for source apportionment in coastal seas with complex source origins.

An integrated analysis has been carried out using surface sediment monitoring data in order to characterize the spatial distributions and temporal trends of heavy metals within ten years from 2004 to 2013 in the entire Liaodong Bay. Hg, Cd and As were predominant contaminants with their median concentrations of 0.04–0.15, 0.01–0.65, and 1.80–30.3mg/kg respectively. Both areas and levels of Cu and Pb contamination were low. Cd contents exhibited an obvious decreasing trend and As presented a similar law during these 10years. Further, emissions from different sources were analyzed to identify the possible reasons contributing to the metal pollution. Dramatic descending of waste water might be the top reason for Cd and As variations. Local flue gases and smoke emissions might not be the main sources contributing to Hg pollution, whereas atmospheric deposition at a larger scale was supposed to be the leading factor.

A study had been carried out to determine Cu, Zn, Cd, Hg and Pb concentrations in the muscle and fins of four elasmobranchs species namely spot-tail sharks, milk sharks, whitespotted bamboo sharks and whitespotted guitarfish from Pulau Kambing LKIM Fishery Complex, Kuala Terengganu, Malaysia. Zinc level was found to have the highest concentration whereas Cd had the lowest concentration in both organs. By comparing both organs, metals concentrations in fins of all elasmobranchs species were higher than muscle. Result obtained was compared with the guidelines set by Malaysian Food Regulation and the provisional tolerable weekly intake was also determined. Current study recommends that the muscle of whitespotted bamboo shark from Kuala Terengganu Waters is likely not to be consumed due to it exceeded the allowable consumption guideline. Finding of this paper is very useful as it provides the baseline data on the pollution status of elasmobranchs in Kuala Terengganu Waters.

Mussels (Mytilus spp.) are worldwide utilized in marine biomonitoring by a multi-biomarker approach. However, for a correct interpretation of different biomarker responses, information is needed on their natural seasonal variability due to environmental/physiological factors.In this work, the seasonal variations of different biomarkers were investigated in M. galloprovincialis from 4 different sites from the gulf of La Spezia (Ligurian sea, Italy), an intensive rearing area in the north-western Mediterranean near La Spezia harbor, an important commercial and touristic port. Lysosomal membrane stability-LMS, stress on stress-SoS, phagocytosis, tissue metallothionein-MT content, oxidative stress related enzyme activities (GST, catalase), and nitric oxide (NO) production were evaluated. The results underline the importance of LMS and SoS as core descriptors of the mussel health status in relation to seasonal variations in temperature and reproduction. These data represent the baseline information for ongoing biomonitoring studies related to dredging activities in this area.

Black bream (Acanthopagrus butcheri) were collected from an artificial inlet, Claisebrook Cove, Western Australia. Claisebrook Cove is adjacent to an historic contaminated site that was remediated during the 1990s. It was later identified as a priority area due to elevated levels of sediment contaminants including Zn, Cu, and Pb. Black bream were collected from this cove in 2005 and 2012 and their otoliths were analysed by laser ablation inductively coupled plasma mass spectrometry of the most recent growth zone. Levels of Zn and Mn, which are metabolically regulated, did not correlate with sediment contamination. However, reduction in sediment Cu levels over time coincided with reduced Cu otolith levels from 2005 to 2012. Results indicate that the elemental composition of the marginal edge of Black bream otoliths can identify bioavailable contaminants in an urban estuary and, with monitoring, can be utilized to establish long-term trends.

Acid rain is a serious environmental problem in China, caused by the urbanization and industrialization. We used recent acid rain and urban pollutant emissions data from the eastern coastal Jiangsu province to analyze the spatial distribution of acid rain. Further, we analyzed the regional air pollution data of the commission discharge atmospheric research database (EDGAR) regional air pollution data and developed a back-trajectory model for the cluster analysis of the air mass transfer characteristics of acid rain. The results show that from 2007 to 2013 the precipitation pH were high in northern and low in southern parts of Jiangsu Province. The average precipitation pH in the northwest and northeast parts were higher than 5.6; the frequency of acid rain in the area south of the Huaihe River accounted for more than 50% of total rainfall samples. Precipitation conductive in the northwest and southwest was greater than 60 μs/cm. The SO2, NOX, and PM10 were lower in the northern part and higher in the southern part. The northern part has higher pH and lower emission of precursors. One likely source for high ammonium and calcium concentration is local soil. From the northwest air mass, the acid rain appeared to have the highest average pH and the air mass from the southwest had the highest percentage of acid rain. The local emission (SO2, NOX, and Dust) reduction from 2005 led the haze and the acid rain problems mitigated to a good trend. The haze day increase and acid rain decrease due to the NH4+, and Ca2+ increase, and the long-distance transmission and the alkaline pollutant played an important role in Jiangsu' acid rain problem and haze since 2009.

Here we present the large-scale distribution of microplastic contamination in beach sediment across Europe. Sediment samples were collected from 23 locations across 13 countries by citizen scientists, and analysed using a standard operating procedure. We found significant variability in the concentrations of microplastics, ranging from 72±24 to 1512±187 microplastics per kg of dry sediment, with high variability within sampling locations. Three hotspots of microplastic accumulation (>700 microplastics per kg of dry sediment) were found. There was limited variability in the physico-chemical characteristics of the plastics across sampling locations. The majority of the microplastics were fibrous, <1mm in size, and blue/black in colour. In addition, using Raman spectrometry we identified particles as polyester, polyethylene, and polypropylene. Our research is the first large spatial-scale analysis of microplastics on European beaches giving insights into the nature and extent of the microplastic challenge.

This study focuses on creating baseline for 238U, 235U, 234U, 210Pb, 210Po and 40K concentrations in the northern Arabian Gulf. The respective concentration ranges were 0.047–0.050, 0.00186–0.00198, 0.054–0.057, 0.00085–0.00092, 0.00051–0.00062 and 18.6–19.1Bql−1. These results suggest that the levels are generally comparable to other marine waters in the northern hemisphere. There were no hot spots observed from oil and gas industry. These data will serve as a baseline to gauge possible future inputs of TENORMs in the northern Gulf. A positive and linear correlation was observed between 238,234U, 40K isotopes and seawater salinity. The results also suggest significant fractionation between 210Po and 210Pb, attributed to rapid removal of 210Po by biota compared to 210Pb. The mean residence time for 210Po in the study area was 371days. The 234U/238U and 238U/235U activity ratios in seawater samples vary between 1.14–1.15, and 0.038–0.040. The 234U/238U and 235U/238U ratio is similar to the expected composition of seawater (1.148±0.002) and 0.0462.