In this study, we report results concerning the accumulation of heavy metals in seawater from Izmit Bay. The bay was divided into the three parts: the eastern, the central and the western basins. The goal of this study was to determine levels of heavy metals at various depths in the bay between April 2008 and May 2010. Liquid–liquid extractions were performed on seawater samples. An atomic absorption spectrophotometer was used to measure levels of six metals: lead, cadmium, chromium, iron, manganese and zinc. We applied our results to evaluate the status of pollution in the Gulf of Izmit. Significant seasonal differences in metal concentrations and higher concentrations of many metals in water near the shore are evidence for uncontrolled release of pollutants in the water.

The distribution of Ruppia cirrhosa meadow density and its epiphytic organisms in relation with environmental factors were studied in summer 2011 at five stations in the Ghar El Melh lagoon (GML; southern Mediterranean Sea). Eleven epiphytic groups were recognised among which diatoms and dinoflagellates were the dominant groups and greatest contributors to temporal dissimilarity. An overwhelming concentrations of harmful microalgae was recorded, mainly represented by the toxic dinoflagellate Prorocentrum lima with maximal concentrations attaining 6×105cells 100g−1 of Ruppia fresh weight. The epifauna community accounted for only 1.4% of total epiphyte abundance and was comprised predominantly of nematodes (47.51%), ciliates (32.59%), fish eggs (7.2%) and larvae (4.95%). PERMANOVA analyses revealed a significant spatio-temporal variation of all epiphytic groups (p<0.01). In this study, R. cirrhosa and its epiphytes were studied as potential early warning indicators of the health status of GML waters.

The total concentrations of twelve, likely carcinogenic, polycyclic aromatic hydrocarbons (PAHs) (i.e., phenanthrene (Phe), anthracene (An), fluoranthene (Fluo), pyrene (Pyr), benz[a]anthracene (B[a]A), chrysene (Chry), benzo[b]fluoranthene (B[b]F), benzo[k]fluoranthene (B[k]F), benzo[a]pyrene (B[a]P), indeno[1,2,3-cd]pyrene (Ind), dibenz[a,h]anthracene (D[a,h]A), and benzo[g,h,i]perylene (B[g,h]P) in backwash deposits of the 2004 Khao Lak tsunami were carefully investigated and compared with the concentrations of world marine sediments (WMS). In general, ∑12PAHs in this study (i.e., 69.43±70.67ngg−1) were considerably lower than those values observed in marine sediments from Boston (54,253ngg−1), coastal sediments from Barcelona Harbour (15,069ngg−1), and riverine sediment from Guangzhou Channel (12,525ngg−1), but were greater than values from coastal sediments in Rosas Bay (12ngg−1), Santa Ponsa Bay (26ngg−1) and Le Planier (34ngg−1). The total toxic benzo[a]pyrene equivalent (TEQCarc) values calculated for Khao Lak coastal sediments (KCS), Khao Lak terrestrial soils (KTS), and Songkhla Lake sediments (SLS) were 10.3±12.2ngg−1, 16.0±47.7ngg−1, and 5.67±5.39ngg−1, respectively. Concentrations of PAHs at all study sites resulted in risk levels that fell into the “acceptable” range of the US EPA model and were much lower than those of other WMS. The cancer risk levels of PAH content in KCS ranged from 7.44×10−8 to 2.90×10−7, with an average of 1.64×10−7±8.01×10−8; this value is 119 times lower than that of WMS. In addition, soil cleanup target levels (SCTLs) for both non-carcinogens (i.e., Phe, An, Fluo and Pyr) and carcinogens (i.e., B[a]A, Chry, B[b]F, B[k]F, B[a]P, Ind, D[a,h]A and B[g,h,i]P) in the KTS samples were estimated for all target groups, with an average value of 115,902±197,229ngg−1.

Bioinvasions are a significant force of change – and economic and ecological threat – in marine ecosystems. The threat now encroaches on Alaska, which has had relatively few invasions compared to other global regions, prompting need to develop new incursion response tools. We appraised five ‘eco-friendly’ immersion treatment options (dilute acetic acid, dilute bleach, freshwater, brine and hypoxia) at either minute- or hour-scale exposures to kill the invasive tunicate Didemnum vexillum. Data revealed 100% treatment efficacy after two minutes in acetic acid, ten minutes in bleach, four hours in freshwater and over four hours in brine solution. We also demonstrated the importance of monitoring D. vexillum recovery for at least three weeks, since seemingly destroyed colonies rebounded during this timeframe. Combined, these findings provide insights towards a bay-scale eradication and post-border management plan applicable to the recent D. vexillum incursion in Whiting Harbor, Alaska and other shallow, inshore invasion sites.

Total organic carbon (TOC), total nitrogen (TN), δ13C and δ15N were measured in sediment cores at three sites in Sishili Bay, China, to track the impacts of anthropogenic activities on the coastal environment over the last 100years. The increased TOC and TN in the upper section of sediment cores indicated a eutrophic process since 1975. In comparison, the TOC and TN in the sediment core near to a scallop aquaculture area displayed a much slower increase, indicating the contribution of scallop aquaculture in mitigating eutrophication. Combined information from δ13C, δ15N and TOC:TN indicated an increased terrestrial signal, although organic matter sources in Sishili Bay featured a mixture of terrestrial and marine sources, with phytoplankton being dominant. Increased fertilizer use since 1970s contributed to the eutrophic process in Sishili Bay since 1975, and increased sewage discharge from 1990s has added to this process.

To investigate fine particulate air pollution generated by public transport and its microenvironment, PM2.5 measurements and particle number counts for six particle size ranges (0.3–0.5 µm, >0.5–1.0 µm, >1.0–3.0 µm, >3.0– 5.0 µm, >5.0–10 µm and >10 µm) were obtained for four public transport modes: bus, metro–bus, car and walking. The measurements were repeated for each transport mode twice a day for 7–10 measurement days. The highest average PM2.5 concentration was measured inside a bus (106 µg/m3) during rush hours. The highest single peak measurement was a concentration of 316 µg/m3 for walking during non–rush hours. The PM2.5 level in a car with the air conditioning fan off was approximately 2.5 times lower than the level with the air conditioning fan on. Moderate correlations were found between PM2.5 concentrations and wind speed. Weak correlations were found between PM2.5 concentrations, relative humidity and temperature. The results showed that the diameters of most of the particles were smaller than 0.5 µm, regardless of the transport mode. The average fine particle number (size range 0.3–0.5) for all transport modes ranged from 54 647 to 209 746 particles/103 cm3 during rush hours and from 49 423 to 184 866 particles/103 cm3 during non–rush hours.

Ambient visibility is a complex manifestation arising out of interactions among many atmospheric variables, including ambient aerosol load, and region specific geophysical characteristics. To functionally relate visibility impairment in Delhi region during winter months-months marred with poor visibility conditions–a novel experiment was designed to relate visibility with ambient aerosol load (PM2.5), and relevant meteorological variables: dew point temperature (Dp), height of planetary boundary layer (PBL), ambient temperature (T), relative humidity (RH), wind speed (WS) and wind direction (WD). Time series data sets of Visibility(t) and other variables were subjected to non–linear decomposition using Empirical Mode Decomposition Method (EMD), enabling to obtain total cyclic and acyclic–trend components embedded in all data–sets. Extracted total cyclic visibility components were functionally related with the corresponding components associated with PM2.5 load and meteorological variables. Decomposed acyclic–trend component of the visibility, representing time dependent acyclic trend (AT), was separately related with the corresponding AT components of the considered meteorological variables. The decomposed components of the visibility (total cyclic and AT) were subjected to multiple linear regression to establish a functional relationship between them and a set of variables among the considered variables. The analysis suggests that acyclic–trend associated with Visibility(t) can be predicted better as opposed to the Visibility(t)cyclic component.

Monitoring ecological variables is mandatory to detect abnormal changes in ecosystems. When the studied variables exceed predefined alert thresholds, management actions may be required. In the past, alert thresholds have been typically defined by expert judgments and descriptive statistics. Recently, approaches based on statistical power were also used. In New Caledonia, seagrass monitoring is a priority given their vulnerability to natural and anthropic disturbances. To define a suitable monitoring strategy and alert thresholds, we compared a Percentile Based Approach (PBA) and a sensitivity analysis of power (SAP). Both methods defined statistically relevant alert thresholds, but the SAP approach was more robust to spatial and temporal variability of seagrass cover. Moreover, this method characterized the sensitivity of threshold values to sampling efforts, a useful knowledge for managers.

The most important oyster farming area in Europe is in a close proximity of two medium size merchant ports. Cargo ships deballast in this area before loading, releasing unwanted or noxious marine species. During a sampling campaign aboard these arriving ships, we found in some ballast water samples a huge number of potentially toxic dinoflagellates and some potentially pathogenic bacteria. A model was applied to find the potential geographical spread of the discharged ballast water. This model predicts the water to reach highly vulnerable shellfish farmed areas in six to eight days.

The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in mullet (Liza klunzingeri), water and sediment from northern part of Hormuz strait (Persian Gulf). The concentration levels of total PAHs in L. klunzingeri, water and sediment were 133.99–268.57ngg−1dry weight, 3.12–5.88ngl−1 and 42.29–228.9ngg−1 dry weight, respectively. Based on isomer ratios, analysis of the PAHs source in the sediment demonstrated that the PAHs come from pyrogenic and petrogenic origin. Risk assessment showed PAHs threshold concentrations to occasionally be exceeded in the study area.