The Burullus Lagoon north Nile Delta of Egypt is a UNESCO-protected area. Recently it has become a sediment sink which led to shrinking in its area and depth accompanying with increasing contaminant levels. In this study we attempt to explore the spatial distribution and their mobility of heavy metals (Zn, Cu, Ni, Cr and Pb) based on 21surface sediment samples recovered from Burullus lagoon basin and nine drains. The risk assessment code of the studied heavy metals can be arranged as Zn>Cu>Pb>Cr>Ni for all the samples collected from the lagoon basin and nine different drains. The heavy metals tend to accumulate in fine sediments and human activities promote the accumulation of contaminated sediments in water courses.

Rapid assessment sampling for target species is a fast cost-effective method aimed at determining the presence, abundance and distribution of alien and native harmful aquatic organisms and pathogens that may have been introduced by shipping. In this study, the method was applied within a large tropical port expected to have a high species diversity. The port of Kaohsiung was sampled for bivalve molluscan species that attach using a byssus. Such species, due to their biological traits, are spread by ships to ports worldwide. We estimated the abundance and distribution range of one dreissenid (Mytilopsis sallei) and four mytilids (Brachidontes variabilis, Arcuatula senhousa, Mytilus galloprovincialis, Perna viridis) known to be successful invaders and identified as potential pests, or high-risk harmful native or non-native species. We conclude that a rapid assessment of their abundance and distribution within a port, and its vicinity, is efficient and can provide sufficient information for decision making by port managers where IMO port exemptions may be sought.

Strong winds and storm surges from Typhoon Haiyan caused damage of US$12–15billion and >10,000 human casualties in central Philippines in November 2013. To validate a proposed government US$22million mangrove replanting program, mangrove damage and short-term recovery were surveyed in seven natural and planted mangrove sites in Eastern Samar province at 2.5month and 4.5month post-Haiyan. The preliminary assessment showed that natural mangroves (except for those directly hit by the storm) were recovering by means of tree sprouts and surviving seedlings and saplings compared to the devastated plantation. Likewise, tree mortality was higher in the plantation and natural forests hit by the storm surge, compared to more undamaged and partially damaged trees in natural mangroves. Hence the main recommendations to government are (1) to protect recovering mangroves by not releasing rehabilitation funds (that will inadvertently pay for clearing of live trees and for removal of seedlings), (2) to only plant in totally damaged sites (e.g., plantations), and (3) to only plant naturally dominant species, e.g., Sonneratia alba and Avicennia marina (instead of the popular Rhizophora apiculata, R. mucronata and R. stylosa).

The sampling effort for detecting taxonomic distinctness of periphytic diatom communities was studied in coastal waters of the Yellow Sea, northern China, from May to June 2014. Samples with different sizes (microscopy glass slides) were collected at two depths of 1m and 3m. To obtain the communities with dissimilarities of <10%, 2 slide replicates were sufficient for sampling at a depth of 1m, while 4 were required for the those at a depth of 3m. The values of four taxonomic distinctness indices represented a low sensitivity to sample sizes over all exposure period ages: at a coefficient of variation of <10%, 2 and 9 slide replicates were required at a depth of 1m and 3m, respectively. We suggest that the sampling strategy of the diatoms for detecting taxonomic distinctness might be better at 1m than at a deeper layer in coastal waters.

Oil biodegradation at a simulated depth of 1500m was studied in a high-pressure apparatus at 5°C, using natural seawater with its indigenous microbes, and 3ppm of an oil with dispersant added at a dispersant:oil ratio of 1:15. Biodegradation of the detectable hydrocarbons was prompt and extensive (>70% in 35days), although slower by about a third than under otherwise identical conditions equivalent to the surface. The apparent half-life of biodegradation of the total detectable hydrocarbons at 15MPa was 16days (compared to 13days at atmospheric pressure), although some compounds, such as the four-ring aromatic chrysene, were degraded rather more slowly.

One of the more important steps in understanding the ecosystem-level effects of anthropogenic disturbances on resident species is developing an accurate representation of the lethal and sub-lethal effects of these stressors. We develop methods for describing the impacts of oil on growth and mortality rates in fishes. We conducted a literature search to determine potential relationships between direct and indirect effects of exposure to oil, based on the frequency of lesions and body growth reduction. Data examining these effects with different exposure mediums were assessed and then input into four potential response models (a linear, step-wise, hockey-stick, and exponential model). We assessed the models using the Akaike Information Criterion. The most parsimonious and best fit model was the hockey-stick. This analysis will aid in identifying where future research on the impact of oil on fish should focus and also aid the development of ecosystem models on impacts of oil spills.

Polycyclic aromatic hydrocarbons (PAHs) were investigated in the marine ecosystem of the Daya Bay, South China. The PAH concentrations ranged from 340 to 710ng/g dry weight in the sediments and from 110 to 520ng/g wet weight in marine organisms, respectively. The dominant compounds were three- and four-ring PAHs in the sediments (53%–89%) and two- and three-ring PAHs in the marine species (67%–94%), respectively. PAHs mainly originated from both pyrolytic and petrogenic sources. Comparison with the effects-based sediment quality guideline values suggested that the ecological risk caused by the total PAHs was relatively low (less than 25% incidence of adverse effects) in the sedimentary environment. The median cancer risk level via seafood consumption (1.6×10−5 for urban residents and 1.2×10−5 for rural residents, respectively) was slightly higher than the maximum admissible level (10−5) set by US EPA, but lower than the priority risk level (10−4).

Polycyclic aromatic hydrocarbons (PAHs) and linear alkylbenzenes (LABs) were used as anthropogenic markers of organic chemical pollution of sediments in the Selangor River, Peninsular Malaysia. This study was conducted on sediment samples from the beginning of the estuary to the upstream river during dry and rainy seasons. The concentrations of ƩPAHs and ƩLABs ranged from 203 to 964 and from 23 to 113ngg−1 dry weight (dw), respectively. In particular, the Selangor River was found to have higher sedimentary levels of PAHs and LABs during the wet season than in the dry season, which was primarily associated with the intensity of domestic wastewater discharge and high amounts of urban runoff washing the pollutants from the surrounding area. The concentrations of the toxic contaminants were determined according to the Sediment Quality Guidelines (SQGs). The PAH levels in the Selangor River did not exceed the SQGs, for example, the effects range low (ERL) value, indicating that they cannot exert adverse biological effects.

Polycyclic aromatic hydrocarbons (PAHs) were determined in the surface sediments and in the sea cucumbers (Holothuria leucospilota and Stichopus hermanni) from around six Islands in the northern parts of Persian Gulf. The ranges of the average concentrations of PAHs in surface sediments, H. leucospilota and S. hermanni were 10.33–186.16ngg−1 dw, 12.49–505.44ngg−1 dw and 8.08–389.39ngg−1 dw, respectively. The spatial distribution of PAHs reveals that pollutant concentration is relatively higher at the western parts of Persian Gulf. International sedimentary quality guidelines (TEL-PEL) indicated a low probability of harmful effects to benthic organisms. PAH source identification showed that the PAHs in the sediments come from pyrogenic and mixed origin.

The total concentrations and chemical partitioning of Ni, V and Fe have been assessed in surface sediments from 160 sites along the Shadegan wildlife refuge. The results showed that the average total level of Ni, V and Fe in surface sediments were 45.08±12.09, 25.25±20.8 and 25,979.01±6917.91μg/g dw, respectively. On the average, the chemical speciation of Ni, V and Fe in most stations were in the order of residual>oxidisable-organic>acid-reducible>exchangeable. In all fractions, the residual was accounted the highest proportion for the metals analyzed. Among the non-residual phases, the proportion of heavy metals in organic matter fraction was higher than other phases collected from all locations. The comparison between measured values in this study and some fresh water sediment quality guidelines indicated that the levels of nickel would be expected to sporadically cause harmful biological impacts on biota in the Shadegan wildlife refuge.