To explore the genetic diversity and paralytic shellfish poisoning (PSP) toxin profile of the Alexandrium tamarense species complex along the coast of China, 67 strains of A. tamarense from the China Sea were collected and genetic diversity were analyzed based on the rDNA sequences. In addition, PSP toxin compositions and contents were detected by HPLC. According to the 5.8S rDNA and ITS, and LSU rDNA D1–D2 sequence, A. tamarense in the China Sea comprises at least Group IV and Group I ribotypes. In these Chinese strains, the toxins with the highest concentration in the profile were C1/2, gonyautoxins 1/4 (GTX1/4) and neosaxitoxin (NEO). However, the toxin profiles were atypical and C1/2 toxins were not detected in some strains. No strict correlation was observed between the PSP toxins profile and the geographical distribution.

Most land-based debris enters the ocean via rivers during the rainy season. The Nakdong River system, the largest river entering the South Sea of Korea, discharges 3000tons of debris per year. We deployed small tracking buoys with satellite location transmitters to monitor river-borne floating debris movement. The buoys moved for various distances depending on the change in flux in different regions. A hot spot was expected to contain a large accumulation of floating debris. The central and lower parts of the eastern downstream region were identified as important regions. The results of this study provide information related to the movement of debris that can be used when establishing a method for collection of floating debris from rivers and streams. The study contributes to efforts to decrease the amount of floating debris in oceans and the costs associated with debris removal by improving the effectiveness of preventative measures.

Temperature changes due to climate change and seasonal fluctuation can have profound implications on chemical toxicity to marine organisms. Through a comprehensive meta-analysis by comparing median lethal or effect concentration data of six chemicals for various saltwater species obtained at different temperatures, we reveal that the chemical toxicity generally follows two different models: (1) it increases with increasing temperature and (2) it is the lowest at an optimal temperature and increases with increasing or decreasing temperature from the optimal temperature. Such observations are further supported by temperature-dependent hazardous concentration 10% (HC10) values derived from species sensitivity distributions which are constructed using the acute toxicity data generated at different temperatures. Considering these two models and natural variations of seawater temperature, we can scientifically assess whether applying an assessment factor (e.g. 10) to modify water quality guidelines of the chemicals can adequately protect marine ecosystems in tropics, subtropics and temperate regions, respectively.

Composition and abundance of persistent buoyant litter (plastics, polystyrene and manufactured wood) were investigated at riversides and on adjacent coastal beaches of four rivers flowing into the SE Pacific Ocean. Persistent buoyant litter made up the main share of litter at riversides (36–82%) and on coastal beaches near the river mouths (67–86%). The characteristic litter composition of each river is attributable to human influences along its course. Riverine litter items were deposited to both sides of the river mouths on coastal beaches, and their abundance generally declined with distance from the river mouth. However, maximum litter accumulations were often found on beaches north of the river mouth, suggesting a long-term influence of the prevailing equatorward low-level jet along the Chilean coast. The results confirm that riverine transport has an important impact on litter abundances on coastal beaches.

An oil spill model is developed and coupled to a current-wave model to simulate oil spill transport in aquatic environments where waves are present. The oil spill model incorporates physical–chemical processes of oil spill, and simulates oil slick transport by a circulation-driven Lagrangian Parcel model. Using the coupled oil spill model and the current-wave model CH3D-SWAN, a laboratory observed wave induced circulation and oil slick evolution are successfully simulated, while different current-wave coupling schemes generate different flow patterns and oil slick evolution. The modeling system is also shown to simulate Langmuir circulation and resulting oil slicks. Hypothetical scenarios of oil spill near Virginia coast during Hurricane Isabel and Irene are simulated using the oil spill model and the CH3D-Storm Surge Modeling System to assess the role of storm waves during oil spill. The spill area is significantly larger when storm waves are considered, implying waves significantly increase oil spill dispersion.

The partitioning and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matter (SPM), and fish samples from the Dongjiang River (DR), Pearl River (PR), and the Pearl River Estuary (PRE) were examined. Although PAHs are much lower in PRE than in DR or PR, PAHs in some fish species are significantly higher in PRE than in DR or PR. Aqueous or particulate PAHs respectively show significant correlations with dissolved organic carbon, particulate organic matter, and chlorophyll a, suggesting that biological pumping effect regulates their distribution. The in situ partitioning coefficients (logKoc) for PAHs are one order magnitude higher than the empirical logKoc–logKow correlation. The bioconcentration factor (BCF) is slightly higher for the marine fish than for the freshwater fish. The above phenomena indicate that BCF may vary due to the diversity of fish species, feeding habits, and metabolism of PAHs in fish.

In this paper we present the concentrations of Hg, Cd, Se, Pb, Cu, Mn, Zn and Fe in organs of 6 non-common specimens of cetaceans that were stranded along the Israeli Mediterranean coast (IMC), during 2002–2010: two fin whales, one minke whale, one Cuvier’s beaked whale, one rough-toothed dolphin, and one Risso’s dolphin. Most of the specimens were calves stranded by accident. Concentrations of Hg and Cd were low in tissues of the baleen whales and higher in the toothed whales, with maximum concentrations of 1067mgkg−1 Hg in the liver of the Risso’s dolphin and 29mgkg−1 Cd in the kidney of the Cuvier’s beaked whale. As far as we are aware, this is the first report of trace elements in baleen whales in the Eastern Mediterranean, and the first report of trace elements in minke whale and rough-toothed dolphin in the Mediterranean.

Recently compiled databases facilitated estimation of basin-wide benthic organic biomass and turnover in the Strait of Georgia, an inland sea off western Canada. Basin-wide organic biomass was estimated at 43.1×106kgC and production was 54.6×106kgCyr−1, resulting in organic biomass turnover (P/B) of 1.27×yr−1. Organic biomass and production for sub-regions were predictable from modified organic flux (r2>0.9). P/B declined significantly with increasing modified organic flux, suggesting greater biomass storage in high flux sediments. Biomass and production were highest, and P/B lowest near the Fraser River. Annual basin-wide benthic production was 60% of previously estimated oxidized organic flux to substrates, which agrees with proportional measurements from a recent, localized study.Deviations from expected patterns related to organic enrichment and other stressors are discussed, as are potential impacts to benthic biomass and production, of declining bottom oxygen, increasing bottom temperature and potential changes in riverine input.

224Ra and 223Ra are adopted as tracers to qualify submarine groundwater discharge (SGD) in Tolo Harbor, a highly urbanized embayment in Hong Kong. Based on the sampling data, a two-layered radium mass balance model is used to estimate lateral SGD and bottom SGD. Total SGD is estimated to be 1.2–3.0cmd−1, including lateral SGD of 5.7–7.9cmd−1 and bottom SGD of 0.3–2.0cmd−1. Fresh SGD is estimated to be (2.1–5.5)×105m3d−1. Nutrient fluxes (mold−1) from SGD are estimated to be (3–7.4)×104 (dissolved inorganic nitrogen), (2.4–6.2)×102 (dissolved inorganic phosphate) and (6.5–16)×104 (dissolved silicate). Primary productivity is estimated to be (1.5–15)×106gCd−1, 2–53% of which is supported by SGD-induced phosphate fluxes. The study indicates that SGD is a significant source of nutrients to coastal waters and may cause an obvious increase of primary production. These findings must be considered in future coastal ecological management.

Environmental samples (seawater, sediments and biota) were collected along the eastern and western Indonesian coasts between 2011 and 2013 to anticipate the possible impacts of the Fukushima radioactive releases in Indonesia. On the eastern coasts (south and north Sulawesi), the 137Cs concentrations in the seawater and sediments were 0.12–0.32Bqm−3 and 0.10–1.03Bqkg−1, respectively. On the western coasts (West Sumatra, Bangka Island, North Java, South Java and Madura island), the 137Cs concentrations in the seawater and sediments were 0.12–0.66Bqm−3 and 0.19–1.64Bqkg−1, respectively. In general, the 137Cs concentrations in the fish from several Indonesian coasts were <MDA – 109.75mBqkg−1. In contrast, the 137Cs concentrations in mollusk, crab and prawn were 10.65–38.78, 4.02 and 6.16mBqkg−1, respectively. 134Cs was not detected in the seawater, sediments or biota. Thus, it was concluded that 137Cs on the eastern and western Indonesian coasts originated from global fallout.