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Although substantial enrichment of suspended matter gets flushed out of the estuary during monsoon, there is a net PAE accumulation in the estuary during post-monsoon following an increased sedimentary restitution. Data of PAEs generated herein raises a challenge for immediate enactment of statutory legislation to curb and regulate hazardous contamination of estuaries by phthalic acid esters.To understand the status of the radionuclides released during the Fukushima Dai-ichi Nuclear Power Plant accident, the 134Cs, 137Cs and 90Sr in the seawater in the public area of the northwest Pacific Ocean were analyzed in November-December 2012. The radioactivity of 134Cs, 137Cs and 90Sr decreased sharply from June 2011 to November-December 2012. The highest average values of 134Cs and 137Cs were found at a depth of 500 m, suggesting that 134Cs and 137Cs had been transported to a depth of 500 m or deeper by the end of 2012. Total inventories of 0.80 ± 0.20 pBq for 137Cs from the surface to a depth of 500 m and 0.07 ± 0.02 pBq for 90Sr from the surface to a depth of 100 m were obtained in the waters southeast of Fukushima. 134Cs was detectable in the Chinese exclusive economic zone, and the seawater quality was much lower than the target level for China.The studies of the formation of oil-Suspended Particulate Matter (SPM) aggregates (OSAs) have advanced significantly in the scientific community, however there is a need to accelerate oil biodegradation that was dispersed by the formation of OSAs. The present research presents a pioneering character regarding the addition of nutrients as biostimulus for autochthonous hydrocarboclastic bacteria in the biodegradation of Total Petroleum Hydrocarbons (TPH) dispersed by the formation of OSAs. Water aliquots were taken over 60 days from eight bioreactors to perform ionic species analysis, pH, salinity and temperature monitoring, liquid/liquid extraction, serial dilution methodology and filter membrane. https://www.selleckchem.com/products/Etopophos.html TPH quantification was performed on the gas chromatograph with a flame ionisation detector (GC-FID). The addition of nutrients contributed positively to the rate and extent of biodegradation of TPH in association with field-collected SPM. The best result found was with the lowest nutrient concentration (Bio 1) with an average of 98.65% of TPH reduction.The explosive growth of phytoplankton under favorable conditions in subtropical coastal waters can lead to water discolouration and massive fish kills. Traditional water quality monitoring relies on manual field sampling and laboratory analysis of chlorophyll-a (Chl-a) concentration, which is resources intensive and time consuming. The cloudy weather of Hong Kong also precludes using satellite images for algal blooms monitoring. This study for the first time demonstrates the use of an Unmanned Aerial Vehicle (UAVs) to quantitatively map surface water Chl-a distribution in coastal waters from a low altitude. An estimation model for Chl-a concentration from visible images taken by a digital camera on a UAV has been developed and validated against one-year field data. The cost-effective and robust technology is able to map the spatial and temporal variations of Chl-a concentration during an algal bloom. The proposed method offers a useful complement to traditional field monitoring for fisheries management.This study covers water and sediment chemical characteristics by the western shore of Admiralty Bay (King George Island, Antarctica) in 2016. Chemical processes between sediment and water have been described based on the determination of ions, metals, non-metals, and TOC concentrations. Rock weathering is an important source of Fe, Ni, Co, Al in the seashore area. The PCA shows the impact of acidification in the release metals from sediment. Our results indicate that riverine mineral fluxes need to be accounted for as the volume of melt increases in response to climate change. Based on geoaccumulation indexes (anthropogenic fingerprint), we observed an increased concentration of Pb (Igeo = 1.643), in the lake near station facilities and Cd in the area of Ecology Glacier (Igeo > 1.389). Taking into account climate change and the intensification of anthropopressure, our study indicates that Antarctica requires a special focus on the seasonal dynamics of mineral content and pollution assessment.Intensification of lateritic nickel mining in Southeast Asia and Melanesia potentially threatens coastal ecosystems from increased exposure to nickel and suspended sediment. link2 This study investigated the response of Acropora muricata when exposed to either dissolved nickel, clean suspended sediment or nickel-contaminated suspended sediment for 7 days, followed by a 7-d recovery period. Significant bleaching and accumulation of nickel in coral tissue was observed only after exposure to high dissolved nickel concentrations and nickel-spiked suspended sediment. No effect on A. muricata was observed from exposure to a particulate-bound nickel concentration of 60 mg/kg acid-extractable nickel at a suspended sediment concentration of 30 mg/L TSS. This study demonstrates that bioavailability of nickel associated with suspended sediment exposure plays a key role in influencing nickel toxicity to corals. These findings assist in assessments of risk posed by increasing nickel mining activities on tropical marine ecosystems.Discharge of grey water from ships is today unregulated in most sea areas, including the Baltic Sea. Annually, an estimated 5.5 million m3 grey water is emitted to the Baltic Sea with largest contribution from RoPax (4.25 million m3) and cruise ships (0.65 million m3). In total 44 different contaminants in grey water was identified and sorted into the sub categories organic compounds (28) and metals (16). Zinc and copper had the highest average concentrations with yearly inputs of 2.8 tons (zinc) and 1.5 tons (copper). 159 tons of nitrogen and 26.4 tons of phosphorus were estimated to be discharged to the Baltic Sea annually. An environmental risk assessment of contaminants, performed at a shipping lane in the Baltic Sea, showed the risk for adverse effects from grey water to be low. Nitrogen and phosphorus input from grey water contributes to 0.25% of the exceedance of, for the Baltic Sea set, eutrophication target.Microplastics are ubiquitous in our environment, yet we have little knowledge on their accumulation profile and changing trend. In this study, we selected the semi-enclosed Jiaozhou Bay as the research area to study the vertical distribution characteristics of microplastic in the sediment and analyzed factors that might affect this distribution pattern. We found six different polymer types and the microplastic abundance ranged between 2.5 items/kg d.w.-27.5 items/kg d.w.. Microplastic abundance was very low in deep sediment and generally showed a decreasing trend from the surface down with some shifts at different depth at certain sites. Based on our data, the total microplastics in the sediment were estimated to reach 3.71 tons in Jiaozhou Bay. This study shows that the vertical microplastic abundance profile in the sediment can not only show the microplastics pollution level but also reflect environmental factors and anthropogenic impacts.It remains challenging to identify nitrate sources in streams due to complications associated with anthropogenic inputs and in-stream biogeochemical processes. We used dual isotopic analysis of nitrate and a Bayesian isotope mixing model to explore the dynamics of nitrate sources and their associated transformations among three types of headwater watershed with different dominant land use types during four seasons in Jiulong River Watershed, a coastal China watershed. Nitrogen sources were the primary determinant of the δ15N-NO3 and seasonal differences in biogeochemical processes exhibited among watersheds. Nitrate was mostly derived from nitrification in spring and summer, whereas atmospheric deposition greatly influenced the isotopic composition in autumn and winter. Chemical fertilizer contributed the largest to the riverine nitrate, accounting for 36.9 ± 12.3%, followed by soil N (27.2 ± 4.4%), atmospheric deposition (23.9 ± 11.8%) and manure & sewage (12.0 ± 5.9%). This study reveals the seasonality of riverine nitrate sources under changing watershed land use patterns.In this study, we characterized plastic debris (PD) found on beaches from Concepción Bay in central Chile during spring 2017 and summer 2018. The identification of polymers was carried out using FT-IR. link3 Persistent organic pollutants (POPs) were extracted with hexane using an ultrasonic bath and further quantified through GC-MS. The highest abundance of PD was obtained during the summer (4.1 ± 3.7 items/m2), with the most common size range between 2.5 and 10 cm (42%) and the most frequent shape were plastic fragments (44%). FT-IR analysis showed that polypropylene was the most recurrent plastic polymer found. The ∑10PBDEs ranged from 2.1 to 1300 ng/g in spring 2017 and 392 to 3177 ng/g in summer 2018. ∑7PCBs ranged from 0.9 to 93 ng/g during the spring 2017 and 0.3 to 4.5 ng/g for summer 2018. This study is the first with information on POPs occurrence in the plastic debris of central Chile.Baseline characterizations of estuarine sediments in Chukchi and Beaufort Seas, were conducted. Concentrations of 194 organic and elemental chemicals were analyzed in sediment and fish, plus stable isotopes of carbon and nitrogen. The estuaries are shallow embayments, with little shoreline relief. The water columns were turbid, high salinity, and not stratified. Concentrations of arsenic and nickel were elevated throughout the region. Arsenic in fish tissue was elevated. Concentrations of PAHs were relatively high for pristine locations, but did not include petroleum hydrocarbons. Characteristics of PAHs indicate large contributions of terrestrial organic matter. With the exception of Peard Bay, all the estuaries reflected the strong influence of terrestrial plant input with low δo/oo values for carbon and nitrogen. Chlorinated pesticides and PCBs were uniformly low, but detectable in fish tissue. PCB and cyclodiene concentrations were half that seen in southeast Bristol Bay. Hexachlorobenzene was detected in all fish samples.We investigated differences in the feeding habits of the starspotted smooth-hound, Mustelus manazo, in Tokyo Bay between the mid-1990s (low stock size) and the late 2000s (high stock size). The frequency of M. manazo with empty stomachs increased from 5.9% in the mid-1990s to 16.1% in the late 2000s. A decrease in the relative weight of the stomach contents was evident from the mid-1990s to the late 2000s, especially in the small size classes, along with changes in the species composition in the stomach contents. Although crustaceans were the main constituents of the stomach contents, the proportion of crabs increased while those of shrimps and hermit crabs decreased. Changes in the feeding habits of M. manazo may be associated with shifts in the benthic community structure in Tokyo Bay.Ciguatoxins are natural compounds produced by benthic dinoflagellates Gambierdiscus and Fukuyoa spp., which cause fish intoxication by ciguatera fish poisoning. This study aimed to assess the dietary exposure effects of ciguatoxin P-CTX-1 on the reproductive performance in marine medaka (Oryzias melastigma). Fish which ingested >1.16 pg·day-1 for 21 days exhibited abnormal behaviors including diarrhea, abnormal swimming, loss of appetite and decreased egg production. After 7-day exposure to P-CTX-1 at a dose of 1.93 pg·day-1, significant gender-specific differences in reproductive performance and decreased hatching rate of the offspring were observed. Chemical analysis of P-CTX-1 showed that the P-CTX-1 accumulation rates were 24.1 ± 1.4% in female fish and 9.9 ± 0.4% in male fish, and 0.05 pg·egg-1 was detected. The results illustrate that dietary exposure to P-CTX-1 affected the reproductive performance and survival of offspring, and caused bioaccumulation and maternal transfer of P-CTX-1 in marine medaka.