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Influence of anthropogenic activities on PAHs in sediments in a significant gulf of low-latitude developing regions, the Beibu Gulf, South China Sea: Distribution, sources, inventory and probability risk Full text
2015
Li, Pingyang | Xue, Rui | Wang, Yinghui | Zhang, Ruijie | Zhang, Gan
Fifteen polycyclic aromatic hydrocarbons (PAHs) in 41 surface sediment samples and a sediment core (50cm) from the Beibu Gulf, a significant low-latitude developing gulf, were analyzed. PAHs concentrations were 3.01–388ngg−1 (mean 95.5ngg−1) in the surface sediments and 10.5–87.1ngg−1 (average 41.1ngg−1) in the sediment core. Source apportionment indicated that PAHs were generated from coke production and vehicular emissions (39.4%), coal and biomass combustion (35.8%), and petrogenic sources (24.8%). PAHs were mainly concentrated in the industrialized and urbanized regions and the harbor, and were transported by atmospheric deposition to the marine matrix. The mass inventory (1.57–2.62t) and probability risk showed sediments here served as an important reservoir but low PAH risk. Different from oil and natural gas in developed regions, coal combustion has always been a significant energy consumption pattern in this developing region for the past 30years (56±5%).
Show more [+] Less [-]Effect of heavy metals on the carbon and nitrogen ratio in Avicennia marina from polluted and unpolluted regions Full text
2015
Yadav, Ajay | Ram, Anirudh | Majithiya, Divya | Salvi, Shailesh | Sonavane, Swati | Kamble, Archana | Ghadigaonkar, Suman | Jaiswar, Jiyalal Ram M. | Gajbhiye, S.N.
The accumulation of heavy metals and its impact on the C/N ratio of Avicennia marina of the Patalganga and Amba estuaries were studied. Vadinar was selected as a relatively uncontaminated location for comparison. Cd was accumulated in leaves of the Patalganga and Amba estuarine mangroves; however, at Vadinar it was accumulated and arrested only in roots and stems. Negative correlation of Cr, Cd, Pb and Zn with C in the mangroves suggested that their accumulation may lead to lowered C content in the mangroves. The average C/N ratios in mangroves of the inner Patalganga estuary, Patalganga mouth, and Amba estuary were found to be 80.1±7.3, 105.8±12.5 and 52.4±3.4 respectively, whereas at Vadinar it was well within the expected range (26.4±2.8). The results of the present study suggest: (i) metal accumulation, leading to less carbon content in plants; (ii) heavy metal enrichment in the root zone sediment, affecting the uptake of nitrogen by plants and resulting in altered C/N ratio.
Show more [+] Less [-]Abundance, size and polymer composition of marine microplastics ≥10μm in the Atlantic Ocean and their modelled vertical distribution Full text
2015
Enders, Kristina | Lenz, Robin | Stedmon, Colin A. | Nielsen, Torkel G.
We studied abundance, size and polymer type of microplastic down to 10μm along a transect from the European Coast to the North Atlantic Subtropical Gyre (NASG) using an underway intake filtration technique and Raman micro-spectrometry. Concentrations ranged from 13 to 501itemsm−3. Highest concentrations were observed at the European coast, decreasing towards mid-Atlantic waters but elevated in the western NASG. We observed highest numbers among particles in the 10–20μm size fraction, whereas the total volume was highest in the 50–80μm range. Based on a numerical model size-dependent depth profiles of polyethylene microspheres in a range from 10–1000μm were calculated and show a strong dispersal throughout the surface mixed layer for sizes smaller than 200μm. From model and field study results we conclude that small microplastic is ubiquitously distributed over the ocean surface layer and has a lower residence time than larger plastic debris in this compartment.
Show more [+] Less [-]The assessment of the spatial and seasonal variability of chromophoric dissolved organic matter in the Southern Yellow Sea and the East China Sea Full text
2015
Su, Rongguo | Bai, Ying | Zhang, Chuansong | Shi, Xiaoyong
Samples of chromophoric dissolved organic matter (CDOM) from the Southern Yellow Sea (SYS) and the East China Sea (ECS) were evaluated by fluorescent Excitation Emission Matrix (EEM) combined with Parallel Factorial Analysis (PARAFAC). Three terrestrial humic-like components (C1, C2 and C3) and one autochthonous protein-like component (C4) were identified. As for seasonal variations, CDOM displayed the following order on the whole: summer>spring>autumn. The C1, C2 and C3 components were mainly dominated by terrestrial inputs and their spatial distributions and temporal variations also can be influenced by primary productivity of phytoplankton, microbial activities and photobleaching. C4 was produced by phytoplankton and microorganisms and consumed by marine bacteria, and besides its distribution was attributed to the influence of riverine inputs. Terrestrial inputs were the dominant sources of CDOM in the SYS and ECS.
Show more [+] Less [-]Sources, concentrations and risk factors of organochlorine pesticides in soil, water and sediment in the Yellow River estuary Full text
2015
Li, Jing | Li, Fadong | Liu, Qiang
The environmental occurrence, sources and risk factors of organochlorine pesticides (HCHs and DDTs) and their isomers or metabolites were studied using comprehensive surveys (including soil, surface water, groundwater and sediment sampling) conducted in the Yellow River Delta (YRD). HCHs and DDTs were all detected in multi environmental media. Compared with reported organochlorine pesticide values in China and abroad and with related environmental quality standards, the concentrations of HCHs and DDTs were generally at low levels in the YRD. Composition of OCPs (DDT metabolites and HCH isomers) showed that DDTs in the multiple environments of the YRD not only came from residues of dicofol but also from atmospheric deposition, while HCH pollution results from the historical usage of a mixture of technical HCH and lindane. Furthermore, the sum of Excess Lifetime Cancer Risk (∑ELCR) exposure to HCHs exceeded the generally acceptable risk level of 1.0E-06 recommended by the USEPA for carcinogenic chemicals.
Show more [+] Less [-]Intersex related gene expression profiles in clams Scrobicularia plana: Molecular markers and environmental application Full text
2015
Ciocan, Corina M. | Cubero-Leon, Elena | Langston, William J. | Pope, Nick | Cornelius, Keith | Hill, E.M. | Alvarez-Munoz, Diana | Indiveri, Paolo | Lerebours, Adelaide | Minier, Christophe | Rotchell, Jeanette M.
Intersex, the appearance of female characteristics in male gonads, has been identified in several aquatic species. It is a widespread phenomenon in populations of the bivalve, Scrobicularia plana, from the southwest coast of the U.K. Genes previously identified as differentially expressed (ferritin, testicular haploid expressed gene, THEG, proliferating cell nuclear antigen, PCNA; receptor activated protein kinase C, RACK; cytochrome B, CYB; and cytochrome c oxidase 1, COX1) in intersex clams relative to normal male clams, were selected for characterisation and an environmental survey of the Channel region. Transcripts were significantly differentially expressed at sites with varying intersex incidence and contaminant burdens. Significant correlations between specific gene expressions, key contaminants and sampling locations have been identified, though no single gene was associated with intersex incidence. The results highlight the difficulty in understanding the intersex phenomenon in molluscs where there is still a lack of knowledge on the control of normal reproduction.
Show more [+] Less [-]Marine governance in the English Channel (La Manche): Linking science and management Full text
2015
Glegg, G. | Jefferson, R. | Fletcher, S.
The English Channel is one of the world’s busiest sea areas with intense shipping and port activity juxtaposed with recreation, communications and important conservation areas. Opportunities for marine renewable energy vie with existing activities for space. The current governance of the English Channel is reviewed and found to lack integration between countries, sectors, legislation and scientific research. Recent developments within the EU’s marine management frameworks are significantly altering our approach to marine governance and this paper explores the implications of these new approaches to management of the English Channel. Existing mechanisms for cross-Channel science and potential benefits of an English Channel scale perspective are considered. In conclusion, current management practices are considered against the 12 Malawi Principles of the ecosystem approach resulting in proposals for enhancing governance of the region through science at the scale of the English Channel.
Show more [+] Less [-]Electrospun PS/PAN fibers with improved mechanical property for removal of oil from water Full text
2015
Li, Peng | Qiao, Ying | Zhao, Lili | Yao, Dahu | Sun, Haixiang | Hou, Yingfei | Li, Shuo | Li, Qi
A mechanically robust and high-capacity oil sorbent is prepared by electrospinning a blend of polystyrene (PS) and polyacrylonitrile (PAN). The morphology, oil sorption capacity and mechanical property of the fibers formed in different compositions are investigated in detail. It is shown that the oil sorption capacity is a result of both the chemical composition and the specific surface area which related to diameter size. The addition of PAN as a component in fibrous sorbents can significantly improve the mechanical properties of PS fibers. Moreover, the oil sorption capacity increases with decreasing fiber diameter. The results also show that the maximum sorption capacities of the PS/PAN sorbent for pump oil, peanut oil, diesel, and gasoline were 194.85, 131.70, 66.75, and 43.38gg−1, respectively. Additionally, the sorbent exhibits quick oil sorption speed as well as high buoyancy, which make it a promising candidate for use as an oil spill cleanup sorbent.
Show more [+] Less [-]A drifter for measuring water turbidity in rivers and coastal oceans Full text
2015
Marchant, Ross | Reading, Dean | Ridd, James | Campbell, Sean | Ridd, Peter
A disposable instrument for measuring water turbidity in rivers and coastal oceans is described. It transmits turbidity measurements and position data via a satellite uplink to a processing server. The primary purpose of the instrument is to help document changes in sediment runoff from river catchments in North Queensland, Australia. The ‘river drifter’ is released into a flooded river and drifts downstream to the ocean, measuring turbidity at regular intervals. Deployment in the Herbert River showed a downstream increase in turbidity, and thus suspended sediment concentration, while for the Johnstone River there was a rapid reduction in turbidity where the river entered the sea. Potential stranding along river banks is a limitation of the instrument. However, it has proved possible for drifters to routinely collect data along 80km of the Herbert River. One drifter deployed in the Fly River, Papua New Guinea, travelled almost 200km before stranding.
Show more [+] Less [-]Evaluation of beach cleanup effects using linear system analysis Full text
2015
Kataoka, Tomoya | Hinata, Hirofumi
We established a method for evaluating beach cleanup effects (BCEs) based on a linear system analysis, and investigated factors determining BCEs. Here we focus on two BCEs: decreasing the total mass of toxic metals that could leach into a beach from marine plastics and preventing the fragmentation of marine plastics on the beach. Both BCEs depend strongly on the average residence time of marine plastics on the beach (τr) and the period of temporal variability of the input flux of marine plastics (T). Cleanups on the beach where τr is longer than T are more effective than those where τr is shorter than T. In addition, both BCEs are the highest near the time when the remnants of plastics reach the local maximum (peak time). Therefore, it is crucial to understand the following three factors for effective cleanups: the average residence time, the plastic input period and the peak time.
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