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Kinetic analysis of simultaneous denitrification and biomineralization of novel Acinetobacter sp. CN86 Texto completo
2016
Su, Jun-feng | Shi, Jing-xin | Huang, Ting-lin | Ma, Fang
A novel aerobic denitrification and biomineralization strain CN86 was isolated from the Qu Jiang artificial lake. Based on phylogenetic characteristics, the isolated strain was identified as Acinetobacter species. Strain CN86 was confirmed to have the ability to perform simultaneous denitrification and biomineralization. Exponential decay equation was used for the matching of kinetic processes on denitrification and biomineralization. A highest nitrate removal rate was achieved at the pH7.0, organic concentration of 1.5g/L and temperature of 30°C. An optimal hardness removal rate was obtained at the pH9.0, organic concentration of 2.0g/L and temperature of 30°C. Strain CN86 is a suitable candidate for the simultaneous removal of nitrate and hardness in groundwater treatment.
Mostrar más [+] Menos [-]Chemical composition of floating and sunken in-situ burn residues from the Deepwater Horizon oil spill Texto completo
2016
Stout, Scott A. | Payne, James R.
In-situ burning during the Deepwater Horizon oil spill generated tens of thousands of barrels of in-situ burn (ISB) residues in the northern Gulf of Mexico (GoM), most or all of which eventually sank to the seafloor. Chemical analyses showed that floating and sunken (~1400m deep) ISB residues (1) exhibited distinct n-alkanes and UCM profiles inconsistent with vapor-pressure driven evaporation, (2) were relatively enriched in pyrogenic PAHs, particularly less stable (mostly) linear PAH isomers formed during burning, and (3) had lost petroleum biomarkers, relative to their volatility. PAH concentrations in ISB residues indicate that between 26,800 and 37,800kg of total PAHs (TPAH51) and 2880 and 4060kg of 16 Priority Pollutant PAHs were potentially deposited on the seafloor in discrete ISB residue particles. Despite this additional benthic impact, ISB reduced the total mass loadings of PAH from the burned oil to the GoM by 89% (ignoring any re-deposition from atmospheric emissions).
Mostrar más [+] Menos [-]The influence of wastewater discharge on water quality in Hawai'i: A comparative study for Lahaina and Kihei, Maui Texto completo
2016
Miller-Pierce, Mailea R. | Rhoads, Neil A.
In Maui, Hawai'i, wastewater reclamation facilities (WWRFs) dispose of partially treated effluent into injection wells connected to the nearshore environment. Hawai'i State Department of Health data from 2004–2015 were assessed for qualitative trends in nutrient, turbidity, and Chlorophyll a water quality (WQ) impairments for fourteen marine sites on Maui Island. We introduce a novel method, the Qualitative Impact Percentage (QIP), to facilitate a qualitative comparison of disparate factors contributing to WQ impairment. Sites near the Lahaina WWRF in West Maui, which was found in violation of the Clean Water Act in 2014, had fewer exceedances and lower geometric means compared to sites near the Kihei WWRF. Our results suggest that WQ impairments may be a greater concern in Kihei than previously acknowledged. This paper attempts to raise the awareness of policymakers and the public and to encourage further research assessing the effects of the Kihei WWRF on the marine environment.
Mostrar más [+] Menos [-]Heavy metals in river and coast sediments of the Jakarta Bay region (Indonesia) — Geogenic versus anthropogenic sources Texto completo
2016
Sindern, Sven | Tremöhlen, Martin | Dsikowitzky, Larissa | Gronen, Lars | Schwarzbauer, Jan | Siregar, Tuti Hartati | Ariyani, Farida | Irianto, Hari Eko
Sediment geochemistry of the Jakarta region, a densely populated tropical coast, is studied — with particular focus on rivers discharging to Jakarta Bay. Weathering volcanics in the river catchment area control the composition of major elements, As, Cr and in part Cu. In contrast, Zn, Ni, Pb and partly Cu are affected by anthropogenic sources, mainly in central Jakarta City. The data reflect a high variability of local emission sources, among which metal processing industries, fertilizers or untreated animal waste may be important. In particular, the role of street dusts is emphasized. Locally, heavy metals reach levels considered to have adverse biological effects. River discharge leads to anthropogenic enrichment of heavy metals in the coastal sediments. Element data also show geogenic effects on the composition of the coastal sediments, such as mixing of detrital silicates with biogenic carbonates as well as suspended particulate matter from the ocean.
Mostrar más [+] Menos [-]Seasonal distribution of metals in vertical and horizontal profiles of sheltered and exposed beaches on Polish coast Texto completo
2016
Bigus, Katarzyna | Astel, Aleksander | Niedzielski, Przemysław
The distribution of alkali and heavy metals in coastal sediments of three Polish beaches was assessed. In all locations there are sandy beaches of different characteristics according to the anthropogenic impact and degree of sheltering. Core sediments collected in Czołpino and Ustka were characterized by the highest concentration of Cd, Ag, Ba, and Al, Cu, Cr, Bi, Na, respectively. Among the alkaline metals core sediments were the most abundant with Ca, Bi, Mg and Na, presenting almost stable decreasing order in all beaches. The majority of dredge material collected can be classified as light or trace contaminated by Cr, Cu, Zn, Cd and Hg. An abundance of mineralogical components in core sediments in Ustka increases in Summer and Autumn, while in Puck is stable throughout the year. The content of studied metals in core sediments collected in three Polish beaches changes both in the vertical and horizontal profiles of the beach.
Mostrar más [+] Menos [-]Predation mechanisms of Rapana venosa (Gastropoda: Muricidae) in different biotopes along the Black Sea coast Texto completo
2016
Kosyan, Alisa
Mechanisms of feeding by the invasive gastropod Rapana venosa from different biotopes of 11 sites along the Black Sea coast are discussed. Two methods – edge-drilling and suffocation – are used, but the prevailing method in a particular biotope depends on the type of bivalve prey. Drill signs were present on almost all shells of Chamelea gallina, captured by rapa whelks in field conditions, while in a field experiment, only 11% of all empty Mytilus galloprovincialis had drilling signatures. The degree of radula abrasion was also dependent on the available bivalves: it was the highest in biotopes with C. gallina and juvenile mussels, and the lowest in biotopes with large mussels. Intermediate degrees of abrasion were observed in biotopes with mixed prey: C. gallina and Anadara kagoshimensis, C. gallina and mussels, or small and large mussels. Since we observed only initial signs of drilling, simultaneous application of boring and suffocation could take place.
Mostrar más [+] Menos [-]Assessing the progress in depolluting the Mediterranean Sea Texto completo
2016
Spiteri, Claudette | Roddier-Quefelec, Cécile | Giraud, Jean-Pierre | Hema, Tatiana
The depollution of the Mediterranean Sea by 2020 is the overarching goal of Horizon 2020 Initiative (H2020). The first phase (2007–2013) tackled the main land-based pollution sources; municipal waste, urban wastewater and industrial emissions. As part of the H2020 roadmap implementation, the ENPI-SEIS project focused on the first H2020 review mechanism that included a) establishing a process for regular environmental reporting in the European Neighbourhood Policy South countries, and b) generating the knowledge necessary to assess the progress in depolluting the Mediterranean Sea. This paper reviews the process in line with the “Shared Environmental Information System” principles and its three pillars (content, cooperation, infrastructure). The main outcomes of the thematic assessment, based on a set of regional H2020 indicators, are also presented. This assessment highlights the major drivers and their implications on marine protection. It also identifies areas that require further attention in the next phase of H2020 (2014–2020).
Mostrar más [+] Menos [-]Regional variability in bed-sediment concentrations of wastewater compounds, hormones and PAHs for portions of coastal New York and New Jersey impacted by hurricane Sandy Texto completo
2016
Phillips, Patrick J. | Gibson, Catherine A. | Fisher, Shawn C. | Fisher, Irene J. | Reilly, Timothy J. | Smalling, Kelly L. | Romanok, Kristin M. | Foreman, William T. | ReVello, Rhiannon C. | Focazio, Michael J. | Jones, Daniel K.
Bed sediment samples from 79 coastal New York and New Jersey, USA sites were analyzed for 75 compounds including wastewater associated contaminants, PAHs, and other organic compounds to assess the post-Hurricane Sandy distribution of organic contaminants among six regions. These results provide the first assessment of wastewater compounds, hormones, and PAHs in bed sediment for this region. Concentrations of most wastewater contaminants and PAHs were highest in the most developed region (Upper Harbor/Newark Bay, UHNB) and reflected the wastewater inputs to this area. Although the lack of pre-Hurricane Sandy data for most of these compounds make it impossible to assess the effect of the storm on wastewater contaminant concentrations, PAH concentrations in the UHNB region reflect pre-Hurricane Sandy conditions in this region. Lower hormone concentrations than predicted by the total organic carbon relation occurred in UHNB samples, suggesting that hormones are being degraded in the UHNB region.
Mostrar más [+] Menos [-]Perfluoroalkylated substances (PFASs) and legacy persistent organic pollutants (POPs) in halibut and shrimp from coastal areas in the far north of Norway: Small survey of important dietary foodstuffs for coastal communities Texto completo
2016
Carlsson, Pernilla | Crosse, John D. | Halsall, Crispin | Evenset, Anita | Heimstad, Eldbjørg S. | Harju, Mikael
Halibut (Hippoglossus hippoglossus) and shrimps (Pandalus borealis) are regular foodstuffs for communities in northern Norway and important species for the coastal fishing industry. This is the first study to present a comprehensive overview of the contaminant status of these species, with emphasis on unregulated perfluoroalkylated substances (PFAS). The contaminant concentrations were low and within tolerable levels for human dietary exposure. Median Σpolychlorinated biphenyls (PCB) were 4.9 and 2.5ng/g ww for halibut and unpeeled shrimps, respectively. Concentrations of perfluorooctane sulfonate (PFOS) – the most abundant PFASs – were 0.9 and 2.7ng/g ww in halibut and shrimp, respectively. The halibut fillets were dominated by PCBs, which contributed to 50% of the total POPs load, followed by ΣDDTs; 26% and PFASs (18%), whereas shrimps were dominated by PFASs (74%). ΣPBDEs (polybrominated diphenyl ethers) contributed to 1–4% of the total POP load. Local sources are not contributing significantly to the contaminant burden in these species.
Mostrar más [+] Menos [-]Levels of genetic diversity and taxonomic status of Epinephelus species in United Arab Emirates fish markets Texto completo
2016
Ketchum, Remi N. | Dieng, Mame M. | Vaughan, Grace O. | Burt, John A. | Idaghdour, Youssef
Understanding the patterns of genetic diversity of fish species is essential for marine conservation and management. This is particularly important in the Arabian Gulf where marine life is subject to extreme environmental conditions that could impact genetic diversity. Here we assess genetic diversity of the most commercially important fish in the United Arab Emirates; groupers (Epinephelus spp.). Sequencing of 973bp mitochondrial DNA from 140 tissue samples collected in four main fish markets revealed 58 haplotypes clustered within three groups. Data analysis revealed the presence of three distinct Epinephelus species being marketed as one species (hammour): Epinephelus coioides, Epinephelus areolatus and Epinephelus bleekeri. We report species-specific genetic markers and demonstrate that all three species exhibit relatively low levels of genetic variation, reflecting the effect of overfishing and environmental pressures. In light of the genetic evidence presented here, conservation and management of groupers in the UAE warrant the implementation of species-specific measures.
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