Correction to: Survey of coastal inland pollution sources and their influence on seawater quality in Doam bay, Korea.

The original version of this article unfortunately contained an error in the affiliation section.

Survey of coastal inland pollution sources and their influence on seawater quality in Doam bay, Korea.

Inland pollution sources of Doam bay were investigated from August to October in 2013. A total of 210 sources including rivers, streams, domestic, agricultural and industrial discharge points were identified along the coast, including 32 sources that had outflow. Agricultural sources were the largest inland pollution sources (139, 66.2%). Fecal coliform concentrations were measured. These data were combined with water discharge data to determine daily loads of pollutants discharged from each source into the bay. Fecal coliform concentrations were the highest in domestic discharges. However, they only had slight influence because their discharge volume was small. The most significant pollution source was Tamjin River (St.85) due to large amount of discharge volume. The influence of St.85 reached almost half of Doam bay. Fecal coliform levels of streams increased after rainfall, but decreased overtime. Domestic pollution sources were not affected upon rain event.

Disinfection of ballast water with iron activated persulfate.

The treatment of ballast water carried onboard ships is critical to reduce the spread of nonindigenous aquatic organisms that potentially include noxious and harmful taxa. We tested the efficacy of persulfate (peroxydisulfate, S2O8(2-), PS) activated with zerovalent iron (Fe(0)) as a chemical biocide against two taxa of marine phytoplankton grown in bench-scale, batch cultures: the diatom, Pseudonitzshia delicatissima and the green alga, Dunaliella tertiolecta . After testing a range of PS concentrations (0-4 mM activated PS) and exposure times (1-7 days), we determined that a dosage of 4 mM of activated PS was required to inactivate cells from both species, as indicated by reduced or halted growth and a reduction in photosynthetic performance. Longer exposure times were required to fully inactivate D. tertiolecta (7 days) compared to P. delicatissima (5 days). Under these conditions, no recovery was observed upon placing cells from the exposed cultures into fresh media lacking biocide. The results demonstrate that activated PS is an effective chemical biocide against species of marine phytoplankton. The lack of harmful byproducts produced during application makes PS an attractive alternative to other biocides currently in use for ballast water treatments and merits further testing at a larger scale.

Formic acid as an alternative reducing agent for the catalytic nitrate reduction in aqueous media.

Formic acid was used for the nitrate reduction as a reductant in the presence of Pd:Cu/gamma-alumina catalysts. The surface characteristics of the bimetallic catalyst synthesized by wet impregnation were investigated by SEM, TEM-EDS. The metals were not distributed homogeneously on the surface of catalyst, although the total contents of both metals in particles agreed well with the theoretical values. Formic acid decomposition on the catalyst surface, its influence on solution pH and nitrate removal efficacy was investigated. The best removal of nitrate (50 ppm) was obtained under the condition of 0.75 g/L catalyst with Pd:Cu ratio (4:1) and two fold excess of formic acid. Formic acid decay patterns resembled those of nitrate removal, showing a linear relationship between k(f) (formic acid decay) and k (nitrate removal). Negligible amount of ammonia was detected, and no nitrite was detected, possibly due to buffering effect of bicarbonate that is in situ produced by the decomposition of formic acid, and due to the sustained release of H2 gas.

Wandonia haliotis gen. nov., sp. nov., a marine bacterium of the family Cryomorphaceae, phylum Bacteroidetes.

A novel, strictly aerobic, Gram-stain-negative, yellow-orange-pigmented, rod-shaped bacterium was isolated from abalone (Haliotis discus) under aquaculture in seawater off the Wando coast, Southern Korea, and subjected to a polyphasic taxonomic study. Cells of strain Haldis-1(T) were catalase- and oxidase-positive rods with flexirubin pigments. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Haldis-1(T) formed a distinct lineage within the family Cryomorphaceae and could be distinguished from the related genera Lishizhenia and Fluviicola. Strain Haldis-1(T) shared 16S rRNA gene sequence similarities of 92.5 and 92.4 % with Lishizhenia caseinilytica UST040201-001(T) and Fluviicola taffensis RW262(T), respectively. The DNA G+C content was 38.1 mol% and the major respiratory quinone was MK-7. The predominant cellular fatty acids were iso-C(15 : 0) (38.6 %), C(15 : 0) 2-OH (20.3 %) and C(15 : 0) (10.7 %). Growth was observed at 25-42 degrees C (optimum 30-37 degrees C) and at pH 6.5-9.5 (optimum pH 6.5-8.0). On the basis of polyphasic analysis of phenotypic, genotypic and phylogenetic data, strain Haldis-1(T) represents a novel genus and species within the family Cryomorphaceae in the phylum Bacteroidetes, for which the name Wandonia haliotis gen. nov., sp. nov. is proposed. The type strain is Haldis-1(T) (=KCTC 22610(T) =NBRC 105642(T)).

Fe(0) nanoparticles for nitrate reduction: stability, reactivity, and transformation.

The pyrophoric character of zerovalent iron nanoparticles and cumbersome handling of this material has been a drawback in practical applications, despite the expectation of an enhanced reactivity. We have been interested in how the iron nanoparticles can gain stability in air without significantly sacrificing reactivity. The freshly synthesized iron nanoparticles ignited spontaneously upon exposure to air. However, when exposed slowly to air, an approximately 5 nm coating of iron oxide was formed on the surface of particles. The oxide shell did not thicken for at least two months, indicating no sign of further corrosion of iron particles. The reactivity studies on nitrate reduction showed that the freshly synthesized iron reacted at the fastest rate. After formation of the oxide shell the rate constants decreased by ca. 50% of that of fresh iron, but were still higher than that of commercial grade micro- or milli-sized iron powder. Nitrate (50 ppm/350 mL) can be recharged 6 times into a bottle containing 0.5 g of iron nanoparticles. The reduction rate of the second cycle was the fastest among the six cycles, which can be attributed to the increase of surface area and the fresh iron surfaces that were bared by the dissolution of oxidized iron species on the surface. The oxidized iron was transformed to crystalline magnetite (Fe3O4) in solution.