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Coastal debris analysis in beaches of Chonburi Province, eastern of Thailand as implications for coastal conservation Full text
2017
Thushari, Gajahin Gamage Nadeeka | Chavanich, Suchana | Yakupitiyage, Amararatne
This study quantified coastal debris along 3 beaches (Angsila, Bangsaen, Samaesarn) in eastern coast of Thailand. Debris samples were collected from lower and upper strata of these beaches during wet and dry seasons. The results showed that Bangsaen had the highest average debris density (15.5m−2) followed by Samaesarn (8.10m−2), and Angsila (5.54m−2). Among the 12 debris categories, the most abundant debris type was plastics (>45% of the total debris) in all beach locations. Coastal debris distribution was related to economic activities in the vicinity. Fishery and shell-fish aquaculture activities were primary sources of debris in Angsila while tourism activities were main sources in Bangsaen and Samaesarn. Site-specific pollution control mechanisms (environmental awareness, reuse and recycling) are recommended to reduce public littering. Management actions in Angsila should focus on fishery and shell-fish culture practices, while Bangsaen and Samaesarn should be directed toward leisure activities promoting waste management.
Show more [+] Less [-]Oil spill off the coast of Guimaras Island, Philippines: Distributions and changes of polycyclic aromatic hydrocarbons in shellfish Full text
2017
The sinking of the Solar 1 tanker caused serious heavy oil pollution around Guimaras Island, Philippines. In the present study, variations of parent polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs (alkPAHs) in some shellfish were investigated around Guimaras Island and other small islands from 3months to 5years after the spill. The total PAHs and alkPAHs in shellfish were detected in high concentrations at 448 and 33,666ng/g dry weight, respectively, in November 2006. The concentrations of alkPAHs gradually decreased, while the parent PAHs in shellfish degraded more slowly than the alkPAHs, which was likely due to the persistent characteristics of PAHs. The risks based on European Union regulations were insignificant in 2008, but total PAHs in shellfish were still over 8 times higher at the investigated sites in November 2011 than that before the oil spill.
Show more [+] Less [-]Management and environmental risk study of the physicochemical parameters of ballast water Full text
2017
Shipping is a vital industry for the global economy. Stability of ships, provided by ballast water, is a crucial factor for cargo loading and unloading processes. Ballast water treatment has practical significance in terms of environmental issues, ecosystem, and human health, because ships discharge this water into the environment before loading their cargos. This study reviews the common methods for ballast water management – exchange, heating, filtration, ultrasonic treatment, ultraviolet irradiation, chemicals, and gas supersaturation – to select the best one. This study compares water temperature, salinity, dissolved oxygen, polycyclic aromatic hydrocarbons (PAHs), and heavy metals (Co, Cr, Ni, Pb) for ballast tanks of selected ships with the recipient port environment in the Persian Gulf as a case study. The exchange of ballast water in the ocean and/or its treatment on board to prevent inadvertent effects on the environment's physicochemical conditions is related to vessel characteristics, legislation, and the environmental condition. Ecological risk study showed that the salt content in ballast water is close to that of seawater, but the values of Cr (2.1mg/l) and Ni (0.029mg/l) in ballast water are higher than those in seawater (1 and 0.004mg/l, respectively).
Show more [+] Less [-]Displacement effects of heavy human use on coral reef predators within the Molokini Marine Life Conservation District Full text
2017
The impact of marine ecotourism on reef predators is poorly understood and there is growing concern that overcrowding in Marine Protected Areas (MPAs) may disturb the species that these areas were established to protect. To improve our understanding of this issue, we used acoustic telemetry to examine the relationship between human activity at the Molokini Marine Life Conservation District (MLCD) and the habitat use of five reef-associated predators (Caranx melampygus, Caranx ignobilis, Triaenodon obesus, Carcharhinus amblyrhynchos, and Aprion virscens). During peak hours of human use, there was a negative relationship (R2=0.77, P<0.001) between the presence of bluefin trevally (Caranx melampygus) and vessels in subzone A. No other species showed strong evidence of this relationship. However, our results suggest that during this time, the natural ecosystem function that the reserve was established to protect may be compromised and overcrowding should be considered when managing MPAs.
Show more [+] Less [-]Spatial variability of E. coli in an urban salt-wedge estuary Full text
2017
Jovanović, Dušan | Coleman, Rhys | Deletic, A. (Ana) | McCarthy, David
This study investigated the spatial variability of a common faecal indicator organism, Escherichia coli, in an urban salt-wedge estuary in Melbourne, Australia. Data were collected through comprehensive depth profiling in the water column at four sites and included measurements of temperature, salinity, pH, dissolved oxygen, turbidity, and E. coli concentrations. Vertical variability of E. coli was closely related to the salt-wedge dynamics; in the presence of a salt-wedge, there was a significant decrease in E. coli concentrations with depth. Transverse variability was low and was most likely dwarfed by the analytical uncertainties of E. coli measurements. Longitudinal variability was also low, potentially reflecting minimal die-off, settling, and additional inputs entering along the estuary. These results were supported by a simple mixing model that predicted E. coli concentrations based on salinity measurements. Additionally, an assessment of a sentinel monitoring station suggested routine monitoring locations may produce conservative estimates of E. coli concentrations in stratified estuaries.
Show more [+] Less [-]Effects of hypoxia in the gills of the Manila clam Ruditapes philippinarum using NMR-based metabolomics Full text
2017
Zhang, Ying | Wu, Huifeng | Wei, Lei | Xie, Zeping | Guan, Bo
Coastal hypoxia affects the survival, behavior, and reproduction of individual local marine organisms, and the abundance, biomass, and biodiversity of coastal ecosystems. In this study, we investigated the chronic effects of hypoxia on the metabolomics in the gills of Ruditapes (R.) philippinarum. The results indicated significant alterations in the metabolite profiles in the gills of the hypoxia-treated clams, in comparison with those maintained under normoxia. The levels of betaine, taurine, glycine, isoleucine, and alanine were significantly reduced, suggesting a disturbance of osmotic balance associated with hypoxia. Meanwhile, metabolites involved in energy metabolism, such as alanine and succinate, were also affected. Dramatic histopathological changes were observed in the gills and hepatopancreases of R. philippinarum grown in hypoxic waters, demonstrating tissue damages apparently caused by long-term exposure to hypoxia. Our findings suggest that hypoxia significantly affects the physiology of R. philippinarum, even at a sub-lethal level, and impedes health of the clams.
Show more [+] Less [-]Effects of metal contamination on the gene expression profile of two benthic species: Cerastoderma edule and Ruditapes philippinarum Full text
2017
This study aimed to identify new biomarkers for metal exposure in two bivalve species. Suppressive Subtractive Hybridization (SSH) was employed to evaluate the transcriptomic response of Cerastoderma edule and Ruditapes philippinarum to metal pollution. Protein synthesis and catalytic activity were the most affected metabolic processes in C. edule and R. philippinarum, respectively. Also, different genes responded to the effect of contamination in each species. The different response observed in both species reinforces the importance of including more than one bioindicator species in risk assessment studies. These results provide the basis for new studies, which are necessary for further validation of the use of the identified genes as molecular biomarkers for metal exposure.
Show more [+] Less [-]Floating marine litter as a raft for drifting voyages for Planes minutus (Crustacea: Decapoda: Grapsidae) and Liocarcinus navigator (Crustacea: Decapoda: Polybiidae) Full text
2017
Tutman, P. | Kapiris, K. | Kirinčić, M. | Pallaoro, A.
The Columbus crab Planes minutus and Arch-fronted swimming crab Liocarcinus navigator, within their distribution ranges in the Mediterranean, were found rafted on plastic macro-litter floating on the open south Adriatic. While P. minutus was recorded from inanimate flotsam outside of the Mediterranean, L. navigator is herein reported for the first time on floating marine litter. The role of floating litter as habitat or as a dispersal agent for marine invertebrates has received quite attention however, records of decapod crabs drifting on litter has been relatively sparse. Our results suggests that vast quantities of floating debris, comprised primarily of non-biodegradable plastic polymers, probably will augment natural floating substrates in the marine environment, potentially facilitating the spread of invasive species. The dispersion of rafting crabs through floating debris should be investigated given the high potential ecological risk of invasion by exotic species due to the increase in waste production (ecological risk assessment).
Show more [+] Less [-]Environmental consequences of the flooding of the Bay Park Sewage Treatment Plant during Superstorm Sandy Full text
2017
Swanson, R Lawrence | Wilson, Robert | Brownawell, Bruce | Willig, Kaitlin
Failure of the Bay Park Sewage Treatment Plant (STP) during Superstorm Sandy led to adverse effects in the waters of Hempstead Bay, Long Island, NY. These appear to be related to large discharges of partially treated sewage through its primary and auxiliary outfalls. Modeled dilution discharges indicate that sewage infiltrated the bay, remaining up to 10days. Water column impacts included salinity and dissolved oxygen declines, and biological oxygen demand and nitrogen concentration increases. While the STP does not appear to have released fecal coliform, there were elevated levels of enterococci within the bay for a considerable period following the storm, probably from multiple sources.The STP's reduced functioning and associated environmental impacts, even with resilience upgrades, are not conducive to removing the bay from the list of Impaired Water Bodies. The results reinforce the need to transfer the discharge from the existing outfall to the ocean.
Show more [+] Less [-]Determination of hydrocarbons transported by urban runoff in sediments of São Gonçalo Channel (Pelotas – RS, Brazil) Full text
2017
Sanches Filho, Pedro J. | Böhm, Emerson M. | Böhm, Giani M.B. | Montenegro, Gissele O. | Silveira, Lucas A. | Betemps, Glauco R.
A high concentration of hydrocarbons in the environment is indicative of pollution. To evaluate the effect of hydrocarbons transported by urban runoff, the present study analyzed total petroleum hydrocarbons (TPHs), aliphatic hydrocarbons (AHs), unresolved complex mixture (UCM), and n-alkanes of the sediments of the canal that cross the urban area of Pelotas, Rio Grande do Sul, Brazil. The carbon preference index (CPI), terrigenous/aquatic ratio (TAR), and pristane/phytane ratio were determined. The TPH content ranged from 177,043.7μg·kg−1±13.4% to 5,892,667.0μg·kg−1±5.9%. The total aliphatic content ranged from 116,268.8μg·kg−1±11.1% to 2,393,592.6μg·kg−1±7.7%, indicating chronic contamination of n-alkanes petrogenic and biogenic sources. The levels of hydrocarbons (TPH, AHs, and n-alkanes) were considered relatively high, confirming the effect of urban runoff on the drainage system of cities and their consequent effect on the estuarine region of Patos Lagoon and other water resources.
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