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Impact of industrial pollution on recent dinoflagellate cysts in Izmir Bay (Eastern Aegean) Texto completo
2015
Aydın, Hilâl | Yürür, Emine Erdem | Uzar, Serdar | Küçüksezgin, Filiz
The spatial distribution of dinoflagellate cysts was studied to understand the impact of industrial pollution on the surface sediment of Izmir Bay, Turkey. Forty two dinoflagellate cyst morphotypes belonging to 12 genera were identified and qualified at 12 sampling points. The cyst of Gymnodinium nolleri dominated the bay and had the highest abundance in most of the stations, following Spiniferites bulloideus and Lingulodinium machaerophorum. The highest cyst concentration was recorded in the inner part of the bay. Cyst concentration ranged between 384 and 9944cystg−1 dry weight of sediment in the sampling area. Sediment metal concentrations were determined. Heavy metal levels in Izmir Inner Bay were higher than the Middle and Outer Bay. L. machaerophorum, Dubridinium caperatum and Polykrikos kofoidii showed significant positive correlation with some metals (Cd, Pb, Cu, Zn) and organic carbon content. However, there was no significant correlation between dinoflagellate cyst abundance and sediment type.
Mostrar más [+] Menos [-]Trophic implications and faunal resilience following one-off and successive disturbances to an Amphibolis griffithii seagrass system Texto completo
2015
Gartner, Adam | Lavery, Paul S. | Lonzano-Montes, Hector
Disturbances in seagrass systems often lead to considerable loss of seagrass fauna. We examined the capacity for seagrass fauna, across multiple trophic levels, to recover from disturbances, using empirical and modelling techniques. Model outputs, using Ecosim with Ecopath (EwE), were consistent with the results of field investigations, highlighting the models robustness. Modelled outcomes suggest second and third order consumers are likely to be negatively effected by disturbances in the seagrass canopy. Particularly piscivores, which once disturbed, appear unlikely to recover following severe declines in primary productivity. EwE also revealed the complex interaction between the duration and intensity of disturbances on seagrass fauna, which may differentially affect higher order consumers. Further, modelling predicted a variable capacity of higher order consumers to recover from successive disturbances, suggesting taxa with comparatively fast reproductive cycles and short generation terms would be more resilient than taxa with comparatively long generation terms and slow reproductive cycles.
Mostrar más [+] Menos [-]Assessment of oil slick hazard and risk at vulnerable coastal sites Texto completo
2015
Melaku Canu, Donata | Solidoro, Cosimo | Bandelj, Vinko | Quattrocchi, Giovanni | Sorgente, Roberto | Olita, Antonio | Fazioli, Leopoldo | Cucco, Andrea
This work gives an assessment of the hazard faced by Sicily coasts regarding potential offshore surface oil spill events and provides a risk assessment for Sites of Community Importance (SCI) and Special Protection Areas (SPA). A lagrangian module, coupled with a high resolution finite element three dimensional hydrodynamic model, was used to track the ensemble of a large number of surface trajectories followed by particles released over 6 selected areas located inside the Sicily Channel. The analysis was carried out under multiple scenarios of meteorological conditions. Oil evaporation, oil weathering, and shore stranding are also considered. Seasonal hazard maps for different stranding times and seasonal risk maps were then produced for the whole Sicilian coastline. The results highlight that depending on the meteo-marine conditions, particles can reach different areas of the Sicily coast, including its northern side, and illustrate how impacts can be greatly reduced through prompt implementation of mitigation strategies.
Mostrar más [+] Menos [-]The mussel caging approach in assessing biological effects of wastewater treatment plant discharges in the Gulf of Finland (Baltic Sea) Texto completo
2015
Turja, Raisa | Lehtonen, Kari K. | Meierjohann, Axel | Brozinski, Jenny-Maria | Vahtera, Emil | Soirinsuo, Anna | Sokolov, Alexander | Snoeijs, Pauline | Budzinski, Hélène | Devier, Marie-Hélène | Peluhet, Laurent | Pääkkönen, Jari-Pekka | Viitasalo, Markku | Kronberg, Leif
Biological effects of wastewater treatment plant (WWTP) effluents were investigated in Baltic mussels (Mytilus trossulus) caged for one month 800m and 1100m from the WWTP discharge site and at a reference site 4km away. Significant antioxidant, genotoxic and lysosomal responses were observed close to the point of the WWTP discharge. Passive samplers (POCIS) attached to the cages indicated markedly higher water concentrations of various pharmaceuticals at the two most impacted sites. Modeling the dispersal of a hypothetical passive tracer compound from the WWTP discharge site revealed differing frequencies and timing of the exposure periods at different caging sites. The study demonstrated for the first time the effectiveness of the mussel caging approach in combination with passive samplers and the application of passive tracer modeling to examine the true exposure patterns at point source sites such as WWTP pipe discharges in the Baltic Sea.
Mostrar más [+] Menos [-]A fish-based index for assessing the ecological status of Polish transitional and coastal waters Texto completo
2015
Smoliński, Szymon | Całkiewicz, Joanna
Fish assemblages are considered indicators of aquatic ecosystem quality. Based on how fish communities respond to anthropogenic pressures, we developed a multimetric fish index for evaluating the health of both coastal and transitional waters. Fish data were collected along the Polish coast in the years 2011, 2013 and 2014 using different types of gear. Redundancy analysis showed that the most important environmental factor affecting fish community was salinity. Responses to anthropogenic disturbances of 20 candidate metrics were tested by generalized linear models, taking into account salinity, sampling protocol and the proxy of human pressures described by the Baltic Sea Impact Index (BSII). Five selected metrics were combined in a Multimetric Index, which showed negative significant correlation with BSII. The index presented herein appeared to be a good tool for assessing the ecological state of highly impacted Polish transitional and coastal areas and complies with the Water Framework Directive requirements.
Mostrar más [+] Menos [-]Indoor and outdoor microbial aerosols at the holy mosque: A case study Texto completo
2015
Mashat, Bassam
The aim of this study was to evaluate bacterial and fungal aerosol concentrations at the holy mosque (Al-Masjid Al-Haram). Air samples were collected from different locations inside and outside the holy mosque, during the month of Ramadan-2011 (the fasting month), using a portable Air-port MD8 gelatin filter sampler. Trypticase soya agar and Capek's dox agar media were used to count bacteria and fungi, respectively. The mean concentrations of airborne bacteria and fungi ranged between 105–106 colony forming unit per cubic meter of air (CFU/m3) outside, and ∼102–105 CFU/m3 inside locations. The highest outside bacterial concentrations 106 CFU/m3 were found at the Al Umra, Al Fatah and eastern plazas, and the highest inside fungal concentrations ∼105 CFU/m3 were found at the courtyard, expansion of 1st floor, and roof. Significant differences (P < 0.05) were found between bacterial and fungal concentrations inside and outside sampling locations, higher concentrations shifted towards to outside locations. Significant differences were also found between the bacterial and fungal concentrations inside–unclosed and semi-closed (P < 0.05) with inside-closed locations. Gram-positive bacteria, Bacillus and Micrococcus, and fungi, Aspergillus niger were the dominant microbial aerosol genera. The obtained data is considered a step to make up the gap about airborne microbial contamination inside the holy mosque, and microbial air quality should be studied along over the year at the holy mosque in the future.
Mostrar más [+] Menos [-]Carriage of Clostridium perfringens by benthic crabs in a sewage-polluted estuary Texto completo
2015
La Sala, Luciano F. | Redondo, Leandro M. | Díaz Carrasco, Juan M. | Pereyra, Ana María | Farber, Marisa | Jost, Helen | Fernández-Miyakawa, Mariano E.
The Estuary of Bahía Blanca (EBB), Argentina, is an important wetland under intense sewage pollution. We investigated the occurrence of Clostridium perfringens (CP) in populations of two benthic crabs (Neohelice granulata and Cyrtograpsus angulatus) and in sediment from the EBB. CP was found in 49.1% of the crabs and all of the isolates were identified as type A. The alpha (cpa) and enterotoxin (cpe) encoding genes were identified. Genetic analyses identified 13 novel sequence types, and found no clustering among isolates, suggesting that CP is not part of the crabs’ commensal flora. CP carriage was 51 times more likely in crabs from the area nearest sewage outfalls compared with crabs from a reference site. Our in vitro experiments suggest that the carriage of CP in crabs is transient. The use of these benthic crabs as monitoring organisms of sewage pollution in coastal habitats is proposed.
Mostrar más [+] Menos [-]Intercomparison between NIOSH, IMPROVE_A, and EUSAAR_2 protocols: Finding an optimal thermal–optical protocol for Philippines OC/EC samples Texto completo
2015
Bautista, Angel T. | Pabroa, Preciosa Corazon B. | Santos, Flora L. | Quirit, Leni L. | Asis, Joannes Luke B. | Dy, Marie Alexandra K. | Martinez, Jason Patrick G.
Thermal–optical analysis is one of the most widely–recognized methods for measuring organic carbon (OC) and elemental carbon (EC) in atmospheric particulates. Up to date however, there is no standard protocol of analysis and different protocols give varying OC/EC apportionments. This study aims to find an optimal thermal–optical analysis protocol for Philippine OC/EC samples by comparing three widely–used protocols: NIOSH, IMPROVE_A and EUSAAR_2. Philippines is particularly interesting because it has one of the highest EC concentration and lowest OC/EC ratio in the region. In terms of total OC and EC quantification, NIOSH and IMPROVE_A show negative and positive EC bias, respectively – NIOSH exhibits premature EC evolution in the OC4 pure He phase, while IMPROVE_A OC4 temperature step (580 °C) is not sufficiently high, causing some OC to be carried over to He/O2 phase to be measured mainly as EC2. EUSAAR_2 minimizes both effects and may be most accurate in this aspect. However, IMPROVE_A is the only method that is capable of properly resolving individual OC and Philippines’s particularly abundant EC fractions owing to the protocol’s variable step durations. Concurrently, IMPROVE_A and EUSAAR_2 yield lowest pyrolized carbon (PC) formation for urban and rural site, respectively. Minimal PC formation is desired to minimize errors associated with its correction. Finally, transmittance laser correction is preferred over reflectance as it is capable of accounting for char formed within filter. The study thus recommends a modified IMPROVE_A, with increased OC4 temperature step (650 °C, adopted from EUSAAR_2) and transmittance laser correction, as optimal. This protocol is expected to give proper OC and EC evolution, fractionation, and measurement with minimized PC formation and proper correction, leading to more accurate results. Preliminary testing shows that recommended protocol meets those expectations. Application to larger number and wider variety of samples is needed to more properly assert these findings.
Mostrar más [+] Menos [-]Dynamite fishing in Tanzania Texto completo
2015
Slade, Lorna M. | Kalangahe, Baraka
Fishing using explosives is common in Tanzanian waters; it is considered to be more widely practised now than at any other point in history. Mwambao Coastal Community Network, a Tanzanian NGO carried out a multi-stakeholder consultation in April 2014 initiated through the concern of private investors and tourism operators. Consultations were held with villagers, fisheries officers, government officers, hoteliers, dive operators, fish processors, NGOs and other key individuals, and shed some light on key factors enabling this practice to flourish. Key areas identified for attention include engendering political will at all levels, upholding of the law through a non-corrupt enforcement and judicial system, and defining clear roles and responsibilities for monitoring and surveillance. The work identified other successful initiatives which have tackled this pervasive practice including projects that build local capacity for marine governance, villages that have declared themselves intolerant of blast-fishing, and private–public partnerships for patrol and protection.
Mostrar más [+] Menos [-]Pollution exposure on marine protected areas: A global assessment Texto completo
2015
Partelow, Stefan | von Wehrden, Henrik | Horn, Olga
Marine protected areas (MPAs) face many challenges in their aim to effectively conserve marine ecosystems. In this study we analyze the extent of pollution exposure on the global fleet of MPAs. This includes indicators for current and future pollution and the implications for regionally clustered groups of MPAs with similar biophysical characteristics. To cluster MPAs into characteristic signature groups, their bathymetry, baseline biodiversity, distance from shore, mean sea surface temperature and mean sea surface salinity were used. We assess the extent at which each signature group is facing exposure from multiple pollution types. MPA groups experience similar pollution exposure on a regional level. We highlight how the challenges that MPAs face can be addressed through governance at the appropriate scale and design considerations for integrated terrestrial and marine management approaches within regional level networks. Furthermore, we present diagnostic social-ecological indicators for addressing the challenges facing unsuccessful MPAs with practical applications.
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