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The influence of substrate material on ascidian larval settlement Full text
2016
Chase, Anna L. | Dijkstra, Jennifer A. | Harris, Larry G.
Submerged man-made structures present novel habitat for marine organisms and often host communities that differ from those on natural substrates. Although many factors are known to contribute to these differences, few studies have directly examined the influence of substrate material on organism settlement. We quantified larval substrate preferences of two species of ascidians, Ciona intestinalis (cryptogenic, formerly C. intestinalis type B) and Botrylloides violaceus (non-native), on commonly occurring natural (granite) and man-made (concrete, high-density polyethylene, PVC) marine materials in laboratory trials. Larvae exhibited species-specific settlement preferences, but generally settled more often than expected by chance on concrete and HDPE. Variation in settlement between materials may reflect preferences for rougher substrates, or may result from the influence of leached chemicals on ascidian settlement. These findings indicate that an experimental plate material can influence larval behavior and may help us understand how substrate features may contribute to differences in settlement in the field.
Show more [+] Less [-]Simulation of oil pollution in the Persian Gulf near Assaluyeh oil terminal Full text
2016
Faghihifard, M. | Badri, M.A.
Numerical simulation of oil slick movement with respect to tidal factors and wind effects was performed in order to counteract oil pollution in the Persian Gulf. First, a flow model was invoked with respect to water level fluctuations. The main tidal constituents were applied to the model using the initial conditions of water level variations in the Hormuz Strait near the Hangam Island. The movement of oil pollution was determined due to wind, tide and temperature effects and confirmed by applying a verified field results. Simulations were focused near an important terminal in the Persian Gulf, Assaluyeh Port. The results were led to preparing a risk-taking map in a parallel research for the Persian Gulf.
Show more [+] Less [-]Trace/heavy metal pollution monitoring in estuary and coastal area of Bay of Bengal, Bangladesh and implicated impacts Full text
2016
Kibria, Golam | Hossain, Md Maruf | Mallick, Debbrota | Lau, T.C. | Wu, R. S. S. (Rudolf Shiu-sun)
Using artificial mussels (AMs), this study reports and compares time-integrated level of eleven trace metals (Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, U, Zn) in Karnafuli River estuary and coastal area of the Bay of Bengal, Bangladesh.Through this study, “hot spots” of metal pollution were identified. The results may demonstrate that the Karnafuli Estuary, and adjacent coastal area of Chittagong, Bangladesh are highly polluted by high risk metals (cadmium, chromium, copper, mercury, nickel, lead, uranium). Agricultural, domestic and industrial wastes directly discharged into the waterways have been identified as the main causes of metal pollution in Chittagong, Bangladesh. The high level of metal pollution identified may impact on local water quality, and seafood catch, livelihoods of people and public health resulting from seafood consumption. There is a need for regular monitoring to ascertain that local water quality with respect to metal levels are within acceptable levels to safeguards both environmental health and public health.
Show more [+] Less [-]Dynamics of phytoplankton communities in eutrophying tropical shrimp ponds affected by vibriosis Full text
2016
Lemonnier, Hugues | Lantoine, François | Courties, Claude | Guillebault, Delphine | Nézan, Elizabeth | Chomérat, Nicolas | Escoubeyrou, Karine | Galinié, Christian | Blockmans, Bernard | Laugier, Thierry
Dynamics of phytoplankton communities in eutrophying tropical shrimp ponds affected by vibriosis Full text
2016
Lemonnier, Hugues | Lantoine, François | Courties, Claude | Guillebault, Delphine | Nézan, Elizabeth | Chomérat, Nicolas | Escoubeyrou, Karine | Galinié, Christian | Blockmans, Bernard | Laugier, Thierry
Tropical shrimp aquaculture systems in New Caledonia regularly face major crises resulting from outbreaks of Vibrio infections. Ponds are highly dynamic and challenging environments and display a wide range of trophic conditions. In farms affected by vibriosis, phytoplankton biomass and composition are highly variable. These conditions may promote the development of harmful algae increasing shrimp susceptibility to bacterial infections. Phytoplankton compartment before and during mortality outbreaks was monitored at a shrimp farm that has been regularly and highly impacted by these diseases. Combining information from flow cytometry, microscopy, pigment and phylogenetic analysis, the presence of Picocyanobacteria, Prasinophyceae and Diatomophyceae were detected as dominant phytoplankton groups and Cryptophyceae, Prymnesiophyceae and Dinophyceae as minor components. At the onset of the first shrimp mortalities, Bacillariophyceae increased while Cyanobacteria, Prymnesiophyceae and Dinophyceae decreased in the water column, followed by proliferation of Prasinophyceae. Several taxa were identified as potential harmful algae (Cyanobacteria, dinoflagellates and Phaeocystis).
Show more [+] Less [-]Dynamics of phytoplankton communities in eutrophying tropical shrimp ponds affected by vibriosis Full text
2016
Lemonnier, Hugues | Lantoine, Francois | Courties, Claude | Guillebault, Delphine | Nezan, Elisabeth | Chomerat, Nicolas | Escoubeyrou, Karine | Galinie, Christian | Blockmans, Bernard | Laugier, Thierry
Tropical shrimp aquaculture systems in New Caledonia regularly face major crises resulting from outbreaks of Vibrio infections. Ponds are highly dynamic and challenging environments and display a wide range of trophic conditions. In farms affected by vibriosis, phytoplankton biomass and composition are highly variable. These conditions may promote the development of harmful algae increasing shrimp susceptibility to bacterial infections. Phytoplankton compartment before and during mortality outbreaks was monitored at a shrimp farm that has been regularly and highly impacted by these diseases. Combining information from flow cytometry, microscopy, pigment and phylogenetic analysis, the presence of Picocyanobacteria, Prasinophyceae and Diatomophyceae were detected as dominant phytoplankton groups and Cryptophyceae, Prymnesiophyceae and Dinophyceae as minor components. At the onset of the first shrimp mortalities, Bacillariophyceae increased while Cyanobacteria, Prymnesiophyceae and Dinophyceae decreased in the water column, followed by proliferation of Prasinophyceae. Several taxa were identified as potential harmful algae (Cyanobacteria, dinoflagellates and Phaeocystis).
Show more [+] Less [-]Spatio-temporal distributions of chlorofluorocarbons and methyl iodide in the Changjiang (Yangtze River) estuary and its adjacent marine area Full text
2016
Yuan, Da | Yang, Gui-Peng | He, Zhen
Temporal and spatial distribution patterns of volatile halogenated organic compounds (VHOCs), such as dichlorodifluoromethane (CFC-12), trichlorofluoromethane (CFC-11), trichlorotrifluoroethane (CFC-113), and methyl iodide (CH3I), in the Changjiang (Yangtze River) estuary and its adjacent marine area were measured during two cruises from 21 February to 10 March 2014 and from 10 to 21 July 2014. VHOC concentrations showed seasonal variation with higher values during winter. VHOC distributions evidently decreased along the freshwater plume from the river mouth to the open sea and from inshore to offshore regions. VHOC distributions were obviously influenced by the Changjiang runoff, anthropogenic inputs, and biological release of phytoplankton. The study area was a net sink for CFC-12 and CFC-11, but a net source for atmospheric CH3I during the study periods.
Show more [+] Less [-]Measures for environmental conservation in enclosed coastal seas Full text
2016
Tomita, Akio | Nakura, Yoshio | Ishikawa, Takuya
With putting a focus on the balance among the nutrient salts such as nitrogen and phosphorus, the Ministry of the Environment (MOE) developed the Action Plan for Healthy Material Circulation in Ocean (just called the Healthy Plan). The plan aims to facilitate the healthy and smooth circulation of the nutrients with an integrated management over land and sea as a package in respective sea areas. The Healthy Plan is now in a pilot phase and is to be implemented for some selected model regions.Meanwhile, devastating tsunamis caused by the Great East Japan Earthquake on March 11th, 2011 severely damaged the natural environments in the affected regions. In the affected bays, seaweed beds and spawning grounds disappeared in a blink. MOE has launched on the recovery activities of Zostera (eelgrass) beds, using the concepts and the methods used in the “Sato-umi Creation” activity which is a purposeful environmental recovery project.
Show more [+] Less [-]Effect of cooking on total mercury content in Norway lobster and European hake and public health impact Full text
2016
Perugini, Monia | Zezza, Daniela | Tulini, Serena Maria Rita | Abete, Maria Cesarina | Monaco, Gabriella | Conte, Annamaria | Olivieri, Vincenzo | Amorena, Michele
The risk of Hg poisoning by eating seafood is considered real from the several international agencies that recommended, by fish consumption advisories, to pregnant women and young children to avoid or severely limit the consumption of the fish and shellfish with a high-range mercury levels. The analyses of two common species, European hake and Norway lobster, collected from an area of Central Adriatic Sea, reported high mercury levels in crustaceans. For Norway lobster total mercury exceeded, in six out of ten analysed pools, the recommended 0.5mg/kg wet weight European limit. Moreover the increased amount of Hg concentrations in Norway lobster cooked samples suggests the necessity to review current procedures of Hg control in food, considering also consumption habits of consumers. The Hg values found in all European hake samples are below the legal limits and, in this species, the boiling did not modify the concentrations in fish tissues.
Show more [+] Less [-]Effects of sedimentary sulfide on community structure, population dynamics, and colonization depth of macrozoobenthos in organic-rich estuarine sediments Full text
2016
Kanaya, Gen | Uehara, Tadayasu | Kikuchi, Eisuke
An annual field survey and in situ recolonization experiment revealed the effects of sedimentary sulfide (H2S) on macrozoobenthos in a eutrophic brackish lagoon. Species diversity was much lower throughout the year in muddy opportunist-dominant sulfidic areas. Mass mortality occurred during warmer months under elevated H2S levels. An enclosure experiment demonstrated that sedimentary H2S modified community composition, size structure, and colonization depth of macrozoobenthos. Species-specific responses to each sediment type (sand, sulfidic mud, and mud with H2S removed) resulted in changes in the established community structure. Dominant polychaetes (Hediste spp., Pseudopolydora spp., and Capitella teleta) occurred predominantly in a thin surface layer in the presence of H2S. On the other hand, organic-rich mud facilitated settlement of polychaete larvae if it does not contain H2S. These results demonstrate that sediment characteristics, including H2S level and organic content, were key structuring factors for the macrozoobenthic assemblage in organically polluted estuarine sediments.
Show more [+] Less [-]Risk assessment for marine spills along European coastlines Full text
2016
Fernández-Macho, Javier
A marine-spill risk index is proposed to measure and compare the relative vulnerability of coastal regions to marine spills in European waters. It is applied to 301 spills in European waters between 1970 and 2014 for 429 Eurostat territorial units and 156 regions in Europe's coasts. The results show a high heterogeneity among European coastal regions with areas, predominantly on the Atlantic coast, with high marine-spill risks. In particular, UK coasts are markedly affected as there are only five non-British coastal territories within the first 25 territorial units most at risk from marine spills. Across countries, European Atlantic countries face highest risks versus coastal countries on other European waters that are relatively safer. The index also shows a tendency of sea currents to have positive dispersal effects leading to smaller risks rather than otherwise. The index may help to design protection policies and reduce the vulnerability of sensitive resources.
Show more [+] Less [-]Environmental assessment of pesticides in the Mondego River Estuary (Portugal) Full text
2016
Cruzeiro, Catarina | Rocha, Eduardo | Pardal, Miguel Ângelo | Rocha, Maria João
The Mondego River estuary, located on the North Atlantic Ocean Ecoregion, is a basin affected by agricultural run-off with increasing signs of eutrophication. We evaluated the amounts and distribution of 56 priority pesticides belonging to distinct categories (insecticides, herbicides and fungicides). Temporal trends were considered and a total of 42 surface water samples were collected between 2010 and 2011. More than 55% of the GC–MS/MS-quantified pesticides were above the maximum amounts established by the European Directives (98/83/EC and 2013/39/EU). Based on the concentration addition (CA) and independent action (IA) models, we used a two-tiered approach to assess the hazard of the pesticide mixture, at the maximum concentration found, reflecting a potential risk. Short-term exposure using Artemia salina indicated a significant toxic effect where the locomotion of the animals was clearly affected.
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